Note: This is purely the output of the chat conversation and does not contain any raw data, codebase snippets, etc. used to generate the output.

User at 4:51 pm, Jun 29, 2024

I am still getting this error:

Access to XMLHttpRequest at 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' from origin 'http://localhost:5173' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

in my browser, even though I've added this to my CDK:

  const api = new apigateway.RestApi(this, 'HandTermApi', {
   restApiName: 'HandTerm Service',
   description: 'This service serves authentication requests.',
   // Add default CORS options here
   defaultCorsPreflightOptions: {
    allowOrigins: apigateway.Cors.ALL_ORIGINS, // Include both your production and local origins
    allowMethods: apigateway.Cors.ALL_METHODS,
    allowHeaders: ['Content-Type', 'X-Amz-Date', 'Authorization', 'X-Api-Key', 'X-Requested-With'],
   }
  });

Codeium at 4:51 pm, Jun 29, 2024

The CORS error you're experiencing indicates that the browser is blocking the request due to the server not including the appropriate CORS headers in the response. Your configuration in the CDK code seems intended to allow requests from any origin, which should work for development purposes like accessing your API from localhost.

Given the details you've provided, there are a few potential reasons why this might still be happening:

1. The CORS configuration might not have been deployed successfully. Ensure that the stack deployment was successful and that there were no errors during the process. You can redeploy your CDK stack to make sure the latest changes are applied. Use PowerShell to deploy:

   cdk deploy

2. Check if the CORS settings are correctly applied to the specific endpoint. If you've added methods to your API Gateway resources manually (e.g., using addMethod or integrating with a Lambda function), ensure that the CORS options are correctly set for those methods or resources. Sometimes, specific configurations might override or not correctly inherit the default configurations.

3. Ensure that the preflight request (OPTIONS method) is handled correctly. The browser sends an OPTIONS request as a preflight check to see if the CORS policy allows the actual request. API Gateway needs to respond correctly to this preflight request. While setting defaultCorsPreflightOptions should automatically handle this, it's good to confirm that the OPTIONS method is indeed present and configured for your endpoints.

4. Browser Caching: Sometimes, browsers cache CORS policies very aggressively. Try clearing your browser cache or testing the request in an incognito window to rule out caching issues.

5. Verify the actual response headers: You can use tools like Postman or curl to manually send a request to your endpoint and inspect the response headers. Look for Access-Control-Allow-Origin and other related CORS headers in the response to ensure they are present and correctly configured.

curl -i -X OPTIONS 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' -H 'Origin: http://localhost:5173' -H 'Access-Control-Request-Method: POST'

This command sends a preflight request similar to what your browser does. Check the response to ensure it contains the correct Access-Control-Allow-* headers.

If after these checks you're still facing issues, it might be helpful to review the specific method or resource configuration in your cdk/lib/cdk-stack.ts file related to the signUp endpoint to ensure it's correctly set up to inherit or apply the CORS configuration you've defined at the API level.

User at 5:01 pm, Jun 29, 2024

I did add the signUp function to the api like this:

Codeium at 5:02 pm, Jun 29, 2024

It looks like you've mentioned adding the signUp function to the API, but the specific details on how you've done so weren't provided in your message. However, I can guide you on ensuring that your signUp Lambda function is correctly integrated with your API Gateway and that CORS is properly configured for this endpoint.

Given your scenario and the existing CORS configuration on your API Gateway, you should ensure the following for your signUp function integration:

1. Lambda Function Integration: Make sure your signUp Lambda function is correctly integrated with an API Gateway resource. This typically involves creating a new resource under your API Gateway and then adding a method (e.g., POST) that uses a Lambda integration pointing to your signUp function.

2. CORS Configuration for the SignUp Endpoint: Even though you've set defaultCorsPreflightOptions at the API level, it's good to double-check if the specific resource/method tied to your signUp function correctly inherits or applies these settings.

Here's an example snippet on how to add a signUp function to your API Gateway, assuming you have a Lambda function named signUpLambda:

// Assuming api is your RestApi object and signUpLambda is your Lambda function for sign-up
const signUpResource = api.root.addResource('signUp');
const signUpIntegration = new apigateway.LambdaIntegration(signUpLambda);
signUpResource.addMethod('POST', signUpIntegration, {
  // Optional: Additional method options here
});

// Note: The defaultCorsPreflightOptions set at the API level should apply to this resource/method as well

3. Deploy Changes: After making changes to your CDK stack, ensure you deploy these changes to AWS. Using PowerShell:

   cdk deploy

4. Testing: After deployment, test your endpoint again. If CORS issues persist, use the curl command as shown previously to test the preflight OPTIONS request directly against your signUp endpoint.

If you've followed these steps or have a different setup for adding the signUp function to your API Gateway, please provide more details or clarify how the function is added so I can offer more targeted advice.

User at 5:05 pm, Jun 29, 2024

I added it like this, after setting the defaultCorsPreflightOptions

  const signUpLambda = new lambda.Function(this, 'SignUpFunction', {
   runtime: lambdaRuntime,
   handler: 'signUp.handler',
   role: lambdaExecutionRole,
   code: lambda.Code.fromAsset('lambda/authentication'),
   environment: {
    COGNITO_APP_CLIENT_ID: userPoolClient.userPoolClientId,
   }
  });


  const signUpIntegration = new apigateway.LambdaIntegration(signUpLambda);
  const signUpResource = api.root.addResource('signup');
  signUpResource.addMethod('POST', signUpIntegration);

Do I have to set CORS settings on that too, separately?

I believe I have deployed the cdk subsequently multiple times. How can I query the CORS settings from AWS CLI to confirm their status?

Codeium at 5:05 pm, Jun 29, 2024

Given your code snippet, it looks like you've correctly integrated the signUpLambda with the API Gateway and added it under a signup resource. Since you've already set defaultCorsPreflightOptions for the entire API, these CORS settings should apply to all routes, including your signup endpoint, as long as there's no specific override at the resource or method level that might alter the default behavior.

To confirm the CORS settings on your deployed API Gateway, you can use the AWS CLI to describe the REST API and check the CORS configuration. However, please note that the AWS CLI does not provide a direct way to query the CORS settings for an API Gateway. CORS is implemented as part of the OPTIONS method response headers for your resources.

You can still retrieve information about the deployed API Gateway resources and methods, which can help you infer the CORS setup. Here's how you can use the AWS CLI to check the configuration:

1. List Your APIs: First, find the ID of your API by listing all of your deployed APIs.

   aws apigateway get-rest-apis

2. Get Resources: Once you have your API ID, list all the resources in your API to find the resource ID for your signup endpoint. Replace API_ID with your actual API ID.

   aws apigateway get-resources --rest-api-id API_ID

3. Check the OPTIONS Method: Look for the resource corresponding to your signup endpoint. If CORS is configured, you should have an OPTIONS method associated with it. You can then describe this method to check its configuration, including headers. Replace RESOURCE_ID with the resource ID of your signup endpoint.

   aws apigateway get-method --rest-api-id API_ID --resource-id RESOURCE_ID --http-method OPTIONS

This command will show you the method response, including any headers set up for the OPTIONS method, which are crucial for CORS. Specifically, you would look for headers like Access-Control-Allow-Origin in the method response.

If after checking you find that the CORS settings do not seem to be applied or are incorrect, you might have to manually adjust the OPTIONS method for your signup resource or ensure that the defaultCorsPreflightOptions are correctly configured and deployed in your CDK stack.

Remember, after making any changes to your CDK code or AWS resources, you need to redeploy your stack for those changes to take effect:

cdk deploy

Also, always ensure your AWS CLI is configured with the correct permissions and targeting the right region to interact with your API Gateway.

User at 5:10 pm, Jun 29, 2024

I get this result:

 aws apigateway get-method --rest-api-id u4ceo7qshi --resource-id p1xomh011j --http-method OPTIONS
- apiKeyRequired: false
 authorizationType: NONE
 httpMethod: OPTIONS
 methodIntegration:
  cacheKeyParameters: []
  cacheNamespace: p1xomh011j
  integrationResponses:
   '204':
    responseParameters:
     method.response.header.Access-Control-Allow-Headers: '''Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Requested-With'''
     method.response.header.Access-Control-Allow-Methods: '''OPTIONS,GET,PUT,POST,DELETE,PATCH,HEAD'''
     method.response.header.Access-Control-Allow-Origin: '''*'''
    statusCode: '204'
  passthroughBehavior: WHEN_NO_MATCH
  requestTemplates:
   application/json: '{ statusCode: 200 }'
  timeoutInMillis: 29000
  type: MOCK
 methodResponses:
  '204':
   responseParameters:
    method.response.header.Access-Control-Allow-Headers: true
    method.response.header.Access-Control-Allow-Methods: true
    method.response.header.Access-Control-Allow-Origin: true
   statusCode: '204'

Codeium at 5:10 pm, Jun 29, 2024

The output you've shared indicates that the OPTIONS method for your signup endpoint has been configured correctly to support CORS. The Access-Control-Allow-* headers are properly set to allow requests from any origin (*), to accept the specified headers (Content-Type, X-Amz-Date, Authorization, X-Api-Key, X-Requested-With), and to permit various HTTP methods (OPTIONS, GET, PUT, POST, DELETE, PATCH, HEAD). The status code 204 indicates a successful response with no content, which is typical for OPTIONS preflight responses.

Given this configuration, your API should not be causing the CORS issue as described. If you're still encountering CORS errors in your browser, consider the following additional troubleshooting steps:

1. Cache: Ensure that you're not experiencing a caching issue with your browser. Try accessing the API from an incognito window or after clearing your browser's cache.

2. Request Headers: Verify that the request headers sent by your application match those allowed by the Access-Control-Allow-Headers in your API configuration. Discrepancies here could cause the browser to reject the preflight response.

3. Client Code: Double-check the client-side code making the request to ensure it's correctly formed and not adding unexpected headers or setting credentials without proper configuration on the server side.

4. Deployment: Confirm that there are no deployment issues and that the latest version of your API configuration is active. Sometimes, changes might not be fully propagated, or an older version of the API could be cached at some layer in the AWS infrastructure.

5. Test with a Tool: Use tools like Postman or CURL to directly test the OPTIONS request and another request type (e.g., POST) to your signup endpoint. This can help you verify that the server-side setup is correct independently of any browser-specific behaviors.

If the CORS error persists despite these checks, you may want to review any recent changes to your client-side application that could impact how requests are made. Sometimes, the issue might not be with the API Gateway or Lambda setup but rather with how the browser is handling or sending requests based on changes in the client-side code or environment.

User at 5:19 pm, Jun 29, 2024

To answer your question about headers, I copy the first request (the app makes two) as a cUrl request it says this:

curl 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' \
 -H 'sec-ch-ua: "Not/A)Brand";v="8", "Chromium";v="126", "Microsoft Edge";v="126"' \
 -H 'Accept: application/json, text/plain, */*' \
 -H 'Content-Type: application/json' \
 -H 'Referer: http://localhost:5173/' \
 -H 'sec-ch-ua-mobile: ?0' \
 -H 'User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0' \
 -H 'sec-ch-ua-platform: "Windows"' \
 --data-raw '{"username":"[email protected]"}'

Codeium at 5:19 pm, Jun 29, 2024

The cURL request you've shared is helpful for understanding the issue. The request headers include several sec-ch-ua-* headers, which are part of a newer set of headers introduced to offer a more granular control and insight over the User-Agent string. These headers are sent by modern browsers as part of the Client Hints API.

The CORS error might be happening because the Access-Control-Allow-Headers in your API Gateway CORS configuration does not explicitly list these sec-ch-ua-* headers. While the configuration you checked includes common headers such as Content-Type, Authorization, etc., missing headers specifically required by your client application (like the sec-ch-ua-* headers in this case) can lead to CORS preflight checks failing.

To resolve this issue, you should update the CORS configuration for your API Gateway to explicitly allow these sec-ch-ua-* headers. You will need to add the headers to the Access-Control-Allow-Headers configuration in your API. Based on the provided cURL request, you should add at least the following:

• sec-ch-ua
• sec-ch-ua-mobile
• sec-ch-ua-platform

And any other headers you expect to send as part of requests to your API.

Here's how you can update your default CORS configuration in CDK to include these headers:

const api = new apigateway.RestApi(this, 'HandTermApi', {
  restApiName: 'HandTerm Service',
  description: 'This service serves authentication requests.',
  defaultCorsPreflightOptions: {
    allowOrigins: apigateway.Cors.ALL_ORIGINS,
    allowMethods: apigateway.Cors.ALL_METHODS,
    allowHeaders: [
      'Content-Type',
      'X-Amz-Date',
      'Authorization',
      'X-Api-Key',
      'X-Requested-With',
      'sec-ch-ua',
      'sec-ch-ua-mobile',
      'sec-ch-ua-platform'
    ],
  }
});

After updating your CDK script with the additional headers, redeploy your stack:

cdk deploy

This should update the CORS policy on your API Gateway to explicitly allow the sec-ch-ua-* headers, thereby resolving the CORS error for your requests. Remember to test your endpoint again after the deployment completes to confirm that the issue is resolved.

User at 5:30 pm, Jun 29, 2024

I am still getting the same error, but I am also noticing something in the Browser Dev Tools:

Request URL:
https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUpReferrer Policy:
strict-origin-when-cross-origin

That is under the Headers tab, under the General section, so I don't know exactly where it is getting that from.

The call is made from the useAuth:

 const signUp = async (username: string, password: string, email: string) => {
  try {
   await axios.post(`${API_URL}/signUp`, { username, password, email });
   // Handle post-signup logic (e.g., auto-login or redirect to login page)
  } catch (error) {
   console.error('Signup failed:', error);
   throw error;
  }
 };

I don't know if anything needs to be done with headers there.

Codeium at 5:31 pm, Jun 29, 2024

The Referrer Policy: strict-origin-when-cross-origin you're seeing in the browser's Dev Tools under the Headers tab is a security feature controlling how much referrer information should be included with requests. In this context, it's unlikely the source of your CORS issue, as the referrer policy primarily affects how browsers handle the Referer (not a typo) header when making requests.

However, since you're still encountering CORS issues after adjusting your API Gateway's CORS settings to include the sec-ch-ua-* headers, it's worth examining the client-side request further. Given that the request is made from your useAuth hook with axios, you generally don't need to manually set CORS headers from the client side; those are response headers set by the server (your API Gateway, in this case) to tell the client (the browser) which origins, methods, and headers are permitted.

One thing to check is whether your API's endpoint URL is precisely matched in your request. You've used ${API_URL}/signUp, but the error mentions signUpReferrer. If that's not a typo in copying the error message, it might indicate an issue with how the URL is constructed or encoded in your request. Ensure there are no unintended concatenations or typographical errors in how you assemble your endpoint URL.

If the URL is correct and you've confirmed the API Gateway is configured correctly for CORS, consider these additional steps:

1. Double-Check the Endpoint URL: Make absolutely sure the URL in your axios call matches the deployed API Gateway endpoint. It should end in /signup (note the lowercase 'u'), matching the resource name you defined in your CDK script.

2. Verify Axios Version: Ensure you're using a recent version of axios, as older versions might behave unexpectedly. You can check your version in your package.json file and update if necessary.

3. Inspect Network Traffic: Use your browser's network inspector to examine the failed request closely. Check the Request URL and Request Headers sections for any discrepancies, such as unexpected characters or paths in the URL.

4. Hardcode the URL: Temporarily replace ${API_URL} in your axios call with the full URL string you're trying to access (e.g., 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup'). This can help rule out issues related to environment variables or string interpolation.

5. Manual Test with Postman or Curl: If you haven't already, manually test the endpoint using Postman or curl with a simple request. This can help isolate whether the problem lies with the API configuration or the way the frontend application is making the request.

6. Review API Deployment: Ensure your API Gateway deployment is up to date with the latest changes. Sometimes changes to resources or methods require redeploying the API in the AWS Console or via CLI/CDK commands.

Here's an example of a curl command you could use to test, replacing with your actual endpoint and data:

curl -X POST 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' \
-H 'Content-Type: application/json' \
-d '{"username": "example", "password": "example", "email": "[email protected]"}'

If none of these steps resolve the issue, please provide any additional error messages or behaviors you observe, which could offer further clues.

User at 5:36 pm, Jun 29, 2024

I can run this from bash:

$ curl -X POST 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' -H 'Content-Type: application/json' -d '{"username": "[email protected]", "password": "Pass_w0rd", "email": "[email protected]"}'
{"UserConfirmed":false,"CodeDeliveryDetails":{"Destination":"e***@e***","DeliveryMedium":"EMAIL","AttributeName":"email"},"UserSub":"d4488408-20f1-70ce-806d-433e7baa0df2"}

And, I have been executing this from the useAuth.http the whole time:

### Sign Up
POST {{ $dotenv VITE_API_URL}}/signup HTTP/1.1
content-type: application/json

{
"username": "[email protected]",
"email": "[email protected]",
"password": "FastTrack#1"
}

HTTP/1.1 400 Bad Request
Content-Type: application/json
Content-Length: 21
Connection: close
Date: Sun, 30 Jun 2024 00:35:40 GMT
x-amzn-RequestId: ec86ffca-09a0-4076-ae69-2c75e7187e0d
x-amz-apigw-id: aJ8-YHpsIAMEppg=
X-Amzn-Trace-Id: Root=1-6680a85b-590a817717366edd07a1f962;Parent=49064df17175067e;Sampled=0;lineage=b7b1ca60:0
X-Cache: Error from cloudfront
Via: 1.1 c5ce554a66cf9007b8e39d06afcf462c.cloudfront.net (CloudFront)
X-Amz-Cf-Pop: LAX3-C4
X-Amz-Cf-Id: mJDDL_TT09ZUR43knQ6W1gj7sNYN7zJCIvZN3EV681ItDmrhfJ3k0Q==

"User already exists"

Maybe that means I need to close my browser and restart it.

Codeium at 5:36 pm, Jun 29, 2024

The successful execution of your curl command directly in the terminal, which interacts with your AWS API Gateway endpoint and returns a valid response, indicates that your server-side setup (including CORS configuration, Lambda function, and integration with the API Gateway) is correctly configured and operational for the /signup endpoint.

The error message "User already exists" from executing the request in useAuth.http confirms that your API is receiving and processing requests as expected, but the user you're trying to create already exists in your user pool, which is an expected response for trying to sign up with an already registered email.

Given this information, if you're still experiencing CORS errors solely when making requests from your browser, restarting the browser could indeed resolve the issue if it's related to caching or stale session data. Browsers can sometimes cache preflight CORS responses, leading to inconsistent behaviors, especially after changes to the server's CORS configuration.

Here are a few additional steps to try:

1. Restart the Browser: Completely close and reopen your browser, then try the request again.

2. Use Incognito Mode: Open an incognito or private browsing window and attempt the request again. This can help rule out issues caused by caching or browser extensions.

3. Clear Browser Cache: Clear your browser's cache and cookies for the site you're testing. This ensures that your browser is not using outdated CORS information.

4. Check for Browser Extensions: Sometimes, browser extensions can interfere with HTTP requests. Try disabling any extensions that could affect web requests, especially those related to security, privacy, or CORS.

5. Review Browser Console and Network Logs: Open the Developer Tools in your browser, and carefully review the console and network tabs for any additional error messages or warnings that might provide more clues.

6. Cross-Origin Isolation: If your application uses features that require cross-origin isolation (e.g., SharedArrayBuffer), ensure that your server sends the appropriate headers (Cross-Origin-Opener-Policy and Cross-Origin-Embedder-Policy). This is more advanced and typically not the cause of basic CORS issues but worth mentioning for completeness.

If after restarting the browser and clearing caches the problem persists, it's important to systematically review any differences between how the request is being made from your browser application versus the direct curl command or requests made from useAuth.http. The issue might stem from how the request is constructed in your application code or a specific browser policy affecting the request.

User at 6:01 pm, Jun 29, 2024

Incognito is a great idea, but it still doesn't work.

Exact same results, as far as I can tell.

Request URL:
https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUpReferrer Policy:
strict-origin-when-cross-origin

Accept:
application/json, text/plain, */*
Content-Type:
application/json
Referer:
http://localhost:5173/
Sec-Ch-Ua:
"Not/A)Brand";v="8", "Chromium";v="126", "Microsoft Edge";v="126"
Sec-Ch-Ua-Mobile:
?0
Sec-Ch-Ua-Platform:
"Windows"
User-Agent:
Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0

Is there any way for axios to export it's request before sending it?

 const signUp = async (username: string, password: string, email: string) => {
  try {
   await axios.post(`${API_URL}/signUp`, { username, password, email });
   // Handle post-signup logic (e.g., auto-login or redirect to login page)
  } catch (error) {
   console.error('Signup failed:', error);
   throw error;
  }
 };

Codeium at 6:02 pm, Jun 29, 2024

If you're encountering persistent CORS issues despite the server-side configuration appearing correct, and you wish to examine the exact request axios is making before it's sent, you can use axios interceptors. Interceptors allow you to run your code or modify the request and response before the request is sent or before the promise is fulfilled.

Here’s how you can add a request interceptor to log the request details:

import axios from 'axios';

// Add a request interceptor
axios.interceptors.request.use(function (config) {
    // Log the entire request configuration
    console.log(config);
    // You could also log specific parts, e.g., URL and headers
    console.log(`Request URL: ${config.url}`);
    console.log(`Request Headers:`, config.headers);
    console.log(`Request Method: ${config.method}`);
    console.log(`Request Data:`, config.data);
    // Important: return the config or the request will be stopped here!
    return config;
}, function (error) {
    // Do something with request error
    return Promise.reject(error);
});

// Your signUp function remains the same
const signUp = async (username: string, password: string, email: string) => {
    try {
        await axios.post(`${API_URL}/signUp`, { username, password, email });
        // Handle post-signup logic (e.g., auto-login or redirect to login page)
    } catch (error) {
        console.error('Signup failed:', error);
        throw error;
    }
};

This interceptor will log the request details to the console right before sending it, which can be incredibly useful for debugging. You can see exactly what URL, headers, and data are being sent in the request. This can help you verify that the request is formed correctly and might help identify the issue.

Remember, interceptors will affect every request made with axios from the point they are defined, so if you have other axios requests in your application, they will also be logged or modified by the interceptor. If you need the interceptor to apply only to specific requests, consider creating an axios instance with .create() and applying interceptors to that instance instead of the global axios object.

After examining the request details, if everything seems to be correctly set up from the client-side and you're still facing CORS issues, you might want to revisit the server-side configuration or ensure that the deployed API Gateway settings match what you expect.

User at 6:11 pm, Jun 29, 2024

I like the interceptor, but it didn't show me any headers that I didn't already see.

I have found something else, though. There is a second request in the browser Network tab. The first one has Type=xhr. The second one has Type=preflight, and it has a bunch of other info in the Headers tab:

Remote Address:
13.225.142.81:443Referrer Policy:
strict-origin-when-cross-origin
Response Headers
Request Headers
Console
Animations
Developer resources
Issues
Performance monitor
Crash analyzer

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localhost/:1  
Access to XMLHttpRequest at 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' from origin 'http://localhost:5173' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.

Codeium at 6:11 pm, Jun 29, 2024

The presence of a second request in the browser's Network tab with Type=preflight is a key piece of information. This preflight request is an automatic check performed by browsers for requests that do not meet the CORS "simple requests" criteria. It uses the HTTP OPTIONS method to query the server for its CORS policy, specifically looking for the Access-Control-Allow-Origin header among others. This preflight occurs before the actual request (Type=xhr) is made.

The error message you're seeing indicates that the preflight request did not receive the Access-Control-Allow-Origin header in its response, which is necessary for the browser to proceed with the actual request. This is consistent with the CORS issue you've been experiencing.

Given this new information, here are a few things to consider:

1. Check Server Response to Preflight Request: Despite the initial configuration appearing correct, the server's response to the preflight OPTIONS request is missing the necessary CORS headers. You might want to manually test the OPTIONS request to your endpoint using a tool like Postman or curl to see exactly what headers are being returned. For example:

   curl -X OPTIONS 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' \
   -H 'Access-Control-Request-Method: POST' \
   -H 'Origin: http://localhost:5173' \
   -i

   This command simulates the preflight request and includes -i to show response headers. The response should include Access-Control-Allow-Origin and other CORS headers.

2. Ensure API Gateway Deployment: Even with the correct configuration, changes might not take effect until the API Gateway deployment is updated. Make sure that any changes to CORS settings or the API configuration have been deployed. You can do this through the AWS Management Console or by re-deploying your CDK stack.

3. Review API Gateway CORS Configuration: Double-check that the CORS configuration on your API Gateway specifically allows requests from http://localhost:5173, or uses * (less secure) to allow requests from any origin. Ensure that OPTIONS requests are allowed and correctly return the necessary CORS headers.

4. API Gateway Integration Response: Ensure that your API Gateway's integration response for the OPTIONS method explicitly includes the necessary CORS headers. Sometimes, despite configuring CORS at the API level, the OPTIONS method needs to be manually configured to return these headers.

5. Custom Domain Names and Base Path Mappings: If you are using custom domain names and base path mappings in API Gateway, ensure these are correctly configured. Incorrect configurations here can lead to routing issues that might affect CORS behavior.

The preflight request's failure to pass the CORS check suggests that the issue lies with how the API Gateway is responding to this OPTIONS request. Start by manually verifying the response to the preflight request and ensuring your API Gateway deployment reflects your CORS configuration accurately.

User at 6:20 pm, Jun 29, 2024

When I run that curl I get this response:

curl -X OPTIONS 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' \
-H 'Access-Control-Request-Method: POST' \
-H 'Origin: http://localhost:5173' \
-i
HTTP/2 403 
content-type: application/json
content-length: 42
date: Sun, 30 Jun 2024 01:12:57 GMT
x-amzn-requestid: a3abb66c-8eae-4dc0-9145-3ddcdd29ad79
x-amzn-errortype: MissingAuthenticationTokenException
x-amz-apigw-id: aKCb-HNhoAMEaIA=
x-cache: Error from cloudfront
via: 1.1 211d2bc0b23405deaf02a4b025d65090.cloudfront.net (CloudFront)
x-amz-cf-pop: LAX3-C4
x-amz-cf-id: 23t3g0nHdVHGvSe3K07zawgEv7MCng1xIM_JoLWKH8lS-UlhEeTQSg==

{"message":"Missing Authentication Token"}

I'm not exactly sure how the authentication token is handled now that we're using HttpOnly Cookies. In fact, I'm not sure if the Lambda tokenHandler that sets HttpOnly Cookies is being triggeres in the ApiGatway HTTP round-trip that you and I set up in the cdk-stack.ts over these last couple of days.

Could the CORS problem actually be a token error that's not handled properly? Or, I guess that would show up in the other curl calls and the useAuth.http request/response. But those worked.

Codeium at 6:20 pm, Jun 29, 2024

The 403 Missing Authentication Token error you're receiving from the curl command when trying to perform an OPTIONS request is a bit misleading and common with AWS API Gateway. Despite the error message, this usually does not relate to the kind of authentication tokens you might be thinking of (like JWTs or session tokens), especially for a preflight OPTIONS request, which should not require authentication.

In the context of AWS API Gateway, the "Missing Authentication Token" error can often mean that the request URL is not matched by any resource or method in your API Gateway setup. This could be due to a misconfiguration or a typo in the resource path. However, since your other POST requests to the same URL (/signup) are succeeding, it's less likely about a simple typo and more about how the OPTIONS requests are handled.

Here are a few considerations and steps to resolve this issue:

• CORS Configuration: Ensure that your API Gateway's CORS configuration for the /signup resource explicitly allows OPTIONS requests and includes the necessary CORS headers in responses to such requests. This setup should be handled automatically by specifying defaultCorsPreflightOptions in your CDK script, but it's worth reviewing to ensure it's applied correctly.

• Manual OPTIONS Method: If the automatic CORS configuration isn't working as expected, you might need to manually set up an OPTIONS method for your /signup resource that returns the necessary CORS headers. This can be done through the AWS Management Console or programmatically via CDK or the AWS CLI.

1. Review API Gateway Configuration: Double-check your API Gateway resource and method configurations in the AWS Management Console. Ensure that the /signup resource exists and that the OPTIONS method is present and configured correctly.

2. Redeploy API Gateway: Changes to API Gateway resources and configurations require redeploying your API for the changes to take effect. Make sure that you've redeployed your API after making any CORS-related changes.

3. CDK Deployment: Ensure that your CDK stack is successfully deployed and reflects the latest changes you've made. Sometimes, deployment issues can cause the deployed resources not to match your expectations.

4. Directly Configure OPTIONS Method: If automatic CORS isn't applying as expected, consider manually adding an OPTIONS method to your signup resource in the CDK script or directly through the AWS Management Console. This method should return a response with the necessary Access-Control-Allow-* headers without requiring authentication.

5. Inspect CloudFront Distribution: If you're using CloudFront in front of API Gateway, ensure there's no caching behavior interfering with the OPTIONS requests. Sometimes, CloudFront can cache responses in a way that impacts dynamic content delivery or CORS behavior.

The CORS problem you're facing is likely not directly related to an actual token error but rather the setup of your API Gateway to correctly respond to preflight OPTIONS requests. The fact that POST requests are working suggests that the authentication and token handling mechanism is functioning correctly for those requests, and the issue is specific to how OPTIONS requests are handled or configured.

User at 6:30 pm, Jun 29, 2024

I think each of those checks should be expressed as an aws cli command that I can run in the command line and record the results of.

Codeium at 6:30 pm, Jun 29, 2024

Certainly, using the AWS CLI to check your setup can provide a clear understanding of your API Gateway configuration and help identify any discrepancies. Below are the AWS CLI commands that correspond to the troubleshooting steps mentioned:

To get the list of all your API Gateways, which helps to identify the API ID for further inspection:

aws apigateway get-rest-apis

After identifying your API ID (e.g., u4ceo7qshi), list the resources to see if the /signup resource exists and to get its resource ID:

aws apigateway get-resources --rest-api-id u4ceo7qshi

Once you have the resource ID for /signup (e.g., p1xomh011j), check the configuration of the OPTIONS method to ensure it's set up correctly:

aws apigateway get-method --rest-api-id u4ceo7qshi --resource-id p1xomh011j --http-method OPTIONS

If you have made changes to the API Gateway configuration, ensure to redeploy. You first need the deployment ID, which you can find by listing the deployments of your API:

aws apigateway get-deployments --rest-api-id u4ceo7qshi

Then, redeploy to the appropriate stage (e.g., prod) by creating a new deployment:

aws apigateway create-deployment --rest-api-id u4ceo7qshi --stage-name prod

If you need to manually configure the OPTIONS method for CORS, you would first ensure the method exists. If it doesn't, you'd typically use the console for manual setup due to the complexity of setting response headers through CLI. However, updating existing OPTIONS method response can be done via:

aws apigateway update-method-response --rest-api-id u4ceo7qshi --resource-id p1xomh011j --http-method OPTIONS --status-code 200 --patch-operations op=replace,path=/responseParameters/method.response.header.Access-Control-Allow-Origin,value="'*'"

And similarly for other required headers. Note: This command is more illustrative; actual operations might vary based on your specific CORS requirements.

• Ensure your AWS CLI is configured with the correct permissions to execute these commands.
• Replace placeholders (e.g., u4ceo7qshi, p1xomh011j) with actual values from your API Gateway setup.
• For complex configurations, especially those involving modifying response headers or creating new methods, the AWS Management Console may offer a more user-friendly interface.

These steps should help you verify your API Gateway's configuration regarding CORS and ensure that your setup is correctly applied and deployed.

User at 7:04 pm, Jun 29, 2024

I am unclear on deployment.

I was under the impression that cdk deploy would deploy the items in the CDK, but I have seen the Deploy button in the Api Gateway web UI.

When I run this:

aws apigateway get-deployments --rest-api-id u4ceo7qshi
- items:
 - createdDate: '2024-06-29T18:57:07-07:00'
  description: This service serves authentication requests.
  id: vgajg1

I get that response. I meant to ask you about this but wanted to handle the other issues first. Also, I think I should create a UAT as well as a Prod, but that is secondary.

Codeium at 7:05 pm, Jun 29, 2024

Your understanding that cdk deploy should deploy all resources defined in your CDK stack, including setting up the API Gateway and its deployment, is correct. The CDK abstracts away many of the manual steps you would otherwise have to perform via the AWS Management Console or AWS CLI, including creating deployments. When you use cdk deploy, it does indeed create a deployment for your API Gateway as part of the process, based on the state of your resources as defined in your CDK stack.

The output of aws apigateway get-deployments --rest-api-id u4ceo7qshi shows that a deployment has been created for your API Gateway. Each deployment is essentially a snapshot of your API's resources and methods at the time of deployment. The id: vgajg1 is the identifier for this deployment.

The Deploy button you see in the API Gateway web UI is used for creating new deployments manually or updating existing stages with a newer deployment. This can be useful for quick updates or when you're managing your API Gateway resources directly via the Console rather than through infrastructure as code tools like the AWS CDK.

When you manage your infrastructure through the CDK, it's generally best practice to keep all changes and deployments within the CDK to maintain consistency and ensure that your infrastructure is defined as code. Manually deploying through the API Gateway UI can lead to discrepancies between your live infrastructure and your CDK definitions.

Creating multiple environments like UAT (User Acceptance Testing) and Prod (Production) is a common requirement. With the CDK, you can handle this by defining separate stacks or using conditional logic within a single stack to create resources specific to each environment. You might use different stack names or pass environment-specific context parameters when you run cdk deploy.

For example, you could deploy a UAT version of your stack using:

cdk deploy MyStack --context environment=uat

And then deploy your production stack with:

cdk deploy MyStack --context environment=prod

In your CDK code, you would check the context and adjust resource properties accordingly. This allows you to maintain separate configurations and deployments for different environments within the same CDK project.

• CDK Deploy: Continues to manage your infrastructure and deployments through CDK commands to ensure consistency.
• API Gateway Deployments: Use the AWS CLI or Console for manual inspections or emergency updates, but aim to keep infrastructure changes within your CDK codebase.
• Multiple Environments: Leverage the CDK's capabilities to manage different environments, such as UAT and Prod, within the same codebase by using context parameters or separate stacks.

User at 7:36 pm, Jun 29, 2024

Since I am the only person using the application at this point, I will continue using the Prod environment as the UAT for now, until I have another user, at which point I will create a UAT. I dont' know if I will be able to diferentiate the environment in the GitHub Pages infrastructure, but I don't have to worry about that until some time after I get this CORS problem fixed.

Speaking of which, I think we are no closer to solving that, right?

We found that the AWS infrastructure is deployed to handle CORS, but we are still getting a CORS error in the browser.

Or did I miss something when we were talking about the preflight HTTP request?

Codeium at 7:36 pm, Jun 29, 2024

It's a practical approach to use your Prod environment as UAT while you're the only user, especially for early stages of development. When the time comes to differentiate environments, especially with front-end deployments like GitHub Pages, you can explore strategies like using different branches or repositories to represent different environments, or dynamic environment configuration in your front-end code based on the URL or a build variable.

Regarding the CORS issue, it indeed seems we're still facing the challenge despite verifying the AWS infrastructure is set up to handle CORS. The crux of the problem appears to be related to the preflight HTTP request not being correctly acknowledged by your API Gateway setup, as indicated by the 403 Missing Authentication Token error you encountered when testing with curl. This error is misleading since preflight requests typically don't require authentication tokens, suggesting a misconfiguration or misunderstanding in how the API Gateway handles or responds to preflight requests.

Given this, let's recap and consider the next steps specifically related to troubleshooting and resolving the CORS issue:

• Successful cURL Test: Direct POST requests to your API endpoint work fine via cURL, indicating that the lambda function and API Gateway are generally configured correctly for handling requests.
• Failed Preflight Request in Browsers: The browser's preflight OPTIONS request fails with a CORS error, indicating that the browser does not receive the expected CORS headers (Access-Control-Allow-Origin, etc.) in response to this preflight request.

1. Double-Check the OPTIONS Method Setup: Re-confirm that your API Gateway has an OPTIONS method for your /signup endpoint that correctly returns the required CORS headers without requiring authentication. Manual configuration might be necessary if the automated CORS configuration via CDK didn't apply as expected.

2. Inspect API Gateway Logs: Enable detailed CloudWatch logging for your API Gateway to capture the exact request and response details for preflight requests. This can provide insights into what's happening when the preflight request is processed.

   • To enable logging, you can follow the AWS documentation or adjust your CDK code to include logging configuration for your API Gateway.

3. Hardcode CORS Headers: As a temporary measure to isolate the problem, consider manually adding CORS headers to the response of your lambda function or directly through the API Gateway method response for the OPTIONS method. This is more of a workaround but can help determine if the issue is solely with the CORS header configuration.

4. Review CloudFront Distribution (If Applicable): If you are using CloudFront in front of API Gateway, ensure that CloudFront is not stripping out necessary headers or otherwise interfering with the CORS process.

5. Manually Invoke OPTIONS Method: Use curl or another tool to manually invoke the OPTIONS method on your endpoint, closely inspecting the request and response headers to ensure the necessary CORS headers are present.

curl -X OPTIONS 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' \
-H 'Origin: http://localhost:5173' \
-H 'Access-Control-Request-Method: POST' \
-i

6. Simplify CORS Configuration: If your CORS configuration is complex, consider simplifying it temporarily to the most basic setup (e.g., allowing all origins and methods) to see if the issue persists. This can help identify if the problem lies in the specifics of the configuration.

CORS issues can be particularly tricky to diagnose because they involve both server configuration and client-side enforcement by browsers. The key is to methodically isolate where the breakdown occurs, typically by ensuring that the server's responses to preflight requests contain all the necessary headers to satisfy the browser's CORS policy enforcement.

User at 7:55 pm, Jun 29, 2024

These are the OPTIONS I get from the AWS CLI:

aws apigateway get-method --rest-api-id u4ceo7qshi --resource-id p1xomh011j --http-method OPTIONS
- apiKeyRequired: false
 authorizationType: NONE
 httpMethod: OPTIONS
 methodIntegration:
  cacheKeyParameters: []
  cacheNamespace: p1xomh011j
  integrationResponses:
   '204':
    responseParameters:
     method.response.header.Access-Control-Allow-Headers: '''Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Requested-With,sec-ch-ua,sec-ch-ua-mobile,sec-ch-ua-platform'''
     method.response.header.Access-Control-Allow-Methods: '''OPTIONS,GET,PUT,POST,DELETE,PATCH,HEAD'''
     method.response.header.Access-Control-Allow-Origin: '''*'''
    statusCode: '204'
  passthroughBehavior: WHEN_NO_MATCH
  requestTemplates:
   application/json: '{ statusCode: 200 }'
  timeoutInMillis: 29000
  type: MOCK
 methodResponses:
  '204':
   responseParameters:
    method.response.header.Access-Control-Allow-Headers: true
    method.response.header.Access-Control-Allow-Methods: true
    method.response.header.Access-Control-Allow-Origin: true
   statusCode: '204'

And this is what I get from the curl request:

curl -X OPTIONS 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' \
-H 'Origin: http://localhost:5173' \
-H 'Access-Control-Request-Method: POST' \
-i
HTTP/2 204 
date: Sun, 30 Jun 2024 02:38:42 GMT
x-amzn-requestid: 8771b129-e92b-4e6c-8e06-ce500e60a4ae
access-control-allow-origin: *
access-control-allow-headers: Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Requested-With,sec-ch-ua,sec-ch-ua-mobile,sec-ch-ua-platform
x-amz-apigw-id: aKO_4EFWoAMEtGw=
access-control-allow-methods: OPTIONS,GET,PUT,POST,DELETE,PATCH,HEAD
x-cache: Miss from cloudfront
via: 1.1 bced04c07f9fc5f2c1cc29deb7204ba8.cloudfront.net (CloudFront)
x-amz-cf-pop: LAX3-C4
x-amz-cf-id: Pz83sZYey7_tG7gask1nR7P1Hy1d58RntLe8_QFfGR6t56tbZs33wg==

Should I add this to the axios request?

Codeium at 7:55 pm, Jun 29, 2024

The information you've provided shows that your API Gateway OPTIONS method for the /signup endpoint is correctly configured to support CORS, and the successful curl request to the OPTIONS method is returning the appropriate CORS headers. This indicates that the server-side setup is likely correct, and the CORS preflight check should pass as long as the client-side request is conforming to the expectations set by these CORS headers.

Given that your axios request from the browser still encounters CORS errors despite the server seemingly configured correctly, adding the CORS headers to the axios request directly is not necessary or recommended. CORS response headers, such as Access-Control-Allow-Origin, are meant to be sent by the server in response to the browser's preflight request. The browser then uses these headers to determine if the actual request is allowed. The client (your React application using axios) does not need to (and should not) set these response headers on the request.

Here's why your Axios request does not need modification to include CORS headers:

• Browser Responsibility: Handling CORS is the browser's responsibility. The browser automatically sends the Origin header and expects the server to respond with Access-Control-Allow-Origin and other CORS-related headers if needed.
• Server Configuration: Your API must include the correct CORS headers in its responses. Since your curl test shows that your API does return the correct CORS headers for the OPTIONS request, the server-side seems to be configured properly.
• Client-Side Headers: The client-side code (using axios) should focus on sending the correct Content-Type, authentication (if applicable), and other request-specific headers. CORS headers are not set by client-side code.

Since the server-side appears to be configured correctly but you're still experiencing issues, here are a couple of avenues to explore:

1. Review the Actual Request: Double-check the actual request being made by your application. Ensure it matches the expectations (HTTP method, headers, etc.) that your API Gateway's CORS configuration allows. This includes verifying that the URL is correct and that no unexpected headers are being added by the client.

2. Inspect Browser Behavior: Use the browser's developer tools to inspect the failed network request. Look closely at the request headers and review the response headers of the preflight OPTIONS request to ensure they match what you saw with the curl test.

3. Consider Proxy Configuration: If you're using a development server (like Webpack Dev Server used with Create React App) or a proxy in front of your API, ensure it's correctly configured to forward requests to the API Gateway without modifying them in ways that could cause CORS issues.

4. Test in Different Environments: Sometimes, behavior can differ between local development environments and production. If feasible, test your application in a deployed environment (closer to your API's deployment environment) to see if the issue persists.

5. Review API Gateway Deployment: Ensure that the deployment of your API Gateway reflects the latest configuration changes. Even though the curl test indicates that the OPTIONS method responds correctly, it's essential to ensure that all changes are fully deployed and propagated.

6. Hard Refresh / Clear Cache: As a simple but sometimes overlooked step, ensure you've done a hard refresh or cleared your browser cache to rule out caching issues.

Since the direct axios modification to include response CORS headers is not the correct approach, focusing on these areas should help you further diagnose and potentially resolve the issue.

User at 8:11 pm, Jun 29, 2024

I don't think I understand the preflight request. That seems to be related to the problem and a big difference than how we make the request with curl.

I am trying your suggestion #2, to compare what the browser is doing to the curl calls, but I don't know how to do that with the preflight request.

Codeium at 8:11 pm, Jun 29, 2024

Understanding the preflight request and how it differs from a direct curl call is crucial in diagnosing CORS issues.

A preflight request is an automatic request sent by web browsers to verify the CORS policy of a server before sending the actual request. Preflight requests use the OPTIONS HTTP method and include headers such as Origin, Access-Control-Request-Method, and Access-Control-Request-Headers that describe the actual (forthcoming) request to be made. The server must respond with appropriate CORS headers (Access-Control-Allow-Origin, Access-Control-Allow-Methods, Access-Control-Allow-Headers, etc.) to indicate that the actual request is allowed from the origin.

• Automatic: Browsers automatically initiate preflight requests. In contrast, curl commands must be manually crafted and executed by the developer. A curl command to an endpoint directly attempts the actual request without the preliminary CORS check that a browser preflight performs.
• Conditional: Not every request from a browser triggers a preflight. "Simple requests" (e.g., a GET or POST with certain safe headers) might not require preflight checks. However, requests that involve custom headers, PUT, DELETE, or other conditions will trigger a preflight.
• Transparent to Developers: Developers do not code preflight requests into their applications. Instead, these are handled by the browser based on the nature of the request being made.

When comparing what the browser does to curl calls, focus on the following:

1. Request Method and Headers: Look at the actual request method (GET, POST, PUT, etc.) and headers being sent by your application (viewable in the browser's developer tools, under the Network tab). Compare these to the headers and method used in your curl call. Ensure they match up, especially content-type and any custom headers.

2. Preflight Response: In the browser's developer tools, under the Network tab, you can find the preflight OPTIONS request and inspect its response headers. These should include Access-Control-Allow-Origin, Access-Control-Allow-Methods, and Access-Control-Allow-Headers that match or allow the actual request your application is making.

3. Actual Request and Response: After the preflight, inspect the actual request in the browser's developer tools. Ensure it's being sent as expected and compare any server response or error with what you receive via curl.

1. Open Developer Tools: Right-click on your webpage and select "Inspect" or "Inspect Element", then navigate to the "Network" tab.
2. Trigger the Request: Perform the action in your application that triggers the network request.
3. Find the Preflight Request: Look for an OPTIONS request preceding the actual API call. It will have the same endpoint/path as your actual request.
4. Inspect Headers: Click on the OPTIONS request to inspect. Look for:
   • Request Headers: These are what the browser is asking permission to use in the actual request.
   • Response Headers: These should match or allow the headers and method from the actual request. Specifically, check Access-Control-Allow-Origin, Access-Control-Allow-Methods, and Access-Control-Allow-Headers.

Understanding the differences in how your application's requests are treated by the browser versus direct curl testing is key to diagnosing and resolving CORS issues. Remember, the goal is to ensure that your server's response to the preflight request explicitly permits the actual request your client-side application makes.

User at 8:32 pm, Jun 29, 2024

The browser Dev Tools provide a feature to output requests in various other formats.

Here is the one that it gives me for the preflight request, and the response when I run it:

curl 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' `
∙  -X 'OPTIONS' `
∙  -H 'accept: */*' `
∙  -H 'accept-language: en-US,en;q=0.9' `
∙  -H 'access-control-request-headers: access-control-allow-origin,content-type' `
∙  -H 'access-control-request-method: POST' `
∙  -H 'origin: http://localhost:5173' `
∙  -H 'priority: u=1, i' `
∙  -H 'referer: http://localhost:5173/' `
∙  -H 'sec-fetch-dest: empty' `
∙  -H 'sec-fetch-mode: cors' `
∙  -H 'sec-fetch-site: cross-site' `
∙  -H 'user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0'
{"message":"Missing Authentication Token"}

Then, if I run the subsequent request I get:

 curl 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' `
∙  -H 'sec-ch-ua: "Not/A)Brand";v="8", "Chromium";v="126", "Microsoft Edge";v="126"' `
∙  -H 'sec-ch-ua-mobile: ?0' `
∙  -H 'User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0' `
∙  -H 'Content-Type: application/json' `
∙  -H 'Access-Control-Allow-Origin: *' `
∙  -H 'Accept: application/json, text/plain, */*' `
∙  -H 'Referer: http://localhost:5173/' `
∙  -H 'sec-ch-ua-platform: "Windows"' `
∙  --data-raw '{"username":"[email protected]","password":"Pass_w0rd","email":"[email protected]"}'
{"message":"Missing Authentication Token"}

Codeium at 8:33 pm, Jun 29, 2024

The "Missing Authentication Token" error you're encountering when trying to replicate the browser's preflight request using curl is indicative of an issue with how the API Gateway is being accessed, but the context here is slightly different.

1. Preflight Request Error: For the preflight OPTIONS request, the "Missing Authentication Token" error is misleading. AWS API Gateway returns this error when a request is made to a resource or method that doesn't exist. Since preflight requests don't require authentication tokens (they're CORS mechanisms), this error usually means the API Gateway is not configured to respond to OPTIONS requests for the given route, despite what might seem to be correct configuration. However, since your earlier test with curl showed a successful OPTIONS response, this specific replication attempt might not accurately reflect the request made by the browser or there's a configuration discrepancy.

2. Actual Request Error: For the actual POST request, including the Access-Control-Allow-Origin header in the request from curl is incorrect. This header is a response header, not a request header. The browser expects this header in responses from the server to allow the request under the CORS policy. Your curl command should not include this header when making requests, as it doesn't have any effect on the server-side and might confuse the situation.

Given this information and focusing specifically on resolving the CORS issue, consider the following steps:

• Review API Gateway Configuration: Double-check that your API Gateway is configured to handle OPTIONS requests for the /signup route. This might involve ensuring that a MOCK integration or the correct method responses are set up to return the necessary CORS headers without requiring authentication.

• Ensure Correct Deployment: Make sure that any changes to the API Gateway configuration, especially those related to CORS settings or OPTIONS method responses, are deployed. You may need to create a new deployment or redeploy your current stage after making changes.

• Simplify curl Commands for Testing:

  • For preflight testing, simplify your curl command to focus on the essential headers:

    curl -X OPTIONS 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' `
    -H 'Origin: http://localhost:5173' `
    -H 'Access-Control-Request-Method: POST' `
    -i

  • For actual request testing, remove the Access-Control-Allow-Origin header and any other response-specific headers:

    curl -X POST 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signUp' `
    -H 'Content-Type: application/json' `
    -d '{"username":"[email protected]","password":"Pass_w0rd","email":"[email protected]"}'

• Consult API Gateway Logs: If you haven't already, enable detailed CloudWatch Logging for your API Gateway to get more insights into the requests and the responses being sent out by the API Gateway. This can provide more detailed error messages or clues as to what might be misconfigured.

By focusing on these areas, you should be able to further diagnose and hopefully resolve the CORS issue, ensuring that your preflight and actual requests are correctly handled by the API Gateway.

User at 9:08 pm, Jun 29, 2024

We already checked that I deployed and what the options are several times.

I am comparing and contrasting the curl calls now.

I think the "Missing authenticatoin token" was happening because the useAuth.ts used signUp while the actual url uses signup. I fixed that and now I don't get that error.

Now, I can copy the curl that the browser Dev Tools gives me and run it in PowerShell and it works without error:

 curl 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' `
∙ -H 'accept: application/json, text/plain, */*' `
∙ -H 'accept-language: en-US,en;q=0.9' `
∙ -H 'content-type: application/json' `
∙ -H 'origin: http://localhost:5173' `
∙ -H 'priority: u=1, i' `
∙ -H 'referer: http://localhost:5173/' `
∙ -H 'sec-ch-ua: "Not/A)Brand";v="8", "Chromium";v="126", "Microsoft Edge";v="126"' `
∙ -H 'sec-ch-ua-mobile: ?0' `
∙ -H 'sec-ch-ua-platform: "Windows"' `
∙ -H 'sec-fetch-dest: empty' `
∙ -H 'sec-fetch-mode: cors' `
∙ -H 'sec-fetch-site: cross-site' `
∙ -H 'user-agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0' `    
∙ --data-raw '{"username":"[email protected]","password":"Pass_w0rd","email":"[email protected]"}'
"User already exists"

Codeium at 9:08 pm, Jun 29, 2024

It's good to hear that you've identified and fixed the issue with the URL mismatch (signUp vs. signup). Case sensitivity in URLs is a common source of errors, especially when transitioning between environments (local development vs. deployed services) or between different parts of your application (frontend vs. backend). This kind of mistake can lead to seemingly perplexing behaviors, such as the "Missing Authentication Token" error, which is more about the API Gateway not finding a matched resource than about actual authentication tokens.

• URL Correction: Correcting the URL in your useAuth.ts to match the case sensitivity of the actual endpoint (signup instead of signUp) resolved the "Missing Authentication Token" error. This suggests that the API Gateway resource was correctly set up for /signup but not for /signUp, resulting in the API Gateway not recognizing the incorrect URL and thus throwing an error commonly associated with unconfigured paths or methods.
• Successful curl Test: Being able to run the curl command successfully in PowerShell and getting a meaningful application-specific response ("User already exists") indicates that your backend is correctly receiving and processing requests when they are correctly addressed.

• Frontend to Backend Consistency: This resolution underscores the importance of ensuring consistency between your frontend and backend in terms of endpoint URLs. It's a good practice to define these URLs in a shared or easily referenced location within your codebase to prevent similar issues.
• Testing with the Frontend: Now that the direct curl test works, the next step is to re-test the signup functionality from your frontend application. Since the URL mismatch was the root cause of the problem you were experiencing, fixing it should ideally resolve the CORS error you were seeing in the browser as well.
• Review Error Handling: This might also be a good time to review error handling in your frontend application to ensure that errors like a "Missing Authentication Token" (which was misleading in this context) or a 404 not found due to incorrect URL paths are clearly communicated to you during development or debugging sessions.
• Consider URL Validation or Standardization: Implementing a form of URL validation or standardization in the part of your codebase that constructs API requests can help catch similar issues early. Middleware or helper functions that enforce lowercase paths, for example, could prevent similar issues from arising in the future.

The successful curl test confirms that your backend is set up correctly to handle requests to the /signup endpoint. The main takeaway is the importance of attention to detail with URLs in API requests, a common yet easily overlooked aspect of web development.

User at 9:14 pm, Jun 29, 2024

I guess I left out the part that I'm still experiencing the CORS error in the browser.

I like everything you said about url validation and standardization. I want that.

But first I have to figure out how the two-step browser fetch is breaking what the browser-exported curl call can do. I'm going to export the call in a couple more formats, just to check.

Is there a way to mimic more drectly the prefetch/fetch process that the browser is doing?

Codeium at 9:14 pm, Jun 29, 2024

The challenge you're facing with CORS errors in the browser, despite successful curl tests, highlights the differences between how browsers and command-line tools like curl handle requests, especially with regard to CORS. Browsers enforce CORS policies by making preflight requests, which do not happen in curl or similar tools unless manually replicated.

To more closely mimic the browser's preflight and actual request process, you can use tools or scripts that emulate both the preflight OPTIONS request and the subsequent POST (or other method) request. Here’s how you can manually replicate this two-step process using curl:

First, simulate the preflight request by sending an OPTIONS request with the necessary CORS headers:

curl -X OPTIONS 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' `
-H 'Origin: http://localhost:5173' `
-H 'Access-Control-Request-Method: POST' `
-H 'Access-Control-Request-Headers: content-type' `
-i

This request includes:

• Origin: Indicates the requesting origin.
• Access-Control-Request-Method: The method that will be used in the actual request.
• Access-Control-Request-Headers: Any headers that will be included in the actual request.

After the preflight, simulate the actual request (assuming the preflight indicates that the request is allowed):

curl -X POST 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' `
-H 'Content-Type: application/json' `
-H 'Origin: http://localhost:5173' `
--data-raw '{"username":"[email protected]","password":"Pass_w0rd","email":"[email protected]"}'

This attempts to closely replicate what the browser does: an OPTIONS request followed by the actual POST request, both including the Origin header.

• Server Response to Preflight: The key is how your server responds to the preflight OPTIONS request. The server must include Access-Control-Allow-Origin (matching the request's Origin), Access-Control-Allow-Methods, and Access-Control-Allow-Headers (matching or allowing the headers in the actual request) in its response for the browser to proceed with the actual request.
• Matching Browser Requests: Ensure that the headers and methods you use in your manual curl tests match those being used by your frontend application as closely as possible. Differences here can lead to discrepancies in behavior.
• Automated Testing Tools: For more complex scenarios or continuous testing, consider using automated testing tools or scripts that can replicate these steps and validate the responses. Tools like Postman can be configured to simulate preflight requests but require manual setup for each test scenario.

By manually replicating the preflight and actual request process, you can gain insights into how your server responds to each step and diagnose where the breakdown in CORS policy adherence occurs. This approach helps isolate issues by closely emulating the browser's behavior, providing clues to resolve the CORS error.

User at 9:18 pm, Jun 29, 2024

Both of those curl calls work. :-(

I remembered that the browser Dev Tools also let me export a HAR, which I think has more info:

{
 "log": {
  "version": "1.2",
  "creator": {
   "name": "WebInspector",
   "version": "537.36"
  },
  "pages": [
   {
    "startedDateTime": "2024-06-30T03:57:06.469Z",
    "id": "page_7",
    "title": "http://localhost:5173/",
    "pageTimings": {
     "onContentLoad": 135.64000000769738,
     "onLoad": 144.38800000061747
    }
   }
  ],
  "entries": [
   {
    "_initiator": {
     "type": "script",
     "stack": {
      "callFrames": [
       {
        "functionName": "dispatchXhrRequest",
        "scriptId": "665",
        "url": "http://localhost:5173/node_modules/.vite/deps/axios.js?v=a9349980",
        "lineNumber": 1634,
        "columnNumber": 12
       },
       {
        "functionName": "xhr",
        "scriptId": "665",
        "url": "http://localhost:5173/node_modules/.vite/deps/axios.js?v=a9349980",
        "lineNumber": 1517,
        "columnNumber": 9
       },
       {
        "functionName": "dispatchRequest",
        "scriptId": "665",
        "url": "http://localhost:5173/node_modules/.vite/deps/axios.js?v=a9349980",
        "lineNumber": 1956,
        "columnNumber": 9
       }
      ],
      "parent": {
       "description": "Promise.then",
       "callFrames": [
        {
         "functionName": "_request",
         "scriptId": "665",
         "url": "http://localhost:5173/node_modules/.vite/deps/axios.js?v=a9349980",
         "lineNumber": 2143,
         "columnNumber": 26
        },
        {
         "functionName": "request",
         "scriptId": "665",
         "url": "http://localhost:5173/node_modules/.vite/deps/axios.js?v=a9349980",
         "lineNumber": 2062,
         "columnNumber": 24
        },
        {
         "functionName": "httpMethod",
         "scriptId": "665",
         "url": "http://localhost:5173/node_modules/.vite/deps/axios.js?v=a9349980",
         "lineNumber": 2190,
         "columnNumber": 18
        },
        {
         "functionName": "wrap",
         "scriptId": "665",
         "url": "http://localhost:5173/node_modules/.vite/deps/axios.js?v=a9349980",
         "lineNumber": 7,
         "columnNumber": 14
        },
        {
         "functionName": "signUp",
         "scriptId": "657",
         "url": "http://localhost:5173/src/lib/useAuth.ts?t=1719719326861",
         "lineNumber": 33,
         "columnNumber": 18
        },
        {
         "functionName": "handleCommand",
         "scriptId": "654",
         "url": "http://localhost:5173/src/components/HandTerm.tsx?t=1719709052282",
         "lineNumber": 203,
         "columnNumber": 22
        },
        {
         "functionName": "handleCharacter",
         "scriptId": "654",
         "url": "http://localhost:5173/src/components/HandTerm.tsx?t=1719709052282",
         "lineNumber": 326,
         "columnNumber": 11
        },
        {
         "functionName": "onDataHandler",
         "scriptId": "663",
         "url": "http://localhost:5173/src/components/XtermAdapter.tsx",
         "lineNumber": 128,
         "columnNumber": 15
        },
        {
         "functionName": "fire",
         "scriptId": "676",
         "url": "http://localhost:5173/node_modules/.vite/deps/@xterm_xterm.js?v=a9349980",
         "lineNumber": 2637,
         "columnNumber": 58
        },
        {
         "functionName": "",
         "scriptId": "676",
         "url": "http://localhost:5173/node_modules/.vite/deps/@xterm_xterm.js?v=a9349980",
         "lineNumber": 2646,
         "columnNumber": 31
        },
        {
         "functionName": "fire",
         "scriptId": "676",
         "url": "http://localhost:5173/node_modules/.vite/deps/@xterm_xterm.js?v=a9349980",
         "lineNumber": 2637,
         "columnNumber": 58
        },
        {
         "functionName": "triggerDataEvent",
         "scriptId": "676",
         "url": "http://localhost:5173/node_modules/.vite/deps/@xterm_xterm.js?v=a9349980",
         "lineNumber": 5520,
         "columnNumber": 277
        },
        {
         "functionName": "_keyDown",
         "scriptId": "676",
         "url": "http://localhost:5173/node_modules/.vite/deps/@xterm_xterm.js?v=a9349980",
         "lineNumber": 690,
         "columnNumber": 521
        },
        {
         "functionName": "",
         "scriptId": "676",
         "url": "http://localhost:5173/node_modules/.vite/deps/@xterm_xterm.js?v=a9349980",
         "lineNumber": 531,
         "columnNumber": 200
        }
       ]
      }
     }
    },
    "_priority": "High",
    "_resourceType": "xhr",
    "cache": {},
    "pageref": "page_7",
    "request": {
     "method": "POST",
     "url": "https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup",
     "httpVersion": "",
     "headers": [
      {
       "name": ":authority",
       "value": "u4ceo7qshi.execute-api.us-east-1.amazonaws.com"
      },
      {
       "name": ":method",
       "value": "POST"
      },
      {
       "name": ":path",
       "value": "/prod/signup"
      },
      {
       "name": ":scheme",
       "value": "https"
      },
      {
       "name": "accept",
       "value": "application/json, text/plain, */*"
      },
      {
       "name": "accept-encoding",
       "value": "gzip, deflate, br, zstd"
      },
      {
       "name": "accept-language",
       "value": "en-US,en;q=0.9"
      },
      {
       "name": "content-length",
       "value": "79"
      },
      {
       "name": "content-type",
       "value": "application/json"
      },
      {
       "name": "origin",
       "value": "http://localhost:5173"
      },
      {
       "name": "priority",
       "value": "u=1, i"
      },
      {
       "name": "referer",
       "value": "http://localhost:5173/"
      },
      {
       "name": "sec-ch-ua",
       "value": "\"Not/A)Brand\";v=\"8\", \"Chromium\";v=\"126\", \"Microsoft Edge\";v=\"126\""
      },
      {
       "name": "sec-ch-ua-mobile",
       "value": "?0"
      },
      {
       "name": "sec-ch-ua-platform",
       "value": "\"Windows\""
      },
      {
       "name": "sec-fetch-dest",
       "value": "empty"
      },
      {
       "name": "sec-fetch-mode",
       "value": "cors"
      },
      {
       "name": "sec-fetch-site",
       "value": "cross-site"
      },
      {
       "name": "user-agent",
       "value": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0"
      }
     ],
     "queryString": [],
     "cookies": [],
     "headersSize": -1,
     "bodySize": 79,
     "postData": {
      "mimeType": "application/json",
      "text": "{\"username\":\"[email protected]\",\"password\":\"Pass_w0rd\",\"email\":\"[email protected]\"}"
     }
    },
    "response": {
     "status": 400,
     "statusText": "Bad Request",
     "httpVersion": "",
     "headers": [
      {
       "name": "content-length",
       "value": "21"
      },
      {
       "name": "content-type",
       "value": "application/json"
      },
      {
       "name": "date",
       "value": "Sun, 30 Jun 2024 04:14:57 GMT"
      },
      {
       "name": "via",
       "value": "1.1 4a2d0108313826df520a9cce037691c4.cloudfront.net (CloudFront)"
      },
      {
       "name": "x-amz-apigw-id",
       "value": "aKdGAEyDoAMEkMg="
      },
      {
       "name": "x-amz-cf-id",
       "value": "8qqhG1ZpBajRh01-DOAarCC_IUFnp1DZuu81O1IEOF71X2iNkAqIzw=="
      },
      {
       "name": "x-amz-cf-pop",
       "value": "LAX3-C4"
      },
      {
       "name": "x-amzn-requestid",
       "value": "20035e03-61b4-4c22-a40b-e928857bd4fd"
      },
      {
       "name": "x-amzn-trace-id",
       "value": "Root=1-6680dbbf-688aec4b6d9b0013403e3e24;Parent=5c9e2e343cffb07a;Sampled=0;lineage=b7b1ca60:0"
      },
      {
       "name": "x-cache",
       "value": "Error from cloudfront"
      }
     ],
     "cookies": [],
     "content": {
      "size": 0,
      "mimeType": "x-unknown"
     },
     "redirectURL": "",
     "headersSize": -1,
     "bodySize": -1,
     "_transferSize": 0,
     "_error": "net::ERR_FAILED"
    },
    "serverIPAddress": "",
    "startedDateTime": "2024-06-30T04:14:55.736Z",
    "time": 2166.5800000046147,
    "timings": {
     "blocked": 2166.5800000046147,
     "dns": -1,
     "ssl": -1,
     "connect": -1,
     "send": 0,
     "wait": 0,
     "receive": 0,
     "_blocked_queueing": 304.50299999210984
    }
   },
   {
    "_initiator": {
     "type": "preflight",
     "url": "https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup",
     "requestId": "31440.755"
    },
    "_priority": "High",
    "_resourceType": "preflight",
    "cache": {},
    "connection": "29766",
    "pageref": "page_7",
    "request": {
     "method": "OPTIONS",
     "url": "https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup",
     "httpVersion": "http/2.0",
     "headers": [
      {
       "name": ":authority",
       "value": "u4ceo7qshi.execute-api.us-east-1.amazonaws.com"
      },
      {
       "name": ":method",
       "value": "OPTIONS"
      },
      {
       "name": ":path",
       "value": "/prod/signup"
      },
      {
       "name": ":scheme",
       "value": "https"
      },
      {
       "name": "accept",
       "value": "*/*"
      },
      {
       "name": "accept-encoding",
       "value": "gzip, deflate, br, zstd"
      },
      {
       "name": "accept-language",
       "value": "en-US,en;q=0.9"
      },
      {
       "name": "access-control-request-headers",
       "value": "content-type"
      },
      {
       "name": "access-control-request-method",
       "value": "POST"
      },
      {
       "name": "origin",
       "value": "http://localhost:5173"
      },
      {
       "name": "priority",
       "value": "u=1, i"
      },
      {
       "name": "referer",
       "value": "http://localhost:5173/"
      },
      {
       "name": "sec-fetch-dest",
       "value": "empty"
      },
      {
       "name": "sec-fetch-mode",
       "value": "cors"
      },
      {
       "name": "sec-fetch-site",
       "value": "cross-site"
      },
      {
       "name": "user-agent",
       "value": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/126.0.0.0 Safari/537.36 Edg/126.0.0.0"
      }
     ],
     "queryString": [],
     "cookies": [],
     "headersSize": -1,
     "bodySize": 0
    },
    "response": {
     "status": 204,
     "statusText": "No Content",
     "httpVersion": "http/2.0",
     "headers": [
      {
       "name": "access-control-allow-headers",
       "value": "Content-Type,X-Amz-Date,Authorization,X-Api-Key,X-Requested-With,sec-ch-ua,sec-ch-ua-mobile,sec-ch-ua-platform"
      },
      {
       "name": "access-control-allow-methods",
       "value": "OPTIONS,GET,PUT,POST,DELETE,PATCH,HEAD"
      },
      {
       "name": "access-control-allow-origin",
       "value": "*"
      },
      {
       "name": "date",
       "value": "Sun, 30 Jun 2024 04:14:55 GMT"
      },
      {
       "name": "via",
       "value": "1.1 4a2d0108313826df520a9cce037691c4.cloudfront.net (CloudFront)"
      },
      {
       "name": "x-amz-apigw-id",
       "value": "aKdF-FUjIAMEHFw="
      },
      {
       "name": "x-amz-cf-id",
       "value": "NADrjL_NiFBtenqG5bGpZfm5E7FFhiBRLBayfFcV9bgiUFkdIjiyhw=="
      },
      {
       "name": "x-amz-cf-pop",
       "value": "LAX3-C4"
      },
      {
       "name": "x-amzn-requestid",
       "value": "70270ce2-4fb5-49ba-bb82-dc1f5879d188"
      },
      {
       "name": "x-cache",
       "value": "Miss from cloudfront"
      }
     ],
     "cookies": [],
     "content": {
      "size": 0,
      "mimeType": "x-unknown"
     },
     "redirectURL": "",
     "headersSize": -1,
     "bodySize": -1,
     "_transferSize": 0,
     "_error": null
    },
    "serverIPAddress": "13.225.142.59",
    "startedDateTime": "2024-06-30T04:14:55.738Z",
    "time": 302.23800000109156,
    "timings": {
     "blocked": 44.876,
     "dns": 0.04100000000000392,
     "ssl": 23.68,
     "connect": 39.187000000000005,
     "send": 0.48099999999999454,
     "wait": 217.07000000017604,
     "receive": 0.5830000009154901,
     "_blocked_queueing": -1
    }
   }
  ]
 }
}

Codeium at 9:18 pm, Jun 29, 2024

The HAR (HTTP Archive) file you provided gives a detailed view of the network transactions between your browser and the server, specifically for the preflight OPTIONS request and the actual POST request to the /signup endpoint. Analyzing this information can help us better understand why the browser fetch process might be failing due to CORS, despite the curl commands working as expected.

1. Preflight Request: The preflight OPTIONS request succeeded, indicated by a 204 No Content response, which is typical for preflight requests. The response headers from the preflight request include the necessary CORS headers (Access-Control-Allow-Origin: *, Access-Control-Allow-Methods, and Access-Control-Allow-Headers), suggesting that the server is correctly configured to respond to CORS preflight requests from http://localhost:5173.

2. Actual Request: The actual POST request to /signup includes request headers typical of a browser-based CORS request, such as Origin, Content-Type, and various Sec-Fetch-* headers. The server responded with a 400 Bad Request, which is an application-level error response. This indicates that the request was received by the server but was rejected due to issues with the request content or parameters, not CORS.

• CORS Configuration Appears Correct: Your AWS API Gateway and backend seem correctly configured to handle CORS, given the successful preflight response. The issue does not appear to be with CORS configuration but with the actual request handling or validation on the server.

• Focus on Server-Side Validation: The 400 Bad Request response suggests the need to focus on the server-side validation or handling of the /signup request. Ensure that the request body ({"username":"[email protected]","password":"Pass_w0rd","email":"[email protected]"}) meets all the server's expectations in terms of format, content, and any other validation rules in place.

• Check API Gateway and Lambda Logs: If your backend is AWS Lambda or another serverless service, check the logs for the specific invocation corresponding to your request. These logs may provide more detailed error messages or exceptions thrown by your code.

• Error Handling in Frontend: Ensure your frontend correctly handles and displays error responses from the server. This can help debug issues by providing immediate feedback on what might be wrong with the request.

• Testing with Other Tools: Although not necessary for CORS debugging (since your preflight is clearly succeeding), tools like Postman or Insomnia can offer a more GUI-driven way to test API requests and can sometimes provide a different perspective on what might be going wrong.

Given the information from the HAR file, the immediate action should not be focused on CORS but rather on understanding the specifics behind the 400 Bad Request response from the server. This involves reviewing server-side logic, validation, and potentially the structure of the request payload.

User at 9:24 pm, Jun 29, 2024

Ok, wait, I just tried it from the browser with a new email address and I got an email from Cognito to sign up.

So you are right, the error we are getting now is an internal app unhandled error, not a CORS error, even though the browser console tells me:

Access to XMLHttpRequest at 'https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com/prod/signup' from origin 'http://localhost:5173' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource.

Maybe the internal error is just preventing a CORS-ok header in the response or something.

Codeium at 9:24 pm, Jun 29, 2024

The discrepancy you're observing, where the browser reports a CORS error but the operation (like a sign-up process) actually succeeds, is an interesting scenario. This can happen when an API call triggers a process successfully (e.g., creating a new user in Cognito and sending a sign-up email), but the server fails to handle the response properly, particularly in terms of CORS headers.

1. CORS Is a Browser-Level Security Feature: Remember that CORS (Cross-Origin Resource Sharing) errors are enforced by the browser. The server's response must include the appropriate CORS headers (Access-Control-Allow-Origin, Access-Control-Allow-Methods, etc.) for the browser to accept the response and make it available to the JavaScript code that initiated the request.

2. Server-Side Error Handling: If your server encounters an error after the main operation has succeeded (like processing the sign-up but failing on something afterward), and if that error disrupts the normal response process (including setting CORS headers), the browser will report a CORS error. This is because the browser expects specific CORS headers on all responses, but if an error prevents those headers from being added, the browser interprets it as a CORS issue.

3. Successful Operation but Failed Response: The operation (user sign-up) can succeed if it's processed before any internal error occurs. This would explain why the sign-up email is sent. However, if an error occurs before the response is finalized (and before CORS headers are set), the browser will report a CORS error due to the absence of the Access-Control-Allow-Origin header in the error response.

• Check Server-Side Logs: Investigate logs on your server or backend service for any errors occurring during or after processing the sign-up requests. Look for exceptions or error messages that occur after the main operation but before the response is sent.

• Review Error Handling Code: Ensure your backend explicitly sets CORS headers even when returning error responses. This can sometimes be overlooked in error handling logic.

• Middleware or Framework Configuration: If you're using a web framework or middleware to handle CORS, ensure it's correctly configured to add CORS headers to all responses, including error responses. Some frameworks may require explicit configuration to ensure CORS headers are present on error responses.

• Test with Various Scenarios: Try testing with different request scenarios (such as different payloads or query parameters) to see if the issue persists across all types of requests or only specific ones. This can help isolate the problem.

By focusing on these areas, you should be able to identify and resolve the issue causing the misleading CORS error message in the browser. Ensuring that your server reliably adds CORS headers to every response, including error responses, is key to resolving this issue.

User at 9:29 pm, Jun 29, 2024

The server code is this:

// cdk/lambda/authentication/signUp.ts

const AWS = require('aws-sdk');
const cognito = new AWS.CognitoIdentityServiceProvider({region: 'us-east-1'});

exports.handler = async (event: { body: string; }) => {
 console.log("signUp function called");
 console.log('Received event:', event); // Log the incoming event

 try {
  const {username, password, email} = JSON.parse(event.body);
  console.log(`Processing signUp for username: ${username}, email: ${email}`); // Log the extracted variables

  var params = {
   ClientId: process.env.COGNITO_APP_CLIENT_ID,
   Username: username,
   Password: password,
   UserAttributes: [
    {
     Name: 'email',
     Value: email
    },
   ],
  };

  const data = await cognito.signUp(params).promise();
  console.log('SignUp success:', JSON.stringify(data)); // Log successful signup
  return { statusCode: 200, body: JSON.stringify(data) };
 } catch (err: any) {
  console.error('SignUp error:', err); // Log any errors that occur
  return { statusCode: 400, body: JSON.stringify(err.message) };
 }
};

Codeium at 9:29 pm, Jun 29, 2024

Based on the server code you've shared for the signUp function, it appears that the function is designed to process signup requests by interacting with AWS Cognito. However, the response object does not explicitly include any CORS headers. This omission is likely the cause of the CORS errors you're encountering in the browser, especially if an error response is sent back without these crucial headers.

To resolve the CORS issue and ensure that your Lambda function responds correctly to browser-based requests, you'll need to modify the response object to include the necessary CORS headers. Here's how you can modify your server code to include these headers:

// cdk/lambda/authentication/signUp.ts

const AWS = require('aws-sdk');
const cognito = new AWS.CognitoIdentityServiceProvider({region: 'us-east-1'});

exports.handler = async (event: { body: string; }) => {
 console.log("signUp function called");
 console.log('Received event:', event); // Log the incoming event

 try {
  const {username, password, email} = JSON.parse(event.body);
  console.log(`Processing signUp for username: ${username}, email: ${email}`); // Log the extracted variables

  var params = {
   ClientId: process.env.COGNITO_APP_CLIENT_ID,
   Username: username,
   Password: password,
   UserAttributes: [
    {
     Name: 'email',
     Value: email
    },
   ],
  };

  const data = await cognito.signUp(params).promise();
  console.log('SignUp success:', JSON.stringify(data)); // Log successful signup
  // Include CORS headers in the successful response
  return {
    statusCode: 200,
    headers: {
      "Access-Control-Allow-Origin": "*", // Adjust this value based on your requirements
      "Access-Control-Allow-Credentials": true, // If your client needs to handle cookies
    },
    body: JSON.stringify(data)
  };
 } catch (err: any) {
  console.error('SignUp error:', err); // Log any errors that occur
  // Include CORS headers in the error response
  return {
    statusCode: 400,
    headers: {
      "Access-Control-Allow-Origin": "*", // Adjust this value based on your requirements
      "Access-Control-Allow-Credentials": true, // If your client needs to handle cookies
    },
    body: JSON.stringify(err.message)
  };
 }
};

• Security of CORS Policy: Using "Access-Control-Allow-Origin": "*" allows any domain to make requests to your endpoint. For production environments, it's recommended to specify the exact origins that should be allowed to interact with your API.
• Credentials and Cookies: If your application uses cookies or authentication tokens that must be sent along with requests, you'll need to set "Access-Control-Allow-Credentials": true and specify the exact origin instead of "*" in the Access-Control-Allow-Origin header.
• Method-Specific Headers: If your application needs to handle other HTTP methods or custom headers, you might also need to include Access-Control-Allow-Methods and Access-Control-Allow-Headers in your response headers.

Adjusting your server response to include these CORS headers should help resolve the browser-reported CORS errors, ensuring that your application's frontend can correctly receive and process responses from your Lambda function.

User at 9:36 pm, Jun 29, 2024

So, the CORS problem we are seeing in the browser may have been a lack of CORS headers in the response this whole time, and not any kind fo CORS restrictions on the server?

Codeium at 9:36 pm, Jun 29, 2024

Yes, that's a correct understanding. The CORS problem you're observing in the browser is likely due to the lack of CORS headers in the responses from your server, rather than restrictions or misconfigurations on the server itself regarding CORS policy enforcement.

CORS (Cross-Origin Resource Sharing) is a security feature implemented by web browsers to prevent malicious websites from making requests to another domain without permission. When your frontend (running on one origin, such as http://localhost:5173) makes a request to your backend (hosted on a different origin, like https://u4ceo7qshi.execute-api.us-east-1.amazonaws.com), the browser automatically enforces CORS policy. It does this by checking for specific CORS headers (Access-Control-Allow-Origin, among others) in the response from the server.

If these headers are missing or do not correctly acknowledge the requesting origin, the browser blocks the response and shows a CORS error in the console. This can happen even if the server has processed the request successfully — for example, by registering a new user with AWS Cognito as in your signup function.

To resolve this issue and ensure that the browser accepts responses from your server:

• Include CORS Headers: Modify your server's responses to include the necessary CORS headers, as shown in the adjusted Lambda function code. This tells the browser that the response is allowed to be shared with the requesting origin.
• Specific vs. Wildcard Origins: For security, it's best to specify which origins are allowed rather than using a wildcard (*). This is especially important if your server is handling sensitive data or operations.
• Consider Preflight Requests: For certain types of requests, browsers send a preflight request (an OPTIONS request) before the actual request. Ensure your server correctly handles these preflight requests by responding with the appropriate CORS headers and a 200 OK or 204 No Content status.

By ensuring your server's responses include the correct CORS headers, you inform the browser that it's safe to pass the response data along to the web page making the request, thereby avoiding CORS errors.

User at 9:38 pm, Jun 29, 2024

And the signUp in the URL was preventing the account from being created and the email from being sent out.

So two different errors appeared like one phantom CORS restriction.

Codeium at 9:39 pm, Jun 29, 2024

Exactly, you've encountered a situation where two separate issues contributed to the confusion and manifested in a way that made it seem like a singular CORS restriction problem. Let's break down the two issues for clarity:

1. URL Case Sensitivity: The mismatch in case sensitivity (signUp vs. signup) was the first issue. URLs are case-sensitive, and this mismatch led to requests not being routed correctly to your intended handler function. This would prevent the account creation process from initiating, and thus, no email would be sent out. Correcting the URL path in your frontend to match the exact case as defined in your backend or API gateway configuration resolved this issue, allowing the signup process to proceed.

2. Lack of CORS Headers in Response: The second, distinct issue was the lack of CORS headers in the response from your server. Even after correcting the URL mismatch, the successful request from the browser would still fail at the client side due to CORS policy enforcement by the browser. This is because the server's response did not include the necessary Access-Control-Allow-Origin header (among potentially other needed CORS headers), leading the browser to block the response and display a CORS-related error message. Adding the appropriate CORS headers to your Lambda function’s responses resolved this issue, allowing the browser to accept the response.

The combination of these problems created a scenario where:

• Initially, requests failed silently because they were not reaching the intended endpoint due to the URL case mismatch.
• Once the URL was corrected, requests reached the server and triggered the intended functionality (e.g., user registration in Cognito), but the browser blocked the responses due to missing CORS headers, resulting in CORS error messages in the console.

This situation underscores the importance of attention to detail in web development, especially regarding URL path case sensitivity and CORS policies. It also highlights how unrelated issues can sometimes intersect to produce misleading or confusing symptoms, complicating troubleshooting efforts.

By addressing both issues—ensuring URL paths match exactly between frontend and backend and including the necessary CORS headers in server responses—you effectively resolved the problem, allowing for successful communication between your client-side application and the server.