Using Intern to unit test Ajax calls - msssk/intern GitHub Wiki

When writing unit tests with Intern, occasionally you will need to interact with a Web service using XMLHttpRequest. However, because the test runner serves code localhost:9000 by default, any cross-origin requests will fail. In order to test Ajax requests without using CORS or JSONP, the solution is to set up a reverse proxy to Intern and tell the test runner to load from that URL instead. You can either set up the Web server to only send requests to Intern for your JavaScript files, or you can set up the Web server to send all requests to Intern except for the Web services you’re trying to access.

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Option 1: All traffic except Web services to Intern

1. Modify the proxyUrl in your Intern configuration to point to the URL where the Web server lives
2. Set up the Web server to reverse proxy to http://localhost:9000/ by default
3. Add location directives to pass the more specific Web service URLs to the Web service instead

An nginx configuration implementing this pattern might look like this:

server {
  server_name proxy.example;

  location /web-service/ {
    # This will proxy to http://www.web-service.example/web-service/<rest of url>;
    # use `proxy_pass http://www.web-service.example/` to proxy to
    # http://www.web-service.example/<rest of url> instead
    proxy_pass http://www.web-service.example;
  }

  location / {
    proxy_pass http://localhost:9000;
  }
}

Option 2: Only JavaScript traffic to Intern

1. Modify the proxyUrl in your Intern configuration to point to the URL where the Web server lives
2. Set up the Web server to reverse proxy to http://localhost:9000/ for the special /__intern/ location, plus any directories that contain JavaScript

An nginx configuration implementing this pattern might look like this:

server {
  server_name proxy.example;
  root /var/www/;

  location /js/ {
    proxy_pass http://localhost:9000;
  }

  location /__intern/ {
    proxy_pass http://localhost:9000;
  }

  location / {
    try_files $uri $uri/ =404;
  }
}

Reverse proxy configuration information for common Web servers:

• nginx
• Apache 2
• IIS