Auth and Queues + Stacks

Queues and Stacks

Abstract Data Structures

• What is an Abstract Data Structure?
• Only defined by its behavior, not a specific implementation.

Stack:

• A stack has the behavior: FILO / LIFO
  • Whatever object is pushed in first, will be the last to be popped.
    • Push (adds an item to the stack)
    • Pop (removes an item from the stack)
    • Peek (look at whats in the stack)
    • Top and a bottom.

Queue

• Follow the reverse behavior: FIFO
• Whatever object is enqueued into the queue will be the first object to be dequeued.
  • Enqueue (adds an time to the rear of the queue)
  • Dequeue (removes an item from the front)
  • Tracks a rear and a front.

Request --> Middelware --> Response

app.get('/users', requestTime, handleUsers)

Auth

• Authentication: Who are you?
• Authorization: Are you allowed to do what you are trying to do? (based on who you are)

String Based Authentication

• We have the user make a user object:
  • username
  • password
  • Sent to our service as encrypted strings.
• Then we need to parse the string and decide is this a new user or an existing user.
• Creating a one way encrypted token, which the user can store and use for all auth requests.