rest-api

Rest Api

Implement a RESTful API for tracking IOUs.

Four roommates have a habit of borrowing money from each other frequently, and have trouble remembering who owes whom, and how much.

Your task is to implement a simple RESTful API that receives IOUs as POST requests, and can deliver specified summary information via GET requests.

API Specification

User object

{
  "name": "Adam",
  "owes": {
    "Bob": 12.0,
    "Chuck": 4.0,
    "Dan": 9.5
  },
  "owed_by": {
    "Bob": 6.5,
    "Dan": 2.75,
  },
  "balance": "<(total owed by other users) - (total owed to other users)>"
}

Methods

Description	HTTP Method	URL	Payload Format	Response w/o Payload	Response w/ Payload
List of user information	GET	/users	{"users":["Adam","Bob"]}	{"users":<List of all User objects>}	{"users":<List of User objects for <users>>}
Create user	POST	/add	{"user":<name of new user (unique)}	N/A	<User object for new user>
Create IOU	POST	/iou	{"lender":<name of lender>,"borrower":<name of borrower>,"amount":5.25}	N/A	{"users":<updated User objects for <lender> and <borrower>>}

Other Resources:

• https://restfulapi.net/
• Example RESTful APIs
  • GitHub
  • Reddit

Exception messages

Sometimes it is necessary to raise an exception. When you do this, you should include a meaningful error message to indicate what the source of the error is. This makes your code more readable and helps significantly with debugging. Not every exercise will require you to raise an exception, but for those that do, the tests will only pass if you include a message.

To raise a message with an exception, just write it as an argument to the exception type. For example, instead of raise Exception, you should write:

raise Exception("Meaningful message indicating the source of the error")

Running the tests

To run the tests, run the appropriate command below (why they are different):

• Python 2.7: py.test rest_api_test.py
• Python 3.4+: pytest rest_api_test.py

Alternatively, you can tell Python to run the pytest module (allowing the same command to be used regardless of Python version): python -m pytest rest_api_test.py

Common pytest options

• -v : enable verbose output
• -x : stop running tests on first failure
• --ff : run failures from previous test before running other test cases

For other options, see python -m pytest -h

Submitting Exercises

Note that, when trying to submit an exercise, make sure the solution is in the $EXERCISM_WORKSPACE/python/rest-api directory.

You can find your Exercism workspace by running exercism debug and looking for the line that starts with Workspace.

For more detailed information about running tests, code style and linting, please see Running the Tests.

Submitting Incomplete Solutions

It's possible to submit an incomplete solution so you can see how others have completed the exercise.