/api_consumer

A showcase of external API integration considering important factors including, caching, validation and extensibility.

Primary LanguagePython

API consumer and processor

This codebase presents some guidelines on how to integrate an external API on a reliable manner.

Some notes:

Tests:

Generally speaking, integration to external APIs requires two levels of verification: Verifying that the API returns expected results when accessed according to its documentation. I used Marshmallow as a schema validator to validate returned values concerning API verification. Verifying app functionality after API verification. I used a mixture of mocking and stubbing to verify the business logic that happens inside the app, mainly nested_by_films method of People endpoint.

Integration testing against a sandbox server that replicates the actual API server is missing. In this case, instead of mocking external call responses, which is mainly done by using stub_request method of request_mock fixture, we can call the external sandbox server to check against the HTTP response code, HTTP headers in the response, and the payload.

Caching:

I used cachetools to cache the converted response data on list and retrieve methods of APIEndpoints, but a more extensible and cleaner approach exists too: Adding caching functionality inside APIRequester.request method.

The idea is simply defining a global cache policy using template design pattern for APIRequester class, which can be overwritten by the caller. inside APIRequester.request method, before the invocation of self._client.retry_request, it'll check the request against the cache policy and if a response was found in the cache policy it'll return it instead of calling the actual API. This is a work in progress on 'feat/caching-middleware' branch.

Getting Up and Running Locally

you can use docker to run the app on a container or install and run it locally.

1- install using docker

Prerequisites

  • Docker; if you don’t have it yet, follow the installation instructions;
  • Docker Compose; refer to the official documentation for the installation guide.

How to install:

1- Build the Stack: Open a terminal at the project root and run the following for local development:

$ docker-compose build

2- Run the docker-compose:

$ docker-compose up

you can access the API using the following url:

http://127.0.0.1:8080/movies

2- install locally without docker

Installing the app on your local machine, you can run tests and test coverage commands directly.

How to install:

2-1: Install poetry:

curl -sSL https://raw.githubusercontent.com/python-poetry/poetry/master/get-poetry.py | python

2-2: Installing dependencies:

make install

2-3: Run server:

make server

how to run tests:

  • Run test without overage report:
make test
  • Run test with overage report:
make coverage