Simple mock server for testing using Flask

README.md

Mock server for testing using flask

License

MIT

Prepare

Install flask and requests to run this example.

mockserver.py

import requests

from flask import Flask, jsonify
from threading import Thread


class MockServer(Thread):
    def __init__(self, port=5000):
        super().__init__()
        self.port = port
        self.app = Flask(__name__)
        self.url = "http://localhost:%s" % self.port

        self.app.add_url_rule("/shutdown", view_func=self._shutdown_server)

    def _shutdown_server(self):
        from flask import request
        if not 'werkzeug.server.shutdown' in request.environ:
            raise RuntimeError('Not running the development server')
        request.environ['werkzeug.server.shutdown']()
        return 'Server shutting down...'

    def shutdown_server(self):
        requests.get("http://localhost:%s/shutdown" % self.port)
        self.join()

    def add_callback_response(self, url, callback, methods=('GET',)):
        callback.__name__ = str(uuid4())  # change name of method to mitigate flask exception
        self.app.add_url_rule(url, view_func=callback, methods=methods)

    def add_json_response(self, url, serializable, methods=('GET',)):
        def callback():
            return jsonify(serializable)
        
        self.add_callback_response(url, callback, methods=methods)

    def run(self):
        self.app.run(port=self.port)

requirements.txt

flask
requests

tests.py

import unittest
import requests

from mockserver import MockServer


class TestMockServer(unittest.TestCase):
    def setUp(self):
        self.server = MockServer(port=1234)
        self.server.start()

    def test_mock_with_json_serializable(self):
        self.server.add_json_response("/json", dict(hello="welt"))

        response = requests.get(self.server.url + "/json")

        self.assertEqual(200, response.status_code)
        self.assertIn('hello', response.json())
        self.assertEqual('welt', response.json()['hello'])

    def test_mock_with_callback(self):
        self.called = False

        def callback():
            self.called = True
            return 'Hallo'

        self.server.add_callback_response("/callback", callback)

        response = requests.get(self.server.url + "/callback")

        self.assertEqual(200, response.status_code)
        self.assertEqual('Hallo', response.text)
        self.assertTrue(self.called)

    def tearDown(self):
        self.server.shutdown_server()


if __name__ == '__main__':
    unittest.main()