Best way to handle flask POST unit test

Question

I have the following code, that accepts a POST request and processes it.

index.py

@app.route('/route', methods=['POST'])
def route_post():
    try:
        data = request.get_data()
        j = json.loads(data)
    except Exception as e:
    ...

Basically, I want access to request.get_data() so I can change the value. I'm invoking the test as shown below, which is dead simple.

route_test.py:

def test_route():
    assert(("Bad Request\r\n", 400) == route_post())

But doesn't allow me to set the value of request.get_data(). How can I do this?

Answer 1

Use the test client to post whatever data you need to the route. If data is a string or bytes, Werkzeug sends the data directly, as bytes.

from flask import Flask, request

app = Flask(__name__, static_folder=None)

@app.route('/', methods=['POST'])
def index():
    return request.get_data()

c = app.test_client()
r = c.post('/', data='Hello, World!')
print(r.data)  # b'Hello, World!'

Answer 2

You can patch method get_data of the request object with a mock object that returns what you tell it to return. Something along the lines of:

from mock import patch

@patch('flask.Request.get_data')
def test_route_post(self, get_deta_mock):
    get_deta_mock.return_value = '{"foo": "bar"}'
    result = route_post()
    assert result['foo'] == 'bar'