Pytest: testing Flask echo POST

Here we can observe how to send data to a “POST” request in a test.

In this case we used a class to write the test. I’d probably prefer the procedural tests as we saw in the previous example, but I wanted to show this as well.

We create a new attribute called “flapp” for the class, something you would not be able to do it stricter languages such as Java. We can only hope that the existing object does not have such an attribute and we are not ruining the class.

import echo_post

class TestEcho:
    def setup_method(self):
        self.flapp = echo_post.app.test_client()
        print("setup")

    def test_main_page(self):
        rv = self.flapp.get('/')
        assert rv.status == '200 OK'
        assert '<form action="/echo" method="POST">' in rv.data.decode('utf-8')

    def test_echo_get(self):
        rv = self.flapp.get('/echo')
        assert rv.status == '405 METHOD NOT ALLOWED'
        assert '<title>405 Method Not Allowed</title>' in rv.data.decode('utf-8')

    def test_echo_post_empty(self):
        rv = self.flapp.post('/echo')
        assert rv.status == '200 OK'
        assert b"Nothing to say?" == rv.data

    def test_echo_post_with_data(self):
        rv = self.flapp.post('/echo', data={ "text": "foo bar" })
        assert rv.status == '200 OK'
        assert b"You said: foo bar" == rv.data

    def test_echo_404(self):
        rv = self.flapp.get('/qqrq')
        assert rv.status == '404 NOT FOUND'
        assert b'The requested URL was not found on the server.' in rv.data