Html_form_to_dict(): simple e2e testing

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I released a new version of html_form_to_dict()

Python2 is now supported, too. So you can test your old code before upgrading to Python3.

HTML Form to Dict

This is a tiny library which provides a method called html_form_to_dict().

This method takes a string containing HTML and returns a dictionary of the value of the first form.

The data returned by html_form_to_dict() is a FormDict which has the method submit(). This way
you can submit the data like a real browser would.

The submit() method supports the “action” and “method” attributes of forms and additionaly the htmx attributes hx-get, hx-post.

Example:

def test_foo(client):
    ...
    
    # client is a DjangoClient. But you could use
    # python-requests or a different URL-lib, too
    response = client.get(url)
    
    # This method parses the HTML in response.content to a dictionary
    data = html_form_to_dict(response.content)
    
    # Now you can test the default values of the form.
    assert data == {'city': 'Chemnitz', 'name': 'Mr. X'}
    
    # You can edit the data. This is like a human (or Playwright/Selenium)
    # altering the HTML input fields
    data['name'] = 'Mrs. Y'
    
    # This submits the data to the server.
    # This methods uses the "action" attribute of the form.
    # The hx-get, hx-post attributes of htmx are supported, too
    response = data.submit(client)
    
    # If you use the Post/Redirect/Get pattern:
    assert response.status == 302, response.context['form'].errors

Above code uses pytest-django. See client fixture

The FormDict returned by html_form_to_dict() does not allow adding new
keys, which are not in the dictionary yet. This way you get an error if your
test sets the value for an input which (maybe due to refactoring) does not exist.

Above example uses Django, but the library is a pure Python library which does not depend on any
particular web-framework.

This library was build for testing, but you can use it for all tasks where you
want to parse and submit html forms.

This library does not evaluate JavaScript. If you need JS support, please use Playwright (or a similar tool).

Install

pip install html_form_to_dict

Feedback is welcome

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