Using Behave

Behave is a Behavior-Driven Development (BDD) testing framework that allows you to write tests in a natural language style using Gherkin syntax. This section explains how to write scenarios with Behave in the Cloud QA project.

Gherkin Syntax

Behave tests are written in feature files using Gherkin syntax, which follows this structure:

Feature: Name of the feature
  As a [role]
  I want [feature]
  So that [benefit]

  Scenario: Specific scenario name
    Given [precondition]
    When [action]
    Then [expected result]

The main components are:

  • Feature: Describes the feature being tested with a business value

  • Scenario: A specific test case for the feature

  • Given: Sets up the preconditions

  • When: Describes the action being performed

  • Then: Describes the expected outcome

  • And and But: Used for additional conditions

Example Feature File

Here’s an example from the Cloud QA project:

# features/api/user/user_creation.feature
Feature: User creation API
  As an admin
  I want to create new users
  So that they can access the platform

  Scenario: Create a new user with valid data
    Given I am logged in as admin
    When I create a user with the following data:
      | username | email           | role    |
      | newuser  | new@example.com | regular |
    Then the response status is "201"
    And the response contains a user with username "newuser"

Writing Scenarios

When writing scenarios, follow these best practices:

  1. Be specific: Each scenario should test one thing

  2. Use descriptive names: Make it clear what is being tested

  3. Focus on behavior: Test what the feature does, not how it’s implemented

  4. Keep it simple: Avoid complex scenarios with many steps

  5. Use tables for data: Data tables make tests more readable and maintainable

Running Behave Tests

To run all tests:

behave

To run specific feature:

behave features/api/user/user_creation.feature

To run tests with specific tags:

behave --tags=user,create

Step Implementation

The steps you write in your feature files are implemented in Python files in the features/steps directory. For example:

@given('I am logged in as admin')
def step_impl(context):
    context.cloud.login_as_admin()

@when('I create a user with the following data')
def step_impl(context, table):
    user_data = context.table[0]
    context.response = context.cloud.create_user(user_data)

@then('the response status is "{status}"')
def step_impl(context, status):
    assert context.response.status_code == int(status)