> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.
# Posts Fixture Create Test Posts
> This article explains how to create a fixture for adding initial posts to a database for testing purposes.
In this lesson, we will create a fixture to add initial posts to our database. This approach not only simplifies testing for retrieving, updating, deleting, and voting on posts, but it also establishes a reusable framework across different test modules.
Below is a preliminary test that retrieves all posts using an authorized client. The test prints the JSON response and asserts that the HTTP status code is 200.
```python theme={null}
def test_get_all_posts(authorized_client):
res = authorized_client.get("/posts/")
print(res.json())
assert res.status_code == 200
```
When running the tests, you may see output similar to the following:
```bash theme={null}
(venv) C:\Users\sanje\Documents\Courses\fastapi>pytest tests/test_posts.py -v -s
platform win32 -- Python 3.9.5, pytest-6.2.5, py-1.10.0, pluggy-1.0.0 -- c:\users\sanje\documents\courses\fastapi\venv\scripts\python.exe
cachedir: .pytest_cache
rootdir: C:\Users\sanje\Documents\Courses\fastapi
plugins: cov-2.12.1
collected 1 item
tests/test_posts.py::test_get_all_posts [] PASSED
```
You might also encounter warnings such as:
```plaintext theme={null}
================================= warnings summary =================================
venv\lib\site-packages\aiofiles\os.py:10
venv\lib\site-packages\aiofiles\os.py:10: DeprecationWarning: "@coroutine" decorator
```
Since our tests will involve operations like updating or deleting posts, having a dedicated fixture to create initial posts is essential. In our test file (for example, `tests/test_posts.py`), this fixture streamlines the setup process for tests that need initial post data.
Every post must be associated with a test user. Ensure that you have a test user fixture and an active database session before invoking the post fixture.
Below is the complete fixture for creating test posts. This fixture first defines our list of test post data as dictionaries and then uses the SQLAlchemy `add_all` method to add all posts in one go. The Python `map` function converts each dictionary into a model instance.
```python theme={null}
@pytest.fixture
def test_posts(test_user, session):
posts_data = [
{
"title": "first title",
"content": "first content",
"owner_id": test_user['id']
},
{
"title": "2nd title",
"content": "2nd content",
"owner_id": test_user['id']
},
{
"title": "3rd title",
"content": "3rd content",
"owner_id": test_user['id']
}
]
def create_post_model(post):
return models.Post(**post)
posts = list(map(create_post_model, posts_data))
session.add_all(posts)
session.commit()
posts = session.query(models.Post).all()
return posts
```
This fixture creates three posts in the database using the test user’s ID. You can now consistently use this fixture in any test requiring initial post data.
## Improved Test Using the Fixture
The following example demonstrates how to refactor our retrieval test to integrate the `test_posts` fixture:
```python theme={null}
from app import schemas
def test_get_all_posts(authorized_client, test_posts):
res = authorized_client.get("/posts/")
# Validate that the number of posts returned matches the number created by the fixture.
assert len(res.json()) == len(test_posts)
assert res.status_code == 200
```
## Validating Response Data with Pydantic Schemas
To leverage our Pydantic schemas for a more robust validation of the returned data, consider this enhanced approach. Here, a helper function named `validate` converts each dictionary in the response into a `PostOut` Pydantic model. This allows for detailed assertions on each post's data.
```python theme={null}
from app import schemas
def test_get_all_posts(authorized_client, test_posts):
res = authorized_client.get("/posts/")
def validate(post):
return schemas.PostOut(**post)
posts_map = map(validate, res.json())
posts_list = list(posts_map)
# Basic validations
assert len(res.json()) == len(test_posts)
assert res.status_code == 200
# Example: Validate that the first post's ID matches (if the order is predictable).
# If the retrieval order is not guaranteed, consider sorting or using alternative comparison methods.
assert posts_list[0].Post.id == test_posts[0].id
```
When executing the tests with this configuration, your console output will confirm that the posts are created, retrieved, and validated correctly:
```bash theme={null}
(venv) C:\Users\sanje\Documents\Courses\fastapi>pytest tests/test_posts.py -v -s
platform win32 -- Python 3.9.5, pytest-6.2.5, py-1.10.0, pluggy-1.0.0 -- C:\Users\sanje\Documents\Courses\fastapi\venv\Scripts\python.exe
cachedir: .pytest_cache
rootdir: C:\Users\sanje\Documents\Courses\fastapi
plugins: cov-2.12.1
collected 1 item
tests/test_posts.py::test_get_all_posts [{'Post': {'title': '2nd title', 'content': '2nd content', 'published': True, 'id': 2, 'owner_id': 1, 'owner': {...}}, {...}, ...] PASSED
```
If the order of posts retrieved from the database is non-deterministic, consider sorting the results or modifying the assertions to ensure accurate comparisons.
By centralizing the post creation logic through this fixture, you not only simplify the testing environment but also enhance the maintainability of your tests, ensuring smooth transitions as your application evolves.
For additional information on testing best practices and related topics, check out our [Kubernetes Basics](https://kubernetes.io/docs/concepts/overview/what-is-kubernetes/) and [Kubernetes Documentation](https://kubernetes.io/docs/) pages.