Overriding dependencies in tests in FastAPI - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to override a FastAPI dependency in a test.

FastAPI

app.dependency_overrides[[1]] = override_dependency

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ADepends

Boverride_dependency

Capp

Dget_db

Attempts:

3 left

💡 Hint

Common Mistakes

Using the override function as the key instead of the original dependency.

Trying to override the app object itself.

In FastAPI, to override a dependency for testing, you assign your override function to app.dependency_overrides using the original dependency function as the key.

2fill in blank

medium

Complete the test client setup to use the overridden dependencies.

FastAPI

client = TestClient([1])

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Aapp

Boverride_dependency

Cget_db

DDepends

Attempts:

3 left

💡 Hint

Common Mistakes

Passing the override function instead of the app.

Passing the dependency function instead of the app.

The TestClient needs the FastAPI app instance to run tests with overridden dependencies.

3fill in blank

hard

Fix the error in the dependency override removal after the test.

FastAPI

app.dependency_overrides.[1](get_db)

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Apop

Bclear

Cdelete

Dremove

Attempts:

3 left

💡 Hint

Common Mistakes

Using remove which is not a dictionary method.

Using delete which is not a method.

Using clear which removes all overrides.

To remove a specific dependency override, use pop with the original dependency function as the key.

4fill in blank

hard

Fill both blanks to define a dependency override function that yields a test database session.

FastAPI

def override_dependency():
    db = [1]()
    try:
        yield db
    finally:
        db.[2]()

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ASessionLocal

Bclose

Ccommit

Drollback

Attempts:

3 left

💡 Hint

Common Mistakes

Using commit or rollback instead of close.

Not calling the session factory to create a session.

The override function creates a new session from SessionLocal and ensures it is closed after use with close().

5fill in blank

hard

Fill all three blanks to override a dependency, create a test client, and remove the override after the test.

FastAPI

app.dependency_overrides[[1]] = override_dependency
client = TestClient([2])
# run tests here
app.dependency_overrides.[3](get_db)

Drag options to blanks, or click blank then click option'

Aget_db

Bapp

Cpop

Doverride_dependency

Attempts:

3 left

💡 Hint

Common Mistakes

Using the override function as the key instead of the original dependency.

Passing the override function to TestClient instead of the app.

Using a wrong method like remove or delete instead of pop.

This pattern sets the override for get_db, creates a test client with the app, and removes the override using pop after tests.