Flask

Flask provider example.

This modules defines a simple provider which will be tested with Pact in the provider test. As Pact is a consumer-driven framework, the consumer defines the contract which the provider must then satisfy.

The provider is the application which receives requests from another service (the consumer) and returns a response. In this example, we have a simple endpoint which returns a user's information from a (fake) database.

Note that the code in this module is agnostic of Pact. The pact-python dependency only appears in the tests. This is because the consumer is not concerned with Pact, only the tests are.

Attributes

FAKE_DB: dict[int, User] = {} module-attribute

app = Flask(__name__) module-attribute

logger = logging.getLogger(__name__) module-attribute

Classes

User(id: int, name: str, created_on: datetime, email: str | None, ip_address: str | None, hobbies: list[str], admin: bool) dataclass

User data class.

Attributes

admin: bool instance-attribute

created_on: datetime instance-attribute

email: str | None instance-attribute

hobbies: list[str] instance-attribute

id: int instance-attribute

ip_address: str | None instance-attribute

name: str instance-attribute

Functions

dict() -> dict[str, Any]

Return the user's data as a dict.

Source code in examples/src/flask.py

def dict(self) -> dict[str, Any]:
    """
    Return the user's data as a dict.
    """
    return {
        "id": self.id,
        "name": self.name,
        "created_on": self.created_on.strftime("%Y-%m-%dT%H:%M:%S%z"),
        "email": self.email,
        "ip_address": self.ip_address,
        "hobbies": self.hobbies,
        "admin": self.admin,
    }

Functions

create_user() -> Response

Source code in examples/src/flask.py

@app.route("/users/", methods=["POST"])
def create_user() -> Response:
    if request.json is None:
        abort(400, description="Invalid JSON data")

    user: dict[str, Any] = request.json
    uid = len(FAKE_DB)
    FAKE_DB[uid] = User(
        id=uid,
        name=user["name"],
        created_on=datetime.now(tz=timezone.utc),
        email=user.get("email"),
        ip_address=user.get("ip_address"),
        hobbies=user.get("hobbies", []),
        admin=user.get("admin", False),
    )
    return jsonify(FAKE_DB[uid].dict())

delete_user(uid: int) -> tuple[str | Response, int]

Source code in examples/src/flask.py

@app.route("/users/<int:uid>", methods=["DELETE"])
def delete_user(uid: int) -> tuple[str | Response, int]:
    if uid not in FAKE_DB:
        return jsonify({"detail": "User not found"}), 404
    del FAKE_DB[uid]
    return "", 204

get_user_by_id(uid: int) -> Response | tuple[Response, int]

Fetch a user by their ID.

PARAMETER	DESCRIPTION
uid	The ID of the user to fetch TYPE: int

RETURNS	DESCRIPTION
Response | tuple[Response, int]	The user data if found, HTTP 404 if not

Source code in examples/src/flask.py

@app.route("/users/<int:uid>")
def get_user_by_id(uid: int) -> Response | tuple[Response, int]:
    """
    Fetch a user by their ID.

    Args:
        uid: The ID of the user to fetch

    Returns:
        The user data if found, HTTP 404 if not
    """
    user = FAKE_DB.get(uid)
    if not user:
        return jsonify({"detail": "User not found"}), 404
    return jsonify(user.dict())