The two core components of Journey, route and BlueprintBundle, are not dependent on each other, however, there might be code added in the future that will enable them to integrate.

This, and the fact that they operate in the same field was the motivation for adding both to this extension.


Use pip to install the extension:

$ pip install flask-journey

Journey Usage

This step is only necessary if you plan on using the BlueprintBundle

The extension is managed through a Journey instance. If utilizing application factories, then you probably want to go the init_app() route:

from flask import Flask
from flask_journey import Journey

from .bundles import bundle1, bundle2

app = Flask(__name__)
journey = Journey()

You may also set up Journey directly, passing a list of bundles its constructor:

app = Flask(__name__)
journey = Journey(app, bundles=[bundle1, bundle2])

The route decorator

The route component, as mentioned previously, is not dependent on the Journey blueprint manager. However, functions decorated with flask_journey.route can of course, just as flask.Blueprint.route, be added to your app with the help of Journey.

Marshmallow compatible schemas:

# file: api/users/schemas.py

from marshmallow import Schema, fields, validate

class QuerySchema(Schema):
    first_name = fields.String(required=False)
    last_name = fields.String(required=False)

class UserSchema(Schema):
    id = fields.Integer(required=True)
    first_name = fields.String(required=True)
    last_name = fields.String(required=True)
    user_name = fields.String(required=True)

users = UserSchema(many=True)
user = UserSchema()
query = QuerySchema()

…with the flask_journey.route decorator enables simple (de)serialization and validation:

# api/users/controllers.py

from flask import Blueprint
from flask_journey import route

from .services import create_user, get_user, update_user
from .schemas import user, users, query

bp = Blueprint('users', __name__)

@route(bp, '/', methods=['GET'], _query=query, marshal_with=users)
def get_many(_query):
    return get_users(_query.data)

@route(bp, '/', methods=['POST'], _body=user, marshal_with=user)
def create(_body):
    return create_user(_body.data)

@route(bp, '/<user_id>', methods=['PUT'], _body=user, marshal_with=user)
def update(user_id, _body):
    return update_user(user_id, _body.data)


Bundling blueprints

There are various benefits of using the Journey BlueprintBundle, and in most cases just one BlueprintBundle is enough.

  • It can be used to easily segregate your blueprint registration code from the other parts of your application.
  • It helps you group blueprints in a logical manner.
  • It enables you to utilize the Journey API (currently only for blueprint bundle registration and listing routes)
# file: api/bundles.py

from flask_journey import BlueprintBundle

from .users import bp as users
from .groups import bp as groups
from .companies import bp as companies
from .stuff import bp as stuff

v1 = BlueprintBundle(path='/api/v1', description="API v1, stable")
v1.attach_bp(users, description='Users CRUD')
v1.attach_bp(companies, description='Companies API')

other = BlueprintBundle(path='/other')

Importing bundles

Importing and registering bundles (along with blueprints) is easy as pie:

# file: api/__init__.py

from flask import Flask
from .bundles import v1, other

app = Flask(__name__)
journey = Journey()

API Documentation

Journey API

class flask_journey.Journey(app=None, bundles=None)

Central controller class. Exposes an API for managing blueprints and listing routes


app – App to pass directly to Journey

  • InvalidBundlesType if passed bundles is not of type list

Attaches a bundle object


bundleflask_journey.BlueprintBundle object

  • IncompatibleBundle if the bundle is not of type BlueprintBundle
  • ConflictingPath if a bundle already exists at bundle.path
  • MissingBlueprints if the bundle doesn’t contain any blueprints
static get_blueprint_routes(app, base_path)

Returns detailed information about registered blueprint routes matching the BlueprintBundle path

  • app – App instance to obtain rules from
  • base_path – Base path to return detailed route info for

List of route detail dicts

static get_bp_path(bp)

Returns url_prefix if set, otherwise bp.name prefixed with a slash.

Parameters:bpflask.Blueprint object
Returns:blueprint name

Initializes Journey extension


app – App passed from constructor or directly to init_app

  • NoBundlesAttached if no bundles has been attached attached

Returns a detailed list of bundles along with blueprints and routes

Returns:List of blueprint routes

Returns simple info about registered blueprints

Returns:Tuple containing endpoint, path and allowed methods for each route

Route decorator

flask_journey.utils.route(bp, *args, **kwargs)

Journey route decorator

Enables simple serialization, deserialization and validation of Flask routes with the help of Marshmallow.

  • bpflask.Blueprint object
  • args – args to pass along to Blueprint.route
  • kwargs
    • strict_slashes:Enable / disable strict slashes (default False)
    • validate:Enable / disable body/query validation (default True)
    • _query:Unmarshal Query string into this schema
    • _body:Unmarshal JSON body into this schema
    • marshal_with:Serialize the output with this schema
  • ValidationError if the query parameters or JSON body fails validation

Performs sanitation of the path after validating


path – path to sanitize



  • InvalidPath if the path doesn’t start with a slash

BlueprintBundle API

class flask_journey.BlueprintBundle(path='/', description='')

Creates a BlueprintBundle at the path specified

Parameters:path – blueprint base path
attach_bp(bp, description='')

Attaches a flask.Blueprint to the bundle

  • bpflask.Blueprint object
  • description – Optional description string
  • InvalidBlueprint if the Blueprint is not of type flask.Blueprint


exception flask_journey.exceptions.ConflictingPath
exception flask_journey.exceptions.IncompatibleBundle
exception flask_journey.exceptions.IncompatibleSchema
exception flask_journey.exceptions.InvalidBlueprint
exception flask_journey.exceptions.InvalidBundlesType
exception flask_journey.exceptions.InvalidPath
exception flask_journey.exceptions.MissingBlueprints
exception flask_journey.exceptions.NoBundlesAttached