Skip to main content

Micro-framework to allow incremental dependencies injection in inter-related modules.

Project description

Incremental Module Loader

Proposes a injection pattern for your modules. Each module is simply a callable which takes other named modules as arguments. It is very simple with less than 40 statements of code and allows a great deal of flexibility while still removing frequent boilerplate we had to write on each of our projects.

This module is used by our SpinHub App ( which is currently in development. It is the main building block of our module/service based architecture.

Use-Case 1: Modularize a flask app

You have an auth service, a database service and an blueprint creator function. How do you hook all of these together while keeping good separation of concerns and allowing injection of mocked services ? Let's see:

from incremental_module_loader import IncrementalModuleLoader

from flask import request, jsonify

class RequestParsingModule(object):
    def get_authorization_header(self):
        return request.headers.get('Authorization', None)

class MyAuthModule(object):
    def __init__(self, config, request_parser):
        self.url = config['AUTH_URL']
        self.request_parser = request_parser

    def get_user_id_from_token(self):
        header = request_parser.get_authorization_header()
        pass # Extract user id from header token...

class MyDatabaseModule(object):
    def __init__(self, config, auth):
        self.db_uri = config['SQLALCHEMY_DATABASE_URI']
        self.auth = auth

    def get_user(self):
        user_id = self.auth.get_user_id_from_token()
        pass # Retrieve user data from database...

# Note the name of the arguments here:
def route_app(app, config, database):

    def userinfo():
        # This triggers the auth verification from the header extracted from the request parser
        user = database.get_user()
        return jsonify(user.dump())
        # ...

def create_app():
    app = # (...) Standard app creation with config loading

    module_loader = IncrementalModuleLoader()

    # First init the modules with already created objects:

    # Then load in order ("incrementally")
    # Make sure to specify a CALLABLE object (function or class)
    # The module_loader will call the parameter with the modules it is asking as parameters.

    # Can be loaded anonymously, returns nothing.

    # There you have it !


Created by Tack Verification, a company dedicated to reducing operational costs related to hardware systems verification.

Project details

Release history Release notifications

Download files

Download the file for your platform. If you're not sure which to choose, learn more about installing packages.

Files for incremental-module-loader, version 1.0.0
Filename, size File type Python version Upload date Hashes
Filename, size incremental_module_loader-1.0.0-py3-none-any.whl (4.7 kB) File type Wheel Python version py3 Upload date Hashes View hashes
Filename, size incremental_module_loader-1.0.0.tar.gz (3.9 kB) File type Source Python version None Upload date Hashes View hashes

Supported by

Elastic Elastic Search Pingdom Pingdom Monitoring Google Google BigQuery Sentry Sentry Error logging AWS AWS Cloud computing DataDog DataDog Monitoring Fastly Fastly CDN DigiCert DigiCert EV certificate StatusPage StatusPage Status page