Money Printer Server

The server application for the Money Printer, written in Python and backed to MySQL, using Redis as a transport backbone.

Consists of a handful of services:

• data server
• task runner
• api

Data Server

The data server is a threaded server that listens to client requests from the api and services them by dispatching requests to a variety of upstream services, specifically IEX via SSE, and proxies the results back to the api, backboned by Redis.

Task Runner

A threaded server that services a work queue backed by Redis. Various services such as the API push jobs into the Redis queue and the task runner pulls jobs off and executes them.

The task runner server is also responsible for scheduling and running tasks from stored jobs. These are scheduled as messages onto the task runner queue.

API

Money Printer provides both a full REST-full API service, and a more limited GraphQL API service.

The REST-full service is intended to fulfill all internal application and external integrating partner needs.

The GraphQL service provides read-only access to the authed user's app specific data.

REST

The main RESTful HTTP API server implemented in Flask that services the bulk of client requests. Supports RESTful and web socket requests. All private resources secured by JWT based authentication.

Documentation for the api can be found at http://localhost/api/v1/ via SwaggerUI when the application is running in a non production mode.

GraphQL

GraphQL is integrated through graphene, and the GraphQL endpoint can be found at http://localhost/api/v1/graphql.

When the application is running in a non production mode, the GraphQL serves a GraphQLi web query interface.

Development setup

3rd Party Dependencies

Money Printer depends on the following 3rd party services, which you will need API keys for:

• IEXCloud
• Mailgun
• Plaid

IEXCloud

Money Printer uses IEX Cloud for both historical stock market price querying and real time stock market price streaming. This is a pretty fundamental part of the application and is required.

Mailgun

Money Printer uses email to communicate non-real time messages. Failing to provide valid Mailgun creds will result in initialization failing to deliver your password, but that can be worked around with minimal effort in the source.

Plaid

Plaid is used to sync account holdings and balances for the more wealth planning feature set. This can be optionally written out if you're willing to keep your own accounts in sync, though no UI exists for that yet. Nor API endpoints.

Development

Money Printer is a containerized application, most of the dev tasks should be easily accomplishable with Docker.

This server project also includes a package.json file that defines tasks that enable you to easily work with Docker.

Regardless of how you choose to interact with Docker, this project has a separate definition for development vs. production. By running the docker-compose.dev.yml file, you'll receive:

• a local, persistant MySQL database server
• a local redis server
• local /src directory mounted to enable hot code reloading
• an automatic ngrok tunnel to ensure webhook integration with Plaid works properly in local development
• a full production style, auto-configured stack for Prometheus and Matomo to test metrics and stats tracking

ngrok

Plaid uses webhooks to keep integration consumers up to date with their client's token statuses, such as when the user has changed their auth passwords or closed accounts.

The nature of working on a local development machine presents challenges when working with webhooks, hence ngrok.

ngrok will open a tunnel to the public internet to the API running on your local machine, and the API code looks for the MP_WEBHOOK_HOST environment variable to determine how to link the webhooks up for Plaid. This will enable Plaid to send webhooks from their test environment into your local development environment.

ngrok also offers a UI from which you can observe a log of incoming requests.

This is a development specific service, so will not run when the application is launched in production mode.

The ngrok UI is available at http://localhost:4040/ when running.

Prometheus

Prometheus is integrated as a way of tracking internal app performance metrics.

Money Printer has been instrumented with Prometheus to track the performance of all public API endpoints and most internal discrete repository level commands. A subset of actions has also been instrumented.

Instrumentation is not free, and while we should ensure we have a good idea of how the various parts of the application are performing, we shouldn't instrument it so much that the instrumentation affects performance.

Prometheus is available at http://localhost:9090/ when running.

Matomo

Matomo provides Google Analytics style tracking through our application, but it's all local and much more respective of the user's privacy.

We use Matomo to track performance of various UX elements and flows through out the application. The goal of the Matomo analytics is to improve the functionality and UX of the application, not to mine data about the users to sell.

As part of tracking for marketing purposes, we do collect some demographic information about our user base, but that information is private.

Matomo is available at http://localhost:8080/ when running.

Environment setup

• install Docker Desktop
• install any recent-ish version of Node for task management (optional)
• ensure you've build the docker images in money-printer-infrastructure
• edit hosts file (below) to access services through the reverse proxy
• either run npm run start or docker compose -f docker-compose.dev.yml up -d

Hosts

• Windows *

In an Administrator privilleged text editor, open the C:\Windows32\drives\etc\hosts file and add the following entries:

127.0.0.1 mp-ngrok.local
127.0.0.1 mp-matomo.local
127.0.0.1 mp-prometheus.local
127.0.0.1 mp-hasura.local
127.0.0.1 mp-api.local
127.0.0.1 mp-stonks.local

• Unix/Mac OS*

In a sudo text editor, open /etc/hosts and add the following entries:

127.0.0.1 mp-ngrok.local
127.0.0.1 mp-matomo.local
127.0.0.1 mp-prometheus.local
127.0.0.1 mp-hasura.local
127.0.0.1 mp-api.local
127.0.0.1 mp-stonks.local

Available npm commands

• npm run start - start the Docker compose project
• npm run stop - stop and pull down the Docker compose project
• npm run build - build the Docker compose project
• npm run recycle - stop, down, build, start the Docker compose project
• npm run db:init - initialize the db, only useful when initially setting up the project
• npm run db:migrate - create a new migration for the database against the db container
• npm run db:update - apply all pending updates to a running db container
• npm run test - run the entire server test suite
• npm run test:focus - run tests marked with @pytest.mark.focus, useful for isolating troublesome tests
• npm run gendoc - run the OpenAPI spec generation on a running API
• npm run clean - remove all local pycache and pre-compiled Python objects

The start, stop, build, and recycle tasks have :prod variants that can be used to stand up the application in production mode. This is useful for testing behavioral differences when running locally vs. prod, however the prod docker-compose.prod.yml file won't create a local DB, so ensure your .env.dev file is pointing to a valid and accessible Money Printer development database server.

Deploying

TBD