🏁 Flagsmith

AwesomeFOSS Team

Mar 3, 2024 • 5 min read

Flagsmith (code) is an open source, fully featured, Feature Flag and Remote Config service. Not sure what a feature flag is or why you'd want a service for managing them? LaunchDarkly has a great post on this:

We'll also steal their awesome intro to feature flags (though this article is about Flagsmith!):

You might see what we're getting at here – Flagsmith is like fully F/OSS versino of LaunchDarkly (though of course the LD team would probably beg to differ, on feature set basis at least!).

We'll sum it up for the impatient: feature flags let you separate deploying features and enabling features, by standardizing on a means of turning feature integration on and off without redeploying your code.

We love products with Demos, and Flagsmith has one:

🌠 Features

Flagsmith has a ton of features (and they're all turned on):

Fully featured Web GUI for managing flags
BSD 3-clause license
Scheduling of flag setting
Managed change requests for flags
Segmenting usebase for flagging
Environment management (ex. Dev/Staging/Production)
Easy deployment with Docker
Client SDKs in many programming languages

🤖 As described by AI

Flagsmith offers a comprehensive platform for managing feature flags and remote configurations, enabling teams to implement and control features across various environments seamlessly. It supports A/B testing, segment targeting, and feature rollouts, enhancing the development process by allowing real-time adjustments without code deployments.

Flagsmith emphasizes security and flexibility, offering deployment options that cater to different organizational needs. With its open-source nature, Flagsmith encourages community contributions and development, fostering an ecosystem where developers can share improvements, ensuring the platform remains at the forefront of feature flagging technology.

📺 Watch this

Flagsmith has a YouTube channel which has some great guides and content on it to check out.

There's a great demo on how to do A/B testing with Flagsmith:

If you're more into live-streamed code and hijinks, you might like this recent video by Eddie Jaoude, with Flagsmith:

👟 Getting started

Flagsmith is easy to get started with for a couple reasons:

Great docker support, so it's easy to experiment without changing your system too much
docker-compose support (you can start Flagsmith and it's dependencies all at once)
Kubernetes support for those who use k8s

🐳 Deploying Flagsmith with Docker

Rather than reading what we have to say, you might want to check out the Flagsmith Docker deployment docs:

Docker | Flagsmith Docs

Getting Started with Flagsmith on Docker

Flagsmith

Flagsmith has an official docker image and a docker-compose.yml file that is easy to read and use in their repository:

We've reproduced the Flagsmith relevant parts below (and removed postgres for example, the backing datastore):

version: '3'

services:
  flagsmith:
    image: flagsmith/flagsmith:latest
    environment:
      # All environments variables are available here:
      # API: https://docs.flagsmith.com/deployment/locally-api#environment-variables
      # UI: https://docs.flagsmith.com/deployment/locally-frontend#environment-variables

      DATABASE_URL: postgresql://postgres:password@postgres:5432/flagsmith
      USE_POSTGRES_FOR_ANALYTICS: 'true' # Store API and Flag Analytics data in Postgres

      ENVIRONMENT: production # set to 'production' in production.
      DJANGO_ALLOWED_HOSTS: '*' # Change this in production
      ALLOW_ADMIN_INITIATION_VIA_CLI: 'true' # Change this in production
      FLAGSMITH_DOMAIN: localhost:8000 # Change this in production
      DJANGO_SECRET_KEY: secret # Change this in production
      # PREVENT_SIGNUP: 'true' # Uncomment to prevent additional signups
      # ENABLE_ADMIN_ACCESS_USER_PASS: 'true' # Uncomment to enable access to the /admin/ Django backend via your username and password
      # ALLOW_REGISTRATION_WITHOUT_INVITE: 'true'

      # Enable Task Processor
      TASK_RUN_METHOD: TASK_PROCESSOR # other options are: SYNCHRONOUSLY, SEPARATE_THREAD (default)

      # For more info on configuring E-Mails - https://docs.flagsmith.com/deployment/locally-api#environment-variables
      # Example SMTP:
      # EMAIL_BACKEND: django.core.mail.backends.smtp.EmailBackend
      # EMAIL_HOST: mail.example.com
      # SENDER_EMAIL: flagsmith@example.com
      # EMAIL_HOST_USER: flagsmith@example.com
      # EMAIL_HOST_PASSWORD: smtp_account_password
      # EMAIL_PORT: 587 # optional
      # EMAIL_USE_TLS: 'true' # optional
    ports:
      - 8000:8000
    healthcheck:
      test: ['CMD-SHELL', 'python /app/scripts/healthcheck.py']
      interval: 2s
      timeout: 2s
      retries: 20
      start_period: 20s
    depends_on:
      postgres:
        condition: service_healthy

  # The flagsmith_processor service is only needed if TASK_RUN_METHOD set to TASK_PROCESSOR
  # in the application environment
  flagsmith_processor:
    image: flagsmith/flagsmith:latest
    environment:
      DATABASE_URL: postgresql://postgres:password@postgres:5432/flagsmith
      USE_POSTGRES_FOR_ANALYTICS: 'true'
    depends_on:
      flagsmith:
        condition: service_healthy
    command: run-task-processor

As you can see there are two main pieces to a Flagsmith installation:

Flagsmith main (docker image flagsmith/flagsmith with the default command)
Flagsmith task processor (docker image flagsmith/flagsmith run with the command run-task-processor)

This is a pretty standard setup for software that also has a job processor or some sort of async task queue, and it's quite well put together and easy to follow for Flagsmith.

🧑‍💻 Want to contribute?

Flagsmith is truly free software (BSD 3-clause license), and accepts contributions and bug reports:

There are over 200 issues outstanding (and over 800 closed!) so jump in and help out if you're so inclined.