Setting up a dev environment

Pre-requisites

You can follow the pre-requisites instructions from the production guide, but do not create a mastodon user. You also don’t have to install nginx, certbot and python-certbot-nginx as the development environment brings its own webserver. Setting up and running a development environment has been proven successful over WSL2 as well if you are on Windows.

Setup

Run following commands in the project directory bundle install, yarn install.

In the development environment, Mastodon will use PostgreSQL as the currently signed-in Linux user using the ident method, which usually works out of the box. The one command you need to run is rails db:setup which will create the databases mastodon_development and mastodon_test, load the schema into them, and then create seed data defined in db/seed.rb in mastodon_development. The only seed data is an admin account with the credentials admin@localhost:3000 / mastodonadmin.

Please keep in mind, by default Mastodon will run on port 3000. If you configure a different port for it, the generated admin account will use that number.

If rails db:setup gives you the Postgres error:

ActiveRecord::NoDatabaseError: FATAL:  role "your_user_name" does not exist

(where your_user_name is your username), then run:

sudo -u postgres createuser your_user_name --createdb

This will create the necessary Postgres user with the permission to create a database.

Running

There are multiple processes that need to be run for the full set of Mastodon’s functionality, although they can be selectively omitted. To run all of them with just one command, you can install Foreman with gem install foreman --no-document and then use:

foreman start

In the Mastodon directory. This will start processes defined in Procfile.dev, which will give you: A Rails server, a Webpack server, a streaming API server, and Sidekiq. Of course, you can run any of those things stand-alone depending on your needs.

Testing

Last updated October 17, 2020 · Improve this page