Getting Started.md

Getting started

Installation

Commanded scheduler can be installed from hex as follows.

1. Add commanded_scheduler to your list of dependencies in mix.exs:

   def deps do
     [{:commanded_scheduler, "~> 0.2"}]
   end

2. Fetch mix dependencies:

   mix deps.get

Configuration

Commanded scheduler uses its own Ecto repo for persistence.

You must configure the database connection settings for the Ecto repo in the environment config files:

# config/config.exs
config :commanded_scheduler, Commanded.Scheduler.Repo,
  adapter: Ecto.Adapters.Postgres,
  database: "commanded_scheduler_dev",
  username: "postgres",
  password: "postgres",
  hostname: "localhost",
  pool_size: 1

You can use an existing database for the Scheduler. It will create a table named schedules to store scheduled commands and a projection_versions, if not present, used for Commanded's read model projections.

Create Commanded scheduler database

Once configured, you can create and migrate the scheduler database using Ecto's mix tasks.

Specify the Commanded scheduler's Ecto repo for the mix tasks using the --repo or -r command line option:

mix ecto.create --repo Commanded.Scheduler.Repo
mix ecto.migrate --repo Commanded.Scheduler.Repo

Alternatively, you can include Commanded.Scheduler.Repo in the ecto_repos config for your own application:

# config/config.exs
config :my_app,
  ecto_repos: [
    MyApp.Repo,
    Commanded.Scheduler.Repo
  ]

config :my_app, Commanded.Scheduler.Repo,
  migration_source: "scheduler_schema_migrations"

You must set the migration_source for the scheduler repo to a different table name from Ecto's default (schema_migrations) as shown above. This ensures that migrations for your own application's Ecto repo do not interfere with the Scheduler migrations when running mix ecto.migrate.

Then using Ecto's mix tasks will include the Commanded scheduler repository at the same time as your own app's:

mix do ecto.create, ecto.migrate

To handle migrations in production (since mix is not accessible in a release) then you will need to add this as a release task.

def migrate_database() do
 Ecto.Migrator.with_repo(Commanded.Scheduler.Repo, fn repo ->
   path = Ecto.Migrator.migrations_path(repo)
   Ecto.Migrator.run(repo, path, :up, [all: true])
 end)
end