add touchless docker deploys

lib/cannery/application.ex

@@ -9,6 +9,7 @@ defmodule Cannery.Application do
     children = [
       # Start the Ecto repository
       Cannery.Repo,
+      Cannery.Repo.Migrator,
       # Start the Telemetry supervisor
       CanneryWeb.Telemetry,
       # Start the PubSub system

lib/cannery/release.ex

@@ -0,0 +1,20 @@
+defmodule Cannery.Release do
+  @app :cannery
+
+  def rollback(repo, version) do
+    load_app()
+    {:ok, _, _} = Ecto.Migrator.with_repo(repo, &Ecto.Migrator.run(&1, :down, to: version))
+  end
+
+  defp load_app do
+    Application.load(@app)
+  end
+
+  def migrate do
+    load_app()
+
+    for repo <- Application.fetch_env!(@app, :ecto_repos) do
+      {:ok, _, _} = Ecto.Migrator.with_repo(repo, &Ecto.Migrator.run(&1, :up, all: true))
+    end
+  end
+end

lib/cannery/repo/migrator.ex

@@ -0,0 +1,18 @@
+defmodule Cannery.Repo.Migrator do
+  use GenServer
+  require Logger
+  
+  def start_link(_) do
+    GenServer.start_link(__MODULE__, [], [])
+  end
+  
+  def init(_) do
+    migrate!()
+    {:ok, nil}
+  end
+  
+  def migrate! do
+    path = Application.app_dir(:cannery, "priv/repo/migrations")
+    Ecto.Migrator.run(Cannery.Repo, path, :up, all: true)
+  end
+end