build(phoenix): use sqlite instead of postgres

lib/learning_phoenix/application.ex

@@ -10,6 +10,8 @@ defmodule LearningPhoenix.Application do
     children = [
       LearningPhoenixWeb.Telemetry,
       LearningPhoenix.Repo,
+      {Ecto.Migrator,
+       repos: Application.fetch_env!(:learning_phoenix, :ecto_repos), skip: skip_migrations?()},
       {DNSCluster, query: Application.get_env(:learning_phoenix, :dns_cluster_query) || :ignore},
       {Phoenix.PubSub, name: LearningPhoenix.PubSub},
       # Start a worker by calling: LearningPhoenix.Worker.start_link(arg)
@@ -31,4 +33,9 @@ defmodule LearningPhoenix.Application do
     LearningPhoenixWeb.Endpoint.config_change(changed, removed)
     :ok
   end
+
+  defp skip_migrations?() do
+    # By default, sqlite migrations are run when using a release
+    System.get_env("RELEASE_NAME") == nil
+  end
 end

lib/learning_phoenix/repo.ex

@@ -1,5 +1,5 @@
 defmodule LearningPhoenix.Repo do
   use Ecto.Repo,
     otp_app: :learning_phoenix,
-    adapter: Ecto.Adapters.Postgres
+    adapter: Ecto.Adapters.SQLite3
 end

lib/learning_phoenix_web/endpoint.ex

@@ -7,7 +7,7 @@ defmodule LearningPhoenixWeb.Endpoint do
   @session_options [
     store: :cookie,
     key: "_learning_phoenix_key",
-    signing_salt: "RuSasXTJ",
+    signing_salt: "FPy3oQ90",
     same_site: "Lax"
   ]