[#3213] Explicitly defined PKs in hashtags_objects and data_migration_failed_ids. Added "pleroma.database rollback" task to revert a single migration.

lib/mix/tasks/pleroma/database.ex

@@ -20,6 +20,30 @@ defmodule Mix.Tasks.Pleroma.Database do
   @shortdoc "A collection of database related tasks"
   @moduledoc File.read!("docs/administration/CLI_tasks/database.md")
 
+  # Rolls back a specific migration (leaving subsequent migrations applied)
+  # Based on https://stackoverflow.com/a/53825840
+  def run(["rollback", version]) do
+    start_pleroma()
+
+    version = String.to_integer(version)
+    re = ~r/^#{version}_.*\.exs/
+    path = Application.app_dir(:pleroma, Path.join(["priv", "repo", "migrations"]))
+
+    result =
+      with {:find, "" <> file} <- {:find, Enum.find(File.ls!(path), &String.match?(&1, re))},
+           {:compile, [{mod, _} | _]} <- {:compile, Code.compile_file(Path.join(path, file))},
+           {:rollback, :ok} <- {:rollback, Ecto.Migrator.down(Repo, version, mod)} do
+        {:ok, "Reversed migration: #{file}"}
+      else
+        {:find, _} -> {:error, "No migration found with version prefix: #{version}"}
+        {:compile, e} -> {:error, "Problem compiling migration module: #{inspect(e)}"}
+        {:rollback, e} -> {:error, "Problem reversing migration: #{inspect(e)}"}
+        e -> {:error, "Something unexpected happened: #{inspect(e)}"}
+      end
+
+    IO.inspect(result)
+  end
+
   def run(["remove_embedded_objects" | args]) do
     {options, [], []} =
       OptionParser.parse(

priv/repo/migrations/20201221203824_create_hashtags_objects.exs

@@ -3,8 +3,8 @@ defmodule Pleroma.Repo.Migrations.CreateHashtagsObjects do
 
   def change do
     create_if_not_exists table(:hashtags_objects, primary_key: false) do
-      add(:hashtag_id, references(:hashtags), null: false)
+      add(:hashtag_id, references(:hashtags), null: false, primary_key: true)
-      add(:object_id, references(:objects), null: false)
+      add(:object_id, references(:objects), null: false, primary_key: true)
     end
 
     create_if_not_exists(unique_index(:hashtags_objects, [:hashtag_id, :object_id]))

priv/repo/migrations/20210106183301_data_migration_create_populate_hashtags_table.exs

@@ -10,5 +10,7 @@ defmodule Pleroma.Repo.Migrations.DataMigrationCreatePopulateHashtagsTable do
     )
   end
 
-  def down, do: :ok
+  def down do
+    execute("DELETE FROM data_migrations WHERE name = 'populate_hashtags_table';")
+  end
 end

priv/repo/migrations/20210111172254_create_data_migration_failed_ids.exs

@@ -3,8 +3,8 @@ defmodule Pleroma.Repo.Migrations.CreateDataMigrationFailedIds do
 
   def change do
     create_if_not_exists table(:data_migration_failed_ids, primary_key: false) do
-      add(:data_migration_id, references(:data_migrations), null: false)
+      add(:data_migration_id, references(:data_migrations), null: false, primary_key: true)
-      add(:record_id, :bigint, null: false)
+      add(:record_id, :bigint, null: false, primary_key: true)
     end
 
     create_if_not_exists(