Split CreateFollowingRelationships to multiple migrations

priv/repo/migrations/20191007073319_create_following_relationships.exs

@@ -3,8 +3,6 @@ defmodule Pleroma.Repo.Migrations.CreateFollowingRelationships do
 
   # had to disable these to be able to restore `following` index concurrently
   # https://hexdocs.pm/ecto_sql/Ecto.Migration.html#index/3-adding-dropping-indexes-concurrently
-  @disable_ddl_transaction true
-  @disable_migration_lock true
 
   def change do
     create_if_not_exists table(:following_relationships) do
@@ -17,95 +15,5 @@ def change do
 
     create_if_not_exists(index(:following_relationships, :follower_id))
     create_if_not_exists(unique_index(:following_relationships, [:follower_id, :following_id]))
-
-    execute(import_following_from_users(), "")
-    execute(import_following_from_activities(), restore_following_column())
-
-    drop(index(:users, [:following], concurrently: true, using: :gin))
-
-    alter table(:users) do
-      remove(:following, {:array, :string}, default: [])
-    end
-  end
-
-  defp import_following_from_users do
-    """
-    INSERT INTO following_relationships (follower_id, following_id, state, inserted_at, updated_at)
-    SELECT
-        relations.follower_id,
-        following.id,
-        'accept',
-        now(),
-        now()
-    FROM (
-        SELECT
-            users.id AS follower_id,
-            unnest(users.following) AS following_ap_id
-        FROM
-            users
-        WHERE
-            users.following != '{}'
-            AND users.local = false OR users.local = true AND users.email IS NOT NULL -- Exclude `internal/fetch` and `relay`
-    ) AS relations
-        JOIN users AS "following" ON "following".follower_address = relations.following_ap_id
-
-        WHERE relations.follower_id != following.id
-    ON CONFLICT DO NOTHING
-    """
-  end
-
-  defp import_following_from_activities do
-    """
-    INSERT INTO
-        following_relationships (
-            follower_id,
-            following_id,
-            state,
-            inserted_at,
-            updated_at
-        )
-    SELECT
-        followers.id,
-        following.id,
-        activities.data ->> 'state',
-        (activities.data ->> 'published') :: timestamp,
-        now()
-    FROM
-        activities
-        JOIN users AS followers ON (activities.actor = followers.ap_id)
-        JOIN users AS following ON (activities.data ->> 'object' = following.ap_id)
-    WHERE
-        activities.data ->> 'type' = 'Follow'
-        AND activities.data ->> 'state' IN ('accept', 'pending', 'reject')
-    ORDER BY activities.updated_at DESC
-    ON CONFLICT DO NOTHING
-    """
-  end
-
-  defp restore_following_column do
-    """
-    UPDATE
-        users
-    SET
-        following = following_query.following_array,
-        updated_at = now()
-    FROM (
-        SELECT
-            follwer.id AS follower_id,
-            CASE follwer.local
-            WHEN TRUE THEN
-                array_prepend(follwer.follower_address, array_agg(following.follower_address))
-            ELSE
-                array_agg(following.follower_address)
-            END AS following_array
-        FROM
-            following_relationships
-            JOIN users AS follwer ON follwer.id = following_relationships.follower_id
-            JOIN users AS FOLLOWING ON following.id = following_relationships.following_id
-        GROUP BY
-            follwer.id) AS following_query
-    WHERE
-        following_query.follower_id = users.id
-    """
   end
 end

priv/repo/migrations/20191008132217_migrate_following_relationships.exs

@@ -0,0 +1,89 @@
+defmodule Pleroma.Repo.Migrations.MigrateFollowingRelationships do
+  use Ecto.Migration
+
+  def change do
+    execute(import_following_from_users(), "")
+    execute(import_following_from_activities(), restore_following_column())
+  end
+
+  defp import_following_from_users do
+    """
+    INSERT INTO following_relationships (follower_id, following_id, state, inserted_at, updated_at)
+    SELECT
+        relations.follower_id,
+        following.id,
+        'accept',
+        now(),
+        now()
+    FROM (
+        SELECT
+            users.id AS follower_id,
+            unnest(users.following) AS following_ap_id
+        FROM
+            users
+        WHERE
+            users.following != '{}'
+            AND users.local = false OR users.local = true AND users.email IS NOT NULL -- Exclude `internal/fetch` and `relay`
+    ) AS relations
+        JOIN users AS "following" ON "following".follower_address = relations.following_ap_id
+
+        WHERE relations.follower_id != following.id
+    ON CONFLICT DO NOTHING
+    """
+  end
+
+  defp import_following_from_activities do
+    """
+    INSERT INTO
+        following_relationships (
+            follower_id,
+            following_id,
+            state,
+            inserted_at,
+            updated_at
+        )
+    SELECT
+        followers.id,
+        following.id,
+        activities.data ->> 'state',
+        (activities.data ->> 'published') :: timestamp,
+        now()
+    FROM
+        activities
+        JOIN users AS followers ON (activities.actor = followers.ap_id)
+        JOIN users AS following ON (activities.data ->> 'object' = following.ap_id)
+    WHERE
+        activities.data ->> 'type' = 'Follow'
+        AND activities.data ->> 'state' IN ('accept', 'pending', 'reject')
+    ORDER BY activities.updated_at DESC
+    ON CONFLICT DO NOTHING
+    """
+  end
+
+  defp restore_following_column do
+    """
+    UPDATE
+        users
+    SET
+        following = following_query.following_array,
+        updated_at = now()
+    FROM (
+        SELECT
+            follwer.id AS follower_id,
+            CASE follwer.local
+            WHEN TRUE THEN
+                array_prepend(follwer.follower_address, array_agg(following.follower_address))
+            ELSE
+                array_agg(following.follower_address)
+            END AS following_array
+        FROM
+            following_relationships
+            JOIN users AS follwer ON follwer.id = following_relationships.follower_id
+            JOIN users AS FOLLOWING ON following.id = following_relationships.following_id
+        GROUP BY
+            follwer.id) AS following_query
+    WHERE
+        following_query.follower_id = users.id
+    """
+  end
+end

priv/repo/migrations/20191008132427_drop_users_following.exs

@@ -0,0 +1,14 @@
+defmodule Pleroma.Repo.Migrations.DropUsersFollowing do
+  use Ecto.Migration
+
+  @disable_ddl_transaction true
+  @disable_migration_lock true
+
+  def change do
+    drop(index(:users, [:following], concurrently: true, using: :gin))
+
+    alter table(:users) do
+      remove(:following, {:array, :string}, default: [])
+    end
+  end
+end