1 files changed, 89 insertions, 0 deletions
diff --git a/priv/repo/migrations/20191008132217_migrate_following_relationships.exs b/priv/repo/migrations/20191008132217_migrate_following_relationships.exs
new file mode 100644
index 000000000..9d5c2648f
--- /dev/null
+++ b/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
+            follower.id AS follower_id,
+            CASE follower.local
+            WHEN TRUE THEN
+                array_prepend(follower.follower_address, array_agg(following.follower_address))
+            ELSE
+                array_agg(following.follower_address)
+            END AS following_array
+        FROM
+            following_relationships
+            JOIN users AS follower ON follower.id = following_relationships.follower_id
+            JOIN users AS following ON following.id = following_relationships.following_id
+        GROUP BY
+            follower.id) AS following_query
+    WHERE
+        following_query.follower_id = users.id
+    """
+  end
+end