feat(backend): storage trash with seven day retention, trashed files are not fetched again automatically

backend/migrations/versions/c9e2a7f4b1d8_media_trash.py

@@ -0,0 +1,57 @@
+"""media trash
+
+Revision ID: c9e2a7f4b1d8
+Revises: b6d1f4a82e57
+Create Date: 2026-10-14 03:00:00.000000
+
+"""
+
+from collections.abc import Sequence
+
+from alembic import op
+
+revision: str = "c9e2a7f4b1d8"
+down_revision: str | None = "b6d1f4a82e57"
+branch_labels: str | Sequence[str] | None = None
+depends_on: str | Sequence[str] | None = None
+
+_TRASH = """
+CREATE TABLE media_trash (
+    storage_key text PRIMARY KEY,
+    account_id integer NOT NULL,
+    chat_id bigint NOT NULL,
+    message_id bigint NOT NULL,
+    kind text NOT NULL,
+    mime text,
+    file_name text NOT NULL,
+    file_size bigint,
+    trashed_at timestamptz NOT NULL DEFAULT now()
+)
+"""
+
+
+def upgrade() -> None:
+    op.execute(
+        "ALTER TABLE media ADD COLUMN evicted_at timestamptz, "
+        "ADD COLUMN evicted_key text"
+    )
+    op.execute(
+        "CREATE INDEX ix_media_evicted_unique ON media (unique_id) "
+        "WHERE evicted_at IS NOT NULL"
+    )
+    op.execute(
+        "CREATE INDEX ix_media_evicted_key ON media (evicted_key) "
+        "WHERE evicted_key IS NOT NULL"
+    )
+    op.execute(_TRASH)
+    op.execute(
+        "CREATE INDEX ix_media_trash_account ON media_trash "
+        "(account_id, trashed_at DESC)"
+    )
+
+
+def downgrade() -> None:
+    op.execute("DROP TABLE IF EXISTS media_trash")
+    op.execute("DROP INDEX IF EXISTS ix_media_evicted_key")
+    op.execute("DROP INDEX IF EXISTS ix_media_evicted_unique")
+    op.execute("ALTER TABLE media DROP COLUMN evicted_key, DROP COLUMN evicted_at")