From 1b076bce1e2f7192fa7468ebc6a2e9dae142fd25 Mon Sep 17 00:00:00 2001
From: Igor Ilic <30923996+dexters1@users.noreply.github.com>
Date: Thu, 14 Aug 2025 21:50:36 +0200
Subject: [PATCH] Loader separation migration (#1251)

<!-- .github/pull_request_template.md -->

## Description
<!-- Provide a clear description of the changes in this PR -->

## DCO Affirmation
I affirm that all code in every commit of this pull request conforms to
the terms of the Topoteretes Developer Certificate of Origin.
---
 .../9e7a3cb85175_loader_separation.py         | 104 ++++++++++++++++++
 1 file changed, 104 insertions(+)
 create mode 100644 alembic/versions/9e7a3cb85175_loader_separation.py

diff --git a/alembic/versions/9e7a3cb85175_loader_separation.py b/alembic/versions/9e7a3cb85175_loader_separation.py
new file mode 100644
index 000000000..6e5497b9f
--- /dev/null
+++ b/alembic/versions/9e7a3cb85175_loader_separation.py
@@ -0,0 +1,104 @@
+"""loader_separation
+
+Revision ID: 9e7a3cb85175
+Revises: 1daae0df1866
+Create Date: 2025-08-14 19:18:11.406907
+
+"""
+
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision: str = "9e7a3cb85175"
+down_revision: Union[str, None] = "1daae0df1866"
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def _get_column(inspector, table, name, schema=None):
+    for col in inspector.get_columns(table, schema=schema):
+        if col["name"] == name:
+            return col
+    return None
+
+
+def upgrade() -> None:
+    conn = op.get_bind()
+    insp = sa.inspect(conn)
+
+    # Define table with all necessary columns including primary key
+    data = sa.table(
+        "data",
+        sa.Column("id", sa.UUID, primary_key=True),  # Critical for SQLite
+        sa.Column("original_extension", sa.String()),
+        sa.Column("original_mime_type", sa.String()),
+        sa.Column("original_data_location", sa.String()),
+        sa.Column("extension", sa.String()),
+        sa.Column("mime_type", sa.String()),
+        sa.Column("raw_data_location", sa.String()),
+    )
+
+    original_extension_column = _get_column(insp, "data", "original_extension")
+    if not original_extension_column:
+        op.add_column("data", sa.Column("original_extension", sa.String(), nullable=True))
+        if op.get_context().dialect.name == "sqlite":
+            # If column doesn't exist create new original_extension column and update from values of extension column
+            with op.batch_alter_table("data") as batch_op:
+                batch_op.execute(
+                    data.update().values(
+                        original_extension=data.c.extension,
+                    )
+                )
+        else:
+            conn = op.get_bind()
+            conn.execute(data.update().values(original_extension=data.c.extension))
+
+    original_mime_type = _get_column(insp, "data", "original_mime_type")
+    if not original_mime_type:
+        # If column doesn't exist create new original_mime_type column and update from values of mime_type column
+        op.add_column("data", sa.Column("original_mime_type", sa.String(), nullable=True))
+        if op.get_context().dialect.name == "sqlite":
+            with op.batch_alter_table("data") as batch_op:
+                batch_op.execute(
+                    data.update().values(
+                        original_mime_type=data.c.mime_type,
+                    )
+                )
+        else:
+            conn = op.get_bind()
+            conn.execute(data.update().values(original_mime_type=data.c.mime_type))
+
+    loader_engine = _get_column(insp, "data", "loader_engine")
+    if not loader_engine:
+        op.add_column("data", sa.Column("loader_engine", sa.String(), nullable=True))
+
+    original_data_location = _get_column(insp, "data", "original_data_location")
+    if not original_data_location:
+        # If column doesn't exist create new original data column and update from values of raw_data_location column
+        op.add_column("data", sa.Column("original_data_location", sa.String(), nullable=True))
+        if op.get_context().dialect.name == "sqlite":
+            with op.batch_alter_table("data") as batch_op:
+                batch_op.execute(
+                    data.update().values(
+                        original_data_location=data.c.raw_data_location,
+                    )
+                )
+        else:
+            conn = op.get_bind()
+            conn.execute(data.update().values(original_data_location=data.c.raw_data_location))
+
+    raw_content_hash = _get_column(insp, "data", "raw_content_hash")
+    if not raw_content_hash:
+        op.add_column("data", sa.Column("raw_content_hash", sa.String(), nullable=True))
+
+
+def downgrade() -> None:
+    op.drop_column("data", "raw_content_hash")
+    op.drop_column("data", "original_data_location")
+    op.drop_column("data", "loader_engine")
+    op.drop_column("data", "original_mime_type")
+    op.drop_column("data", "original_extension")