Jun 24 - Implement devices tracker - Phase32 migration script fix

migrations/versions/phase32_device_token_columns.py

@@ -1,40 +1,66 @@
 """phase32 — add ios_version and last_seen_at to api_device_tokens
 
-phase31 recorded as applied but the ALTER statements never ran because
+phase31 recorded as applied but ALTER statements never executed.
-the migration used op.get_bind() pattern that failed silently.
+Uses INFORMATION_SCHEMA column-existence checks — safe on MySQL 5.7+.
-This migration adds the two columns using raw SQL with IF NOT EXISTS
-(same pattern as all working migrations in this project).
 Also drops the orphaned device_registrations table from phase30 if present.
 """
 
-from alembic import op
-
 revision      = 'phase32_device_token_columns'
 down_revision = 'phase31_device_registry'
 branch_labels = None
 depends_on    = None
 
+from alembic import op
+import sqlalchemy as sa
+
+
+def _column_exists(conn, table, column):
+    result = conn.execute(sa.text(
+        "SELECT COUNT(*) FROM INFORMATION_SCHEMA.COLUMNS "
+        "WHERE TABLE_SCHEMA = DATABASE() "
+        "AND TABLE_NAME = :t AND COLUMN_NAME = :c"
+    ), {"t": table, "c": column})
+    return result.scalar() > 0
+
+
+def _table_exists(conn, table):
+    result = conn.execute(sa.text(
+        "SELECT COUNT(*) FROM INFORMATION_SCHEMA.TABLES "
+        "WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = :t"
+    ), {"t": table})
+    return result.scalar() > 0
+
 
 def upgrade():
-    op.execute("""
+    bind = op.get_bind()
-        ALTER TABLE api_device_tokens
-        ADD COLUMN IF NOT EXISTS ios_version VARCHAR(20) NULL
-    """)
 
-    op.execute("""
+    if not _column_exists(bind, 'api_device_tokens', 'ios_version'):
-        ALTER TABLE api_device_tokens
+        op.execute(sa.text(
-        ADD COLUMN IF NOT EXISTS last_seen_at DATETIME NULL
+            "ALTER TABLE api_device_tokens ADD COLUMN ios_version VARCHAR(20) NULL"
-    """)
+        ))
 
-    op.execute("""
+    if not _column_exists(bind, 'api_device_tokens', 'last_seen_at'):
-        UPDATE api_device_tokens
+        op.execute(sa.text(
-        SET last_seen_at = registered_at
+            "ALTER TABLE api_device_tokens ADD COLUMN last_seen_at DATETIME NULL"
-        WHERE last_seen_at IS NULL
+        ))
-    """)
 
-    op.execute("DROP TABLE IF EXISTS device_registrations")
+    op.execute(sa.text(
+        "UPDATE api_device_tokens SET last_seen_at = registered_at WHERE last_seen_at IS NULL"
+    ))
+
+    if _table_exists(bind, 'device_registrations'):
+        op.execute(sa.text("DROP TABLE device_registrations"))
 
 
 def downgrade():
-    op.execute("ALTER TABLE api_device_tokens DROP COLUMN IF EXISTS ios_version")
+    bind = op.get_bind()
-    op.execute("ALTER TABLE api_device_tokens DROP COLUMN IF EXISTS last_seen_at")
+
+    if _column_exists(bind, 'api_device_tokens', 'ios_version'):
+        op.execute(sa.text(
+            "ALTER TABLE api_device_tokens DROP COLUMN ios_version"
+        ))
+
+    if _column_exists(bind, 'api_device_tokens', 'last_seen_at'):
+        op.execute(sa.text(
+            "ALTER TABLE api_device_tokens DROP COLUMN last_seen_at"
+        ))