Convert packagename back to string on downgrade

nmdc_server/migrations/versions/afa1ff687968_convert_packagename_to_an_array.py

@@ -53,5 +53,28 @@ def upgrade():
 
 def downgrade():
     # ### commands auto generated by Alembic - please adjust! ###
-    pass
+    submission_metadata = table(
+        "submission_metadata",
+        column("id", sa.String),
+        column("metadata_submission", JSONB),
+        column("study_name", sa.String),
+        column("templates", JSONB),
+    )
+    connection = op.get_bind()
+    submissions = connection.execute(
+        sa.select([submission_metadata.c.id, submission_metadata.c.metadata_submission])
+    )
+    for submission in submissions:
+        metadata_submission = submission.metadata_submission
+        package_name = metadata_submission.get("packageName", None)
+        # The first element of this list would be the default env_package
+        if isinstance(package_name, list):
+            metadata_submission["packageName"] = package_name[0]
+
+        update_stmt = (
+            submission_metadata.update()
+            .where(submission_metadata.c.id == submission.id)
+            .values(metadata_submission=metadata_submission)
+        )
+        connection.execute(update_stmt)
     # ### end Alembic commands ###