dify - 💡(How to fix) Fix Title: [1.14.0] API file upload is broken, works fine in 1.13.0 [1 participants]

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Dify version

1.14.0

Cloud or Self Hosted

Self Hosted (Docker)

Steps to reproduce

1. Create a workflow with a file input field.
2. Upload a valid file and get the file_id.
3. Call POST /v1/workflows/run with valid inputs.
4. Always get 400: { "code": "invalid_param", "message": "Invalid upload file" }

✔️ Expected Behavior

The file upload API should work normally and return 200.

❌ Actual Behavior

When calling POST /v1/workflows/run with a valid file input, the API returns: Status: 400 Body: { "code": "invalid_param", "message": "Invalid upload file", "status": 400 }

My request body: { "inputs": { "shangchuan": { "transfer_method": "local_file", "upload_file_id": "e135c086-f517-49d6-aad3-dd951c815caf", "type": "document" }, "requirement": "总结" }, "response_mode": "blocking", "user": "rongjie" }

All file IDs are valid and uploaded via /v1/files/upload correctly. All parameter formats (object / string file ID) have been tested and all fail in 1.14.

Expected Behavior

The API should accept the file parameter and execute the workflow successfully, just like in Dify 1.13.