{"record":{"id":"1cf626bc936a7050","repo":"langgenius/dify","slug":"the-uploaded-file-is-empty","errorCode":null,"errorMessage":"The uploaded file is empty","messagePattern":"The uploaded file is empty","errorType":"exception","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"api/controllers/console/app/annotation.py","lineNumber":494,"sourceCode":"        # check file type\n        if not file.filename or not file.filename.lower().endswith(\".csv\"):\n            raise ValueError(\"Invalid file type. Only CSV files are allowed\")\n\n        # Check file size before processing\n        file.stream.seek(0, 2)  # Seek to end of file\n        file_size = file.stream.tell()\n        file.stream.seek(0)  # Reset to beginning\n\n        max_size_bytes = dify_config.ANNOTATION_IMPORT_FILE_SIZE_LIMIT * 1024 * 1024\n        if file_size > max_size_bytes:\n            abort(\n                413,\n                f\"File size exceeds maximum limit of {dify_config.ANNOTATION_IMPORT_FILE_SIZE_LIMIT}MB. \"\n                f\"Please reduce the file size and try again.\",\n            )\n\n        if file_size == 0:\n            raise ValueError(\"The uploaded file is empty\")\n\n        return dump_response(\n            AnnotationBatchImportResponse,\n            AppAnnotationService.batch_import_app_annotations(str(app_id), file, session),\n        )\n\n\n@console_ns.route(\"/apps/<uuid:app_id>/annotations/batch-import-status/<uuid:job_id>\")\nclass AnnotationBatchImportStatusApi(Resource):\n    @console_ns.doc(\"get_batch_import_status\")\n    @console_ns.doc(description=\"Get status of batch import job\")\n    @console_ns.doc(params={\"app_id\": \"Application ID\", \"job_id\": \"Job ID\"})\n    @console_ns.response(\n        200, \"Job status retrieved successfully\", console_ns.models[AnnotationJobStatusDetailResponse.__name__]\n    )\n    @console_ns.response(403, \"Insufficient permissions\")\n    @setup_required\n    @login_required","sourceCodeStart":476,"sourceCodeEnd":512,"githubUrl":"https://github.com/langgenius/dify/blob/ef8544b173fd6cd7a8e71df2cab576e52bebbfbc/api/controllers/console/app/annotation.py#L476-L512","documentation":"Raised by AnnotationBatchImportApi.post after the size check, when file_size == 0 bytes. Like the file-type check this is a raw ValueError, surfaced as a 400 through Flask's default handler rather than Dify's structured envelope. It catches CSVs that passed the extension check but contain no data.","triggerScenarios":"Uploading a newly-created empty CSV file (just headers absent); a truncated upload where the connection dropped mid-transfer leaving a zero-byte temp file; a template file that was never populated; a symbolic link pointing to /dev/null.","commonSituations":"Automated export pipeline writes the file but the source query returns zero rows and the writer leaves the file empty; CI test fixture checked in as an empty file; FTP/SFTP transfer mode stripping all content.","solutions":["Open the CSV locally and confirm it contains at least a header row and data.","If using a script to generate the file, raise an error in the script when zero rows are produced so you never send an empty file.","Re-run the export and verify the file size on disk is > 0 before uploading.","Check the upload client for truncation (e.g., incorrect binary mode in transfer)."],"exampleFix":"# before\nwith open('annotations.csv', 'w') as f:  # accidentally creates empty file\n    pass\n\n# after\nimport os\nassert os.path.getsize('annotations.csv') > 0, 'CSV is empty; regenerate it'","handlingStrategy":"validation","validationCode":"function assertNonEmptyFile(file) {\n  if (file.size === 0) throw new Error('CSV file is empty');\n  return file;\n}","typeGuard":"const isNonEmptyFile = (file) => !!file && file.size > 0;","tryCatchPattern":"try { await fetch(url, { method: 'POST', body: form }); }\ncatch (e) { if (/empty/.test(e.message)) alert('The selected CSV has no content.'); }","preventionTips":["Check file.size > 0 in the UI before submit.","Validate export pipelines never emit zero-byte files.","Log file size at upload time for debugging."],"tags":["annotations","file-upload","csv","validation","console-api"],"backgroundTag":null,"analyzedSha":"ef8544b173fd6cd7a8e71df2cab576e52bebbfbc","analyzedAt":"2026-08-12T05:15:17.394Z","schemaVersion":2},"datasetVersion":"2026-08-12T13:17:24.610Z"}