{"record":{"id":"65ba2dfad55af871","repo":"apache/beam","slug":"an-unsupported-source-was-specified-s-please-specify-one-of","errorCode":null,"errorMessage":"An unsupported source was specified: '%s'. Please specify one of the following sources: %s","messagePattern":"An unsupported source was specified: '(.+?)'\\. Please specify one of the following sources: (.+?)","errorType":"validation","errorClass":"ValueError","httpStatus":null,"severity":"error","filePath":"sdks/python/apache_beam/transforms/managed.py","lineNumber":119,"sourceCode":"      KAFKA: ManagedTransforms.Urns.KAFKA_READ.urn,\n      BIGQUERY: ManagedTransforms.Urns.BIGQUERY_READ.urn,\n      POSTGRES: ManagedTransforms.Urns.POSTGRES_READ.urn,\n      MYSQL: ManagedTransforms.Urns.MYSQL_READ.urn,\n      SQL_SERVER: ManagedTransforms.Urns.SQL_SERVER_READ.urn,\n      DELTA: ManagedTransforms.Urns.DELTA_LAKE_READ.urn,\n  }\n\n  def __init__(\n      self,\n      source: str,\n      config: Optional[dict[str, Any]] = None,\n      config_url: Optional[str] = None,\n      expansion_service=None):\n    super().__init__()\n    self._source = source\n    identifier = self._READ_TRANSFORMS.get(source.lower())\n    if not identifier:\n      raise ValueError(\n          f\"An unsupported source was specified: '{source}'. Please specify \"\n          f\"one of the following sources: {list(self._READ_TRANSFORMS.keys())}\")\n\n    # Store parameters for deferred expansion service creation\n    self._identifier = identifier\n    self._provided_expansion_service = expansion_service\n    self._underlying_identifier = identifier\n    self._yaml_config = yaml.dump(config)\n    self._config_url = config_url\n\n  def expand(self, input):\n    # Create expansion service with access to pipeline options\n    expansion_service = _resolve_expansion_service(\n        self._source,\n        self._identifier,\n        self._provided_expansion_service,\n        pipeline_options=input.pipeline._options)\n","sourceCodeStart":101,"sourceCodeEnd":137,"githubUrl":"https://github.com/apache/beam/blob/12126d8942aaf848030c478b4c6a28c6af861c66/sdks/python/apache_beam/transforms/managed.py#L101-L137","documentation":"ManagedReadTransform looked up the given source identifier in its table of known managed read sources (Kafka, BigQuery, Postgres, MySQL, SQL Server, Delta Lake, etc.) and found no entry; the accepted source keys are listed in the message.","triggerScenarios":"Thrown at sdks/python/apache_beam/transforms/managed.py:119 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":["Use one of the supported source keys, e.g. 'kafka', 'bigquery', 'postgres', 'mysql', 'sql_server', 'delta'","Check spelling/case of the source key against the list in the error message"],"exampleFix":null,"handlingStrategy":"validation","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"12126d8942aaf848030c478b4c6a28c6af861c66","analyzedAt":"2026-09-13T01:50:10.254Z","contentChangedAt":"2026-09-13T01:50:10.254Z","schemaVersion":2},"datasetVersion":"2026-09-20T03:17:13.778Z"}