{"record":{"id":"76e320eafa42fb3b","repo":"apache/beam","slug":"error-publishing-message-v","errorCode":null,"errorMessage":"error publishing message: %v","messagePattern":"error publishing message: (.+?)","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"sdks/go/pkg/beam/io/natsio/write.go","lineNumber":101,"sourceCode":"func (fn *writeFn) ProcessElement(\n\tctx context.Context,\n\telem ProducerMessage,\n\temit func(PublishAck),\n) error {\n\tmsg := &nats.Msg{\n\t\tSubject: elem.Subject,\n\t\tData:    elem.Data,\n\t\tHeader:  elem.Headers,\n\t}\n\n\tvar opts []jetstream.PublishOpt\n\tif elem.ID != \"\" {\n\t\topts = append(opts, jetstream.WithMsgID(elem.ID))\n\t}\n\n\tack, err := fn.js.PublishMsg(ctx, msg, opts...)\n\tif err != nil {\n\t\treturn fmt.Errorf(\"error publishing message: %v\", err)\n\t}\n\n\tpubAck := PublishAck{\n\t\tStream:    ack.Stream,\n\t\tSubject:   elem.Subject,\n\t\tID:        elem.ID,\n\t\tSequence:  ack.Sequence,\n\t\tDuplicate: ack.Duplicate,\n\t}\n\temit(pubAck)\n\n\treturn nil\n}\n","sourceCodeStart":83,"sourceCodeEnd":115,"githubUrl":"https://github.com/apache/beam/blob/12126d8942aaf848030c478b4c6a28c6af861c66/sdks/go/pkg/beam/io/natsio/write.go#L83-L115","documentation":"This error is returned by natsio's writer DoFn (ProcessElement) when jetstream.Js.PublishMsg fails to publish a message to a NATS JetStream subject. The NATS client returns an error (connection issues, subject problems, stream limits, etc.) and the DoFn wraps it with context so the pipeline element fails with a readable message. The original NATS error is included via %v.","triggerScenarios":"Calling beam.Par with the natsio.Write transform when the underlying jetstream PublishMsg call fails: NATS server unreachable, subject has no stream binding, JetStream publish timeouts, max payload exceeded, or stream limits (max msgs/bytes) reached.","commonSituations":"NATS server restarted or down mid-pipeline; publishing to a subject not covered by any JetStream stream; message larger than max_payload; exceeding stream retention/storage limits; using a JetStream-enabled write against a core-NATS-only server.","solutions":["Verify NATS server connectivity and that the configured JetStream stream covers the target subject (nats stream info / add stream).","Check the wrapped %v cause: for max payload errors, reduce message size or raise server max_payload; for timeouts, increase publish timeout or check network.","Ensure the server has JetStream enabled (store_dir configured, --js flag on nats-server) if running a self-hosted server.","Add a dead-letter/retry pattern (e.g. a Sofa/beam combinator) so transient publish failures don't fail the whole bundle.","Confirm credentials/account limits allow publishing at the pipeline's throughput."],"exampleFix":"// before: publishing to subject with no JetStream stream bound\njs.PublishMsg(ctx, msg)\n// error: error publishing message: nats: no responders available for request\n\n// after: create/bind a stream for the subject first\n// nats stream add ORDERS --subjects \"orders.>\"\n// or via Go:\n_, err := js.CreateStream(ctx, jetstream.StreamConfig{Name: \"ORDERS\", Subjects: []string{\"orders.>\"}})","handlingStrategy":"validation","validationCode":"// Before running the pipeline, verify JetStream connectivity and stream coverage for the subject:\nconn, err := nats.Connect(url)\nif err != nil { return err }\njs, _ := jetstream.New(conn)\nif _, err := js.StreamNameForSubject(ctx, subject); err != nil {\n    return fmt.Errorf(\"no stream bound to subject %s: %w\", subject, err)\n}","typeGuard":null,"tryCatchPattern":null,"preventionTips":["Bind every publish subject to a JetStream stream before launching the pipeline.","Monitor publish latency/errors in the NATS dashboard and alert on 'no responders' or slow consumers.","Keep message payloads under the server max_payload and enforce size checks at pipeline input.","Use natsio.Write only against JetStream-enabled servers."],"tags":["nats","jetstream","publish-failure","network","go"],"backgroundTag":"api-error-response","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"}