{"record":{"id":"3cb7dc6b5f0e5442","repo":"vxcontrol/pentagi","slug":"failed-to-create-flow-msg-log-w","errorCode":null,"errorMessage":"failed to create flow msg log: %w","messagePattern":"failed to create flow msg log: %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"backend/pkg/controller/flow.go","lineNumber":1174,"sourceCode":"\t}\n\n\treturn nil\n}\n\nfunc newFlowProviderWorkers(\n\tctx context.Context,\n\tflowID int64,\n\tcnts *flowProviderControllers,\n\tpub subscriptions.FlowPublisher,\n) (*flowProviderWorkers, error) {\n\talw, err := cnts.alc.NewFlowAgentLog(ctx, flowID, pub)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to create flow agent log: %w\", err)\n\t}\n\n\tmlw, err := cnts.mlc.NewFlowMsgLog(ctx, flowID, pub)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to create flow msg log: %w\", err)\n\t}\n\n\tslw, err := cnts.slc.NewFlowSearchLog(ctx, flowID, pub)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to create flow search log: %w\", err)\n\t}\n\n\ttlw, err := cnts.tlc.NewFlowTermLog(ctx, flowID, pub)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to create flow term log: %w\", err)\n\t}\n\n\tvslw, err := cnts.vslc.NewFlowVectorStoreLog(ctx, flowID, pub)\n\tif err != nil {\n\t\treturn nil, fmt.Errorf(\"failed to create flow vector store log: %w\", err)\n\t}\n\n\ttclw, err := cnts.tclc.NewFlowToolCallLog(ctx, flowID, pub)","sourceCodeStart":1156,"sourceCodeEnd":1192,"githubUrl":"https://github.com/vxcontrol/pentagi/blob/ea665308baaff015b226f308438a68d929d0f29b/backend/pkg/controller/flow.go#L1156-L1192","documentation":"Second step of newFlowProviderWorkers: the message log worker is created via cnts.mlc.NewFlowMsgLog(ctx, flowID, pub). A failure here is wrapped with this message and stops flow worker construction, meaning the flow cannot start without message logging persistence.","triggerScenarios":"NewFlowMsgLog fails during flow startup — DB error creating/accessing the message log storage for this flow, invalid flowID, or context cancellation after the agent log step succeeded.","commonSituations":"Postgres connection dropped between the agent-log and msg-log steps; flow was deleted concurrently; oversized/backlogged message_logs table causing timeouts; missing migration for the message log schema.","solutions":["Read the wrapped cause in backend logs to identify the failing SQL","Check PostgreSQL health and message_logs table status","Apply pending migrations and retry flow creation","Re-check that the flow row still exists (concurrent deletion)"],"exampleFix":"// before: sequential creation, partial failure leaves nothing behind\nmlw, err := cnts.mlc.NewFlowMsgLog(ctx, flowID, pub)\nif err != nil { return nil, fmt.Errorf(\"failed to create flow msg log: %w\", err) }\n// after: ensure ctx deadline so failures surface as timeouts, and log flowID\nctx, cancel := context.WithTimeout(ctx, 30*time.Second)\ndefer cancel()\nmlw, err := cnts.mlc.NewFlowMsgLog(ctx, flowID, pub)\nif err != nil {\n    return nil, fmt.Errorf(\"failed to create flow msg log (flow=%d): %w\", flowID, err)\n}","handlingStrategy":"retry","validationCode":"var exists int\nif err := db.QueryRowContext(ctx, `SELECT COUNT(1) FROM flows WHERE id=$1`, flowID).Scan(&exists); err != nil || exists == 0 {\n    return fmt.Errorf(\"flow %d missing before creating msg log\", flowID)\n}","typeGuard":"func hasValidFlowID(flowID int64) bool { return flowID > 0 }","tryCatchPattern":"mlw, err := cnts.mlc.NewFlowMsgLog(ctx, flowID, pub)\nif err != nil {\n    if errors.Is(err, context.Canceled) { return nil, err }\n    return nil, fmt.Errorf(\"failed to create flow msg log (flow=%d): %w\", flowID, err)\n}","preventionTips":["Run all goose migrations at startup","Check DB health between flow-creation steps in dashboards","Avoid long-running transactions that block message_logs","Handle context cancellation distinctly from DB errors"],"tags":["go","database","flow-startup","logging"],"backgroundTag":"database-write-failed","analyzedSha":"ea665308baaff015b226f308438a68d929d0f29b","analyzedAt":"2026-09-01T14:16:31.421Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-08T10:18:20.063Z"}