{"record":{"id":"7638ae336e7f96f8","repo":"vxcontrol/pentagi","slug":"failed-to-create-flow-agent-log-w","errorCode":null,"errorMessage":"failed to create flow agent log: %w","messagePattern":"failed to create flow agent log: %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"backend/pkg/controller/flow.go","lineNumber":1169,"sourceCode":"\t} else {\n\t\tspan.End(\n\t\t\tlangfuse.WithSpanOutput(result),\n\t\t\tlangfuse.WithSpanStatus(\"success\"),\n\t\t)\n\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)","sourceCodeStart":1151,"sourceCodeEnd":1187,"githubUrl":"https://github.com/vxcontrol/pentagi/blob/ea665308baaff015b226f308438a68d929d0f29b/backend/pkg/controller/flow.go#L1151-L1187","documentation":"newFlowProviderWorkers builds the per-flow log worker set when a flow starts. Its first step creates the agent log worker via cnts.alc.NewFlowAgentLog(ctx, flowID, pub); any error is wrapped with this message and aborts flow worker construction, so the flow fails to start rather than run without agent event logging.","triggerScenarios":"Creating a new flow (or restoring its workers) calls newFlowProviderWorkers and NewFlowAgentLog fails — usually a database error inserting/initializing the agent log, or the flow ID is invalid/nonexistent.","commonSituations":"PostgreSQL down or connection pool exhausted at flow creation time; flow row not yet committed when workers are created; concurrent flow deletion; DB schema out of date (missing migration).","solutions":["Check the wrapped error and Postgres logs for the underlying failure","Run pending goose migrations so the agent-log schema is current","Verify DB connectivity/pool settings, then retry flow creation","Confirm the flow ID exists in the flows table before creating workers"],"exampleFix":"// before: create workers with no DB health check\nworkers, err := newFlowProviderWorkers(ctx, flowID, cnts, pub)\n// after: precondition the DB and pass a fresh context with deadline\nif err := db.PingContext(ctx); err != nil {\n    return nil, fmt.Errorf(\"db unavailable before flow start: %w\", err)\n}\nctx, cancel := context.WithTimeout(ctx, 30*time.Second)\ndefer cancel()\nworkers, err := newFlowProviderWorkers(ctx, flowID, cnts, pub)","handlingStrategy":"retry","validationCode":"if err := db.PingContext(ctx); err != nil {\n    return fmt.Errorf(\"db unavailable, cannot start flow: %w\", err)\n}","typeGuard":"func hasValidFlowID(flowID int64) bool { return flowID > 0 }","tryCatchPattern":"alw, err := cnts.alc.NewFlowAgentLog(ctx, flowID, pub)\nif err != nil {\n    if isTransientDBError(err) { /* retry up to 3x with backoff */ }\n    return nil, fmt.Errorf(\"failed to create flow agent log (flow=%d): %w\", flowID, err)\n}","preventionTips":["Ping the DB and run migrations before starting flows","Use a context with a deadline for worker creation","Serialize flow starts to avoid pool exhaustion","Verify the flow row is committed before creating workers"],"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"}