{"record":{"id":"a258e46af978e9bc","repo":"gofiber/fiber","slug":"failed-to-reset-session-w","errorCode":null,"errorMessage":"failed to reset session: %w","messagePattern":"failed to reset session: %w","errorType":"exception","errorClass":null,"httpStatus":null,"severity":"error","filePath":"middleware/session/store.go","lineNumber":189,"sourceCode":"\t// Decode session data if found\n\tif rawData != nil {\n\t\tsess.data.Lock()\n\t\terr := sess.decodeSessionData(rawData)\n\t\tsess.data.Unlock()\n\t\tif err != nil {\n\t\t\tsess.mu.Unlock()\n\t\t\tsess.Release()\n\t\t\treturn nil, fmt.Errorf(\"failed to decode session data: %w\", err)\n\t\t}\n\t}\n\n\tsess.mu.Unlock()\n\n\tif isFresh && s.AbsoluteTimeout > 0 {\n\t\tsess.setAbsExpiration(time.Now().Add(s.AbsoluteTimeout))\n\t} else if sess.isAbsExpired() {\n\t\tif err := sess.Reset(); err != nil {\n\t\t\treturn nil, fmt.Errorf(\"failed to reset session: %w\", err)\n\t\t}\n\t\tsess.setAbsExpiration(time.Now().Add(s.AbsoluteTimeout))\n\t}\n\n\treturn sess, nil\n}\n\n// getSessionID returns the session ID using the configured extractor.\n// The extractor is provided by the shared extractors package.\n//\n// Parameters:\n//   - c: The Fiber context.\n//\n// Returns:\n//   - string: The session ID.\n//\n// Usage:\n//","sourceCodeStart":171,"sourceCodeEnd":207,"githubUrl":"https://github.com/gofiber/fiber/blob/a105acad6c1e4576a77f01e02973f67e962bb58d/middleware/session/store.go#L171-L207","documentation":"Thrown when an absolutely-expired session is being acquired and Reset() fails. ResetWithContext deletes the old session ID from Storage (Storage.DeleteWithContext) and then refreshes local state; the %w wraps the storage delete error. A failure here means the Storage backend rejected the delete, not a data-format problem.","triggerScenarios":"AbsoluteTimeout is configured (>0), the loaded session is past its absolute expiration, and Storage.DeleteWithContext(ctx, s.id) returns an error — backend connectivity loss, permission denial, timeout, or a buggy custom Storage implementation.","commonSituations":"Transient Redis/DB outage at the moment a long-lived session expires; network partition to the session store; custom Storage whose Delete returns an error on missing key; context cancellation during expiry handling.","solutions":["Check Storage backend health and connectivity (Redis ping, DB reachability).","Retry on transient errors with backoff; treat permanent errors as a storage implementation bug.","If using a custom Storage, ensure Delete/DeleteWithContext returns nil for a missing key.","Make sure the passed context has a generous enough deadline for the delete."],"exampleFix":"// before: Reset fails because Redis is briefly unreachable\n// after: retry the acquisition once the backend recovers\nfor i := 0; i < 3; i++ {\n    sess, err = store.Get(c)\n    if err == nil { break }\n    time.Sleep(backoff(i))\n}","handlingStrategy":"retry","validationCode":"// Confirm the storage backend is reachable before relying on Reset.\nfunc storageHealthy(s Storage) bool {\n    type pinger interface { Ping(context.Context) error }\n    if p, ok := s.(pinger); ok {\n        return p.Ping(context.Background()) == nil\n    }\n    return true\n}","typeGuard":null,"tryCatchPattern":"var sess *Session\nfor attempt := 0; attempt < 3; attempt++ {\n    var err error\n    sess, err = store.Get(c)\n    if err == nil { break }\n    if !errors.Is(err, /* transient storage sentinel */) && attempt < 2 {\n        time.Sleep(time.Duration(attempt+1) * 100 * time.Millisecond)\n        continue\n    }\n    return err\n}","preventionTips":["Ensure your Storage implementation's Delete returns nil for missing keys (idempotent).","Monitor storage latency/errors; absolute-expiry storms can spike delete load.","Give the request context a deadline long enough for the delete.","For custom Storage, unit-test Delete on missing keys."],"tags":["session","storage","delete","absolute-timeout"],"backgroundTag":null,"analyzedSha":"a105acad6c1e4576a77f01e02973f67e962bb58d","analyzedAt":"2026-08-11T17:33:26.942Z","contentChangedAt":null,"schemaVersion":2},"datasetVersion":"2026-09-23T08:17:48.524Z"}