fix(amplitude-session): recover lastEventTime on partial persist#1198
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fix(amplitude-session): recover lastEventTime on partial persist#1198
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… Fetch iOS Background Fetch can briefly trigger AppState 'active' without user interaction, causing rapid session creation/destruction cycles. Add a 1-second timestamp guard in onForeground() to prevent new sessions from starting within 1 second of the last session creation. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Replace incorrect 1-second timestamp guard with proper root cause fix. The 0-second session bug is caused by non-atomic AsyncStorage persistence: when the app is killed (e.g. during iOS Background Fetch), sessionId may persist while lastEventTime does not. On relaunch, lastEventTime === -1 with a valid sessionId falsely triggers session expiration, ending the just-created session immediately. The fix recovers lastEventTime from sessionId when partial persistence is detected, preventing the false expiration. Also adds hypothesis-driven reproduction tests that verify the fix. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
Fixes 0-second sessions in the Amplitude Session plugin on iOS when Background Fetch is enabled.
Root cause: The plugin persists
sessionId,lastEventTime, andeventSessionIdto AsyncStorage via independent fire-and-forget writes in property setters. If the app is killed before all writes complete (common during iOS Background Fetch),sessionIdmay persist whilelastEventTimedoes not. On the next launch,lastEventTime === -1with a validsessionIdfalsely triggers session expiration, ending the just-created session immediately — producing a 0-second session.Fix: When
lastEventTime === -1butsessionId >= 0(indicating partial persistence), recoverlastEventTimefromsessionIdinstead of treating the session as expired. Also removes the incorrect 1-second timestamp guard fromonForeground()that was based on a disproven hypothesis.Changes
startNewSessionIfNecessary(): Add recovery logic for partial AsyncStorage persistencestartNewSessionIfNecessary(): RemovelastEventTime === -1fromisSessionExpired(now handled by recovery)onForeground(): Remove incorrect 1-second timestamp guardTest plan
lastEventTimerecovery fromsessionId🤖 Generated with Claude Code