Fix race condition causing events to be lost during initialization#1090
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bytesoverflow wants to merge 1 commit intosegmentio:masterfrom
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Fix race condition causing events to be lost during initialization#1090bytesoverflow wants to merge 1 commit intosegmentio:masterfrom
bytesoverflow wants to merge 1 commit intosegmentio:masterfrom
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…re onReady Fixed a race condition where events tracked during the onReady() processing were incorrectly categorized as pending and never sent to Segment. The bug occurred when: 1. App starts tracking events before initialization 2. During init, onReady() begins processing pending events (takes seconds) 3. New events arrive while onReady() is still running 4. These events check isReady (still false) and get saved as "pending" 5. Since onReady() already ran, these new pending events are never processed The fix simply swaps two lines to set isReady=true BEFORE calling onReady(), ensuring any events that arrive during processing go directly to the queue. Added tests to verify the initialization order and prevent regression.
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fixed in v2.21.4 |
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This PR fixes a critical race condition that causes events to be lost when they are tracked while the Segment client is processing pending events during initialization.
Problem
Events tracked during the app startup phase were being lost. When the Segment client initializes, it processes any events that were tracked before it was ready (pending events).
However, due to a race condition, new events arriving during this processing period were incorrectly saved as "pending" and never sent.
Reproduction Steps
Root Cause
The
isReadyflag was being set AFTER theonReady()function completed processing pending events. This created a window where:isReady.valueisReady.valueis stillfalse, they get saved as pendingSolution
Set the
isReadyflag totrueBEFORE processing pending events, not after. This ensures any events arriving during initialization go directly to the queue.