fix: prevent double-activation of machine tokens via atomic CAS - #197
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gusye1234 wants to merge 2 commits into
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fix: prevent double-activation of machine tokens via atomic CAS#197gusye1234 wants to merge 2 commits into
gusye1234 wants to merge 2 commits into
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Adds status='pending' condition to the UPDATE WHERE clause so only one concurrent request can activate a token. Returns success/failure to the route handler which now returns 409 on conflict. Closes #150
The function now returns a boolean indicating success, so the test mock must return true for the happy-path tests.
gusye1234
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May 28, 2026
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Review — PR #197: prevent double-activation of machine tokens via atomic CAS
Solid fix for a TOCTOU race condition. The approach is textbook CAS:
- The WHERE clause now includes
eq(machineToken.status, "pending")— two concurrent activations can't both succeed because only the first UPDATE will match a row. .returning()+ boolean return makes the caller aware of whether activation actually happened.- 409 response for already-activated tokens is the correct HTTP semantic (Conflict).
- Tests properly updated to expect
truefrom the mock.
Checklist:
- Functionality: eliminates race window for double-activation
- Edge cases: concurrent requests handled atomically
- Security: prevents duplicate token activation and associated side-effects
- Code quality: minimal, clear changes
- Tests: CI green, mock return values updated
LGTM — ready to merge.
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Summary
status = 'pending'condition to the UPDATE WHERE clause inactivateMachineToken()so only one concurrent request can succeedChanges
src/shared/src/db/queries/machine-token.ts: UPDATE now uses atomic compare-and-swap, returns success booleansrc/web/src/app/api/machine-tokens/activate/route.ts: Checks activation result, returns 409 on race conflictTest plan
Closes #150