feat(github-app): select app by rate limit budget - #5391
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Brend-Smits
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Follow-up to #5269, item 2 of the [#5038 review](#5038 (review)). Stacked on #5282 (manifest transport); review that first. Replaces uniform random GitHub App selection with budget-aware selection, ported from our production fork: - The auth module tracks the last observed `x-ratelimit-remaining` per app, fed by `metricGitHubAppRateLimit` headers and the throttling plugin callbacks. - Selection picks the app with the most budget remaining; apps with no observed state are assumed full. - Apps that hit a secondary rate limit are skipped for 60 seconds; if every app is cooling down, the one with the most budget is used anyway. - Iteration starts at a random offset so concurrent cold-started lambdas do not converge on the same app. Uniform random kept sending ~1/N of traffic to apps that were already exhausted. Selection state is per warm container and converges within a few invocations; a cold container starts as before. - control-plane: 353 tests passed, including six new selection tests (budget preference, unobserved-assumed-full, cooldown skip, all-cooling fallback, single-app short-circuit, explicit appIndex) and a selector-feed test for the rate-limit headers. - ESLint + Prettier clean. Follow-up to #5269 / #5038. Depends on #5282.
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Dependency Review✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.Scanned FilesNone |
edersonbrilhante
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Replaces uniform random GitHub App selection with selection based on the last observed rate-limit budget. Apps under a secondary rate-limit cooldown are temporarily skipped, and randomized starting points spread cold-start traffic across apps.
Uses the credential storage interface introduced on main and preserves the selected app index throughout each operation. Includes a regression test verifying selection from an injected credentials store without reading SSM.
This PR targets
mainand contains only the rate-limit selection change. The manifest prerequisite was merged separately in #5282. Replaces #5283, which was originally merged into the parent feature branch.Validation: 350 control-plane tests passed; TypeScript, ESLint, and diff whitespace checks passed. The commit is signed and verified.
Follow-up to #5269 / #5038.