ADR-014 item 2 — a single per-egress-IP rate gate shared by every caption
fetch — was specced but only per-video backoff (rate_limited_at) shipped.
Build the real gate now: it is load-bearing once ADR-018 puts auto-summarize
on an in-process schedule across multiple users (all fetches leave one pod's
egress IP, concurrently with live "Summarize" clicks — without a shared gate
that self-inflicts 429s every cycle).
globalFetchGate (golang.org/x/time/rate, default 2s/req burst 1) is consulted
in httpDo before every live outbound fetch — player, watch-page, timedtext —
so the scheduler runners and the web click-path serialise through one limiter
regardless of how many users/goroutines are upstream. The test seam
(a.transport != nil) skips the gate so fakes are not throttled.
TAPIR_FETCH_RATE (Go duration, default 2s, 0 = unlimited) wires SetFetchRate in
cmdRun; the existing per-video backoff stays as the complementary 429 handler.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
mathiasandClaude Opus 4.8
f5021a8436