Share one fetch and transcode among concurrent misses (closes #65)

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Author	SHA1	Message	Date
clawbot	ef3ebc462e	Share one fetch and transcode among concurrent misses (closes #65 ) check / check (push) Successful in 4m20s Details Requests that missed the same variant at once each fetched and transcoded it. They now share one call through golang.org/x/sync/singleflight, keyed on the variant cache key. The first request processes the variant with a context that ignores its cancellation but keeps its deadline; the others wait for its result, holding no connection or processing slot, and return as soon as their own context ends. The processing request waits even then, up to its deadline. Each request counts one miss; the processing counts its fetch and transcode once. A panic while processing is reported through the request's Sentry hub, when there is one, and becomes an error instead of stopping pixad. Model: opus-5-5	2026-10-03 15:54:43 +00:00
clawbot	2777d3f784	Test that a shared miss keeps its deadline and reports panics (closes #65 ) A request with a deadline whose fetch waits on its context, as the fetcher does while it waits for a free connection to the host, must return by that deadline. A panic while a variant is being made must be reported through the Sentry hub on the request's context, where the Sentry middleware puts one when sentry_dsn is set. The panic test fails on next, where the panic leaves Get. Model: opus-5-5	2026-10-03 15:53:34 +00:00
clawbot	b36b1abbc8	Test that concurrent misses for one variant share one fetch (closes #65 ) Requests that miss the same variant while its fetch is held must make one fetch and one transcode between them, all get the same image and each count one miss. Variants differing only in quality or fit stay apart. A waiting request whose context ends returns at once; the first request's client leaving does not stop the work. A shared failure reaches every request, the negative cache answers the next one, and an uncached failure is fetched again. A request that has already ended fetches nothing, and a panic comes back as an error. All but the variants test fail on next. Model: opus-5-5	2026-10-03 15:50:55 +00:00

Author

SHA1

Message

Date

clawbot

ef3ebc462e

Share one fetch and transcode among concurrent misses (closes #65 )

check / check (push) Successful in 4m20s

Details

Requests that missed the same variant at once each fetched and
transcoded it. They now share one call through
golang.org/x/sync/singleflight, keyed on the variant cache key. The
first request processes the variant with a context that ignores its
cancellation but keeps its deadline; the others wait for its result,
holding no connection or processing slot, and return as soon as their
own context ends. The processing request waits even then, up to its
deadline. Each request counts one miss; the processing counts its fetch
and transcode once. A panic while processing is reported through the
request's Sentry hub, when there is one, and becomes an error instead
of stopping pixad.

Model: opus-5-5

2026-10-03 15:54:43 +00:00

clawbot

2777d3f784

Test that a shared miss keeps its deadline and reports panics (closes #65 )

A request with a deadline whose fetch waits on its context, as the
fetcher does while it waits for a free connection to the host, must
return by that deadline. A panic while a variant is being made must be
reported through the Sentry hub on the request's context, where the
Sentry middleware puts one when sentry_dsn is set. The panic test fails
on next, where the panic leaves Get.

Model: opus-5-5

2026-10-03 15:53:34 +00:00

clawbot

b36b1abbc8

Test that concurrent misses for one variant share one fetch (closes #65 )

Requests that miss the same variant while its fetch is held must make
one fetch and one transcode between them, all get the same image and
each count one miss. Variants differing only in quality or fit stay
apart. A waiting request whose context ends returns at once; the first
request's client leaving does not stop the work. A shared failure
reaches every request, the negative cache answers the next one, and an
uncached failure is fetched again. A request that has already ended
fetches nothing, and a panic comes back as an error. All but the
variants test fail on next.

Model: opus-5-5

2026-10-03 15:50:55 +00:00

Share one fetch and transcode among concurrent misses (closes #65) #160