fix(static): don'\''t let zstd_static suppress the gzip fallback#76
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ngx_http_zstd_ok() latches r->gzip_tested=1 / r->gzip_ok=0 as a side effect (inherited from tokers/zstd-nginx-module). The static handler called it under `zstd_static on` BEFORE checking whether the .zst file exists. When the .zst was absent the handler declined — but gzip had already been latched "not ok" for the request, so a later gzip filter or gzip_static handler short-circuited on the cached decision and served identity instead of gzip. The client lost its gzip fallback purely because the zstd module was enabled. Split the shared helper: ngx_http_zstd_accepts() is a side-effect-free acceptance predicate for callers that only need the decision (the static module); ngx_http_zstd_ok() keeps the latching behaviour for the on-the-fly filter, which commits to Content-Encoding: zstd immediately after and must keep gzip off. ngx_http_zstd_ok() is now ngx_inline: the static TU includes the header but no longer calls it, and a plain `static` definition would trip -Werror=unused-function there; an inline definition is exempt. Tests (t/01-static.t): - TEST 26 — zstd_static on, request a plain file with NO sibling .zst through the always-present gzip *filter*; asserts Content-Encoding: gzip. Verified to fail on pre-fix code (gzip suppressed -> identity). - TEST 27 — coexistence with the gzip_static *module*. Documents that gzip_static (a built-in CONTENT_PHASE handler) runs before the dynamic zstd_static handler and so was never bitten by the latch; kept as a coexistence contract (passes on both pre-fix and fixed trees).
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MINOR from module audit.
Problem
ngx_http_zstd_ok()latchesr->gzip_tested=1/r->gzip_ok=0as a side effect. The static handler called it underzstd_static onbefore checking whether the.zstexists. When the.zstwas absent the handler declined — but gzip was already latched "not ok" for the request, so a later gzip filter / gzip_static handler short-circuited and served identity instead of gzip. The client lost its gzip fallback purely because the zstd module was enabled.Fix
Split the shared helper:
ngx_http_zstd_accepts()— side-effect-free acceptance predicate, used by the static module (decision only).ngx_http_zstd_ok()— keeps the latching behaviour for the on-the-fly filter, which commits toContent-Encoding: zstdimmediately after and must keep gzip off. Nowngx_inlineso the static TU (which includes the header but no longer calls it) does not trip-Werror=unused-function.Tests
t/01-static.tTEST 26 —zstd_static on, plain file with no sibling.zst, through the gzip filter; assertsContent-Encoding: gzip. Verified to fail on pre-fix code.gzip_staticmodule. Documents that gzip_static (a built-in CONTENT_PHASE handler) runs before the dynamic zstd_static handler and was never bitten by the latch; kept as a coexistence contract (passes pre-fix and post-fix).Local:
prove t/00 t/01= 1224/1224 PASS.