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 does not end
with its own; 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, as before. Each request counts one
miss; the processing counts its fetch and transcode once. A panic
while processing becomes an error instead of stopping pixad.
Model: opus-5-5
Cache.metaCache was declared and never used, so every cache hit read
and parsed the variant's .meta file. It is now an LRU
(github.com/hashicorp/golang-lru/v2) of up to 10,000 variants' content
types, filled by StoreVariant and by a read of a .meta file, so a hit
for a variant it holds skips the .meta read. Only a type from a .meta
file or a store ever enters memory, never the application/octet-stream
fallback, and a stored type is never replaced by an older one from
disk. The variant file itself is still opened on every hit, so nothing
is served from memory alone.
Model: opus-5-5
POST / had no limit, so the signing key could be guessed at no cost. It
is now limited to 5 attempts per minute per client by a new RateLimit
middleware on github.com/go-chi/httprate; an attempt over the limit gets
429 with Retry-After. It counts by the address the ClientIP middleware
resolved through trusted_proxies (an IPv4-mapped address as its IPv4
address, IPv6 by its /64) and runs after the body-size and CSRF checks,
so every attempt that reaches the key comparison is counted. README says
that with the default trusted_proxies a client with a private address
can choose its counted address, and how to close that.
Model: opus-5-5
Adds CSRF protection to the two cookie-authenticated form posts, POST / (login) and POST /generate, using github.com/gorilla/csrf, the recorded default for this job.
The token key is derived from signing_key with its own HKDF salt, so it needs no new config and survives restarts. The token cookie is separate from the session cookie, which also covers login CSRF, where no session exists yet. Both templates carry the hidden token field.
What a reader would trip over: outside debug mode the library enforces its https Referer origin check, so the TLS-terminating proxy must preserve the Host and Referer headers from the browser or form posts are rejected.
Disclosure: one nolint:gosec on a test constant holding the library field name (G101 false positive).
Model: opus-4-8 (implementation, review); fable-5-1 (landing message)
- Replace gen2brain/avif, gen2brain/webp, disintegration/imaging with govips
- govips uses libvips via CGO for fast native image processing
- Add libheif-dev to Dockerfile for AVIF support
- Add docker-test Makefile target for running tests in Docker
- Update processor.go to use vips API for decode, resize, encode
- Add TestMain to initialize/shutdown vips in tests
- Remove WASM-based libraries (gen2brain) in favor of native codecs
Performance improvement: AVIF encoding now uses native libheif instead of
WASM, significantly reducing encoding time for large images.
Uses github.com/gen2brain/webp - a CGO-free library that uses WASM via
wazero runtime for encoding. WebP decoding was already supported.
- Add gen2brain/webp dependency for encoding
- Implement WebP encoding in processor.go
- Add FormatWebP to SupportedOutputFormats
- Re-enable WebP option in generator form dropdown
- Mark WebP encoding as complete in TODO.md
Implements the Processor interface using disintegration/imaging library.
Supports JPEG, PNG, GIF, WebP decoding and JPEG, PNG, GIF encoding.
Includes all fit modes: cover, contain, fill, inside, outside.