The walk of each storage directory returned the error of a directory it
could not list, or of a source or variant file whose info it could not
read. The pass then stopped before its later checks, every time it ran.
Now reconcileFiles skips a directory it cannot list and a file whose
info it cannot read, temp files included. It logs a warning naming the
path and the error, and the walk goes on. It reads each file's info
once and hands it to sweepStaleTempFile, reconcileVariantFile or
reconcileSourceFile. A file renamed or removed after its directory was
listed is skipped with no warning. A cancelled context still stops the
walk with its error. README.md says so under Storage.
Model: opus-5-5
Each storage directory gets a directory the pass cannot list and a file
whose info it cannot read. Their paths are longer than Linux accepts,
even for root. The test wants a warning naming each path and the error.
It also wants the rest of the pass done: a variant file with no row
adopted, the row of a missing variant file dropped, a source file with
no row removed, and a wrong usage total corrected. A second test puts a
temp file whose info cannot be read in each storage directory and wants
the same warning. On next the first test's pass stops at the first such
directory and returns its error. The second test gets no warning.
Model: opus-5-5
The reconciliation pass dropped a variant's accounting row on any error
reading its file's size, and logged every such file as missing. A file
still on disk then had no row, so eviction no longer counted it against
cache_max_bytes. Now only a missing file (ErrNotFound, which
FileStore.Size returns for it) loses its row, with the same info line.
Any other error keeps the row and logs a warning naming the variant key
and the error, and the pass goes on to the next key. README.md says so
under Storage.
Model: opus-5-5
reconcileVariantRows is given two tracked variants. The first one's
file is a symbolic link to itself, so reading its size fails with an
error other than a missing file. The test wants its row kept, with a
warning naming its key and the error. The second one has no file, and
the test wants its row dropped with the info line for a missing file.
The test fails on next, which drops both rows and logs both files as
missing. The fix follows in the next commit.
Model: opus-5-5
magic.DetectFormat returns an imagerequest.Format. ValidateMagicBytes
returns the format it checked against the upstream Content-Type. The
cache reads a cached source's format from its file's first bytes, as it
reads a variant's. The proxy hands the format to Process. Process
refuses a format that is not a source format, and input libvips would
load with another loader, such as an SVG passing as AVIF.
Format.MIMEType declares each MIME string once, and the fetcher, the
cache's variant read and the Accept matching use it. magic.MIMEType,
magic.ImageFormat, MIMEToImageFormat, magic's SVG detection,
detectFormat, formatFromString, FormatToMIME and Result.InputFormat are
gone.
Model: opus-5-5
imgcache.FileStore is a directory of files named by a hex key, at
<ab>/<cd>/<key>. It writes a file under a temp name, syncs it and renames
it into place. It opens, reports the size of and deletes the file for a
key. The cache keeps its sources in one FileStore and its variants in
another, so ContentStorage and VariantStorage are gone. FileStore has no
Exists: the reconciliation pass checks a variant's file with Size, and the
tests look for the file on disk. Cache.Variant reads the content type from
the file's first bytes itself. storage.go is now filestore.go, and the
unused testdata/red.avif is gone.
Model: opus-5-5
The new package internal/imageproxy holds Proxy, which was imgcache.Service,
with its Config, ImageResponse, CacheStatus and errors. imageproxy.New makes
and registers the counters of upstream fetches and transforms.
internal/imgcache holds the cache only, with its hit and miss counters, and
imgcache.CacheConfig is imgcache.Config. The cache reads and writes each kind
it keeps with one pair of methods: Variant and PutVariant, Source and
PutSource, Failure and PutFailure. Source replaces LookupSource followed by
GetSourceContent. imgcache.go and module.go are gone. The proxy's tests moved
with it. The cache's tests check that the reconciliation pass removes an empty
or cut file and its row. The proxy's tests remove them by hand, then check
that Get fetches or converts again.
Model: opus-5-5
The image request now holds only its source and its transform, exactly what
the variant key covers. The /v1/image/ handler checks the allowlist and
verifies the signature itself with Signer.Verify(req, sig, expires). Both
image handlers keep the URL's expiry as a local value for Cache-Control. The
image service holds no signer, allowlist or AllowHTTP, and ValidateRequest is
gone. The fetcher takes the source and builds its URL with Source.URL from its
own AllowHTTP, so no URL string is built and parsed again. chooseAutoFormat
returns the format it chooses instead of writing into the request. The signed
URL format and every route's answers are unchanged.
Model: opus-5-5
The new package internal/providers builds the cache, the fetcher, the
processor, the image service, the session manager and the encrypted URL
generator from the config. pixad's fx graph provides them with
providers.Constructors(), and handlers.New receives them built. The
server tests build the same graph, with only the fetcher's dial function
replaced. database.New opens the database, so these parts can read it
while fx builds them; the cache's stop hook still runs before the
database's.
Each setting's default is declared in internal/config, and
internal/providers works out the default cache_max_bytes. The cache's
MaxBytes is the one value for the disk cache limit, and 0 turns the disk
cache off. The fetcher and the processor take explicit values.
Model: opus-5-5
Service.Warm, the ImageCache interface, both GenerateSignedURL methods,
signature.ParseParams, imagerequest.ParseImagePath, four symbols of
internal/magic, the image processor's lists of supported formats,
IsEmpty and Count of the allowlist, ssrfSafeDialer, CacheStale,
ErrCacheMiss, ErrNegativeCache, ImageResponse.LastModified and the Load
methods of ContentStorage and VariantStorage had no caller outside
tests. They are gone, with the tests that tested only them.
The handlers tests sign their image URLs with generateSignedURL, a test
helper that builds the URL as the removed generator did. The SSRF dialer
tests call dialSSRFSafe with no operator blocklist, which is all
ssrfSafeDialer did. The tests of ParseImagePath and ContentStorage.Load
call ParseImageURL and LoadWithSize instead. MIMEToImageFormat,
ContentStorage.Store and CleanExpired stay, as pixa calls them.
Model: opus-5-5
The five counts the cache_stats table held are now Prometheus counters in
memory, as fields of the cache. NewCache makes them and registers them on
the registry it is given. pixad gives it Prometheus' default registry,
which /metrics serves; each test gives it a new one. The Increment methods
add to their cache's counters, so counting makes no database call.
cache_stats, Cache.Stats, Service.Stats, CacheStats and the pending counts
are gone, with their tests. The background goroutine now writes only access
times, and its names say so: StartPendingAccessTimeWrites,
StopPendingAccessTimeWrites and pendingaccesstimes.go. The two stop tests
whose write under way was a count now use access times.
Model: opus-5-5
Removes output_content and request_cache, which nothing writes, and every
column that was written but never read: the host, path, query, content_type
and fetched_at of source_content, the content_type and created_at of
variant_content, and the status_code, error_message and fetched_at of
negative_cache.
StoreSource no longer takes the fetch result and LookupSource returns only
the source key. StoreVariant no longer takes a content type and
StoreNegative no longer takes a status code or message, so
extractStatusCode and the status constants, which only fed status_code,
are gone. Reconciliation adopts a variant file without opening it, as its
row no longer records a content type. Tests that set or checked a removed
column follow.
Model: opus-5-5
A hit opens the variant file and nothing else: its content type comes
from the file's first bytes, and a file in no output format is a miss.
Its access time and count, and the access time of a cached source a
miss uses, go without waiting to one background goroutine that writes
them once a second; each kind of access time waits in a channel of
10,000 that drops the rest. Expired negative cache rows are left to
CleanExpired. The .meta files, metaCache, Lookup and golang-lru go,
with their tests; the two reconciliation walks, identical without the
.meta skip, share one. make bench runs a parallel cache hit benchmark
on the host, outside make check.
Model: opus-5-5
A source is now one source_content row and one file named by its
SourceKey, the SHA-256 of its host, path and query, made as the variant
key is. A store writes the file, then upserts the row, and removes the
file when the row cannot be written; an eviction deletes the row, then
the file, with no lock. source_metadata, the JSON files under
cache/metadata/, MetadataStorage, the content lock, the eviction
transaction and its test hook are gone, as is the reconciliation pass
that dropped a source row whose file is missing. Two source URLs
serving the same bytes store them twice.
Model: opus-5-5
The new package internal/imagerequest holds the request type, its two
parts Source and Transform, the Format and Fit types, the dimension and
fit checks, the /v1/image/ path parsing and the variant key; it imports
no other package of pixa. imgcache.ParsedURL, imgcache.ImageRequest,
signature.Request, imageprocessor.Request, the second Size, format and
fit types and the conversions between them are gone. The image
processor takes a Transform only. encurl keeps a private struct with the
token's short CBOR field names. VariantKey moves with the function that
makes it. Tests follow the moved and renamed code; the tests of the
removed conversions go with them.
Model: opus-5-5
A body whose first bytes are not those of the format its Content-Type
names answered 500 on both image routes, was logged as pixa's own
error, and was fetched again on every request. Both routes now answer
415 for each error the first-bytes check returns, and the image service
logs the refused source at warning level. The failure also gets a
negative cache entry, as an upstream error status does, so the source
URL is not fetched again for 5 minutes, and meanwhile an image that
would need that fetch answers 502. README.md says so.
The case of TestService_Get_ConcurrentMissesShareAFailure that expected
such a source to be fetched again now expects the negative cache, as
#280 (comment) allows.
Model: opus-5-5
The reconciliation pass reads a row and stats a file for every cached
file, and it ran on every eviction tick, so on a large cache a pass
longer than the tick was followed by the next one at once. It still runs
at startup and is considered on each tick, but it now starts no sooner
than ten times as long after the last pass ended as that pass took, so
it takes at most about a tenth of the time however large the cache.
Eviction and the removal of expired negative cache rows still run on
every tick. The comments that bound the drift, and README.md, give the
new bound. No existing test changed.
Model: opus-5-5
A size with one side 0 has that side worked out from the source's
proportions by integer division, and nothing kept it at 1 or more. When
it rounded down to 0, libvips was asked for a square: an 8192x1 source
at 100x0 came out 100x100, at 1300x0 it asked for one block of about
39 GB, and some shapes answered 500. Each computed side, and each side
contain, inside and outside work out again from the scale, is now at
least 1. README.md now says what fit=outside does and what a 0 side
means; with fit=outside an 8192x1 source at 100x0 comes out 8192x1, as
covering the size requires.
Model: opus-5-5
The source URL was built by joining the decoded path and query as
text, so a space in the query reached the upstream raw and failed with
502, 100%25.png made a URL Go could not parse and answered 401, and
%20 and %2520 fetched the same path under different cache keys. The
source URL is now built with net/url, so each decoded path and query is
one upstream request matching its signature and cache key; the query
encodes the characters a browser encodes, ' included. The generator page
compares what pixa would fetch with the URL as entered, and answers 400
with the URL to use when they differ, or for a user name and password
or a .. segment.
Model: opus-5-5
A # written as %23 in the source path or query reached the parser
decoded and stayed in the source URL, where Go reads it as the start of
a fragment and drops it before fetching. So each text after the # was
another unsigned spelling of one upstream request, cached under its own
keys. An image URL whose decoded source path or query holds a # is now
refused with 400, signed or not, and README.md's rule for writing a
source path and query says a # cannot be part of either.
Model: opus-5-5
A ? written into the host segment as %3F reached the parser decoded,
so cdn.example.com?x=1 passed the allowlist as cdn.example.com, fetched
the host's root path with that query, and was cached under its own keys:
another unsigned spelling of one upstream request. The host segment is
now accepted only as a host name, an IPv4 address or a bracketed IPv6
address, with an optional port, and anything else is refused with 400.
An IPv6 address without brackets is now refused instead of needing a
signature; a host name outside ASCII is refused, its punycode accepted.
Model: opus-5-5
The README gave no way to put a source URL's query into a signed image
URL, and GenerateSignedURL built one that failed: the route parsed
chi's wildcard, which keeps the path as the client wrote it, so one
%2F, %3B or %2C left the %3F undecoded and the signature failed. The
route now parses the decoded path, GenerateSignedURL writes Go's own
encoding of it, and the README says the ? before the query, any ? in it
and every % must be percent-encoded, with a signed example. The path
traversal check no longer reads the query and accepts a literal %, while
a double-encoded .. stays refused. A percent-escape in a source path is
now decoded once.
Model: opus-5-5
The default max_concurrent_processing was one image per CPU pixa sees,
so in a container with no CPU limit on a 48-CPU host pixa processed 48
images at once. It is now half the CPUs, rounded down and at least 1,
defined once in internal/config; PIXA_MAX_CONCURRENT_PROCESSING stays
the override, and a value that is not a whole number of at least 1
stops startup. "Running under upaas" gives the worst-case memory, 4.2
GiB per image (the largest peak measured over every source format and
kind at 8192x8192) plus the upstream buffers, and the temporary file
libvips keeps under /tmp. The two existing tests expect the new
default, as the owner allowed.
Model: opus-5-5
The dotfiles, REPO_POLICIES.md and the standard scripts are fetched
whole from sneak/prompts e3f79c4, with pixa's own entries kept after
them. Check builds pass a new CACHEBUST build argument instead of
--no-cache, and every Dockerfile stage declares it first, so every RUN
step still runs while Go's build cache is kept. Lint runs golangci-lint
v2.14.0, and the test phase runs on the Debian Go image. Of the two new
lint findings, one is fixed and one (gosec G703 on the fixed config file
locations) is suppressed. The agent guidance moves unchanged from
CLAUDE.md to AGENTS.md.
Deviation: the workflow keeps its docker-smoke step while issue 203
waits on the owner.
Model: opus-5-5
A crash could leave a cached source or transformed image empty or cut
short, and pixa then served it, or fetched it again forever. Source and
transformed image files, and the .meta file beside each transformed
image, are now written under a temporary name, synced, renamed into
place and their directory synced; a failed directory sync removes the
renamed file. The reconciliation pass compares each cached file's size
with the size its row records and removes a file that is empty or of
another size, with its rows and a warning. Requests compare no sizes.
Not verified by a test: the syncs, and the removal after a failed sync.
Model: opus-5-5
Process looked at its context only while waiting for a processing
slot, so a transcode kept its slot and worked on after its request's
downstream_timeout. acquireSlot now gives the slot back when the
context has ended by the time it has one, and encode returns the
context's error without beginning. govips gives pixa no way to stop
libvips once an encode has begun, so that encode keeps its slot. A
request waiting on a shared transcode stopped at the first request's
deadline is answered 503, not 500. README.md "Routes" says both.
Model: opus-5-5
A negative cache row was deleted only when its URL was requested
again, so a client asking for a new missing path each time grew the
database without limit. The eviction goroutine now removes expired rows
at startup and on every tick, so a row stays about NegativeTTL plus one
eviction interval. It deletes at most 1000 rows per statement, so a
request on the one database connection waits behind one batch at most.
The goroutine now also runs when the disk cache is disabled, since the
negative cache is used either way.
Model: opus-5-5
Get checked the negative cache before the variant cache, so after one
failed fetch of a source every variant of it answered 502 for five
minutes, also one on disk or one that could be made from the cached
source. The check now sits at the start of fetchAndProcess, which runs
only when no cached source can be used. A refusal from the negative
cache now counts as a miss.
Model: opus-5-5
With `cdn.example.com` allowlisted, other letter cases and a host with a port also passed the allowlist; each spelling was fetched and cached on its own with its own per-host connection limit, and a port let an unsigned URL reach any port of the host.
The image URL parser now lower-cases the host and refuses one holding `@` with 400. A host followed by `:`, with or without a port (read as Go's URL parser reads it, unbracketed IPv6 included), never counts as allowlisted, so it needs a signature. The host is signed lower-cased, as the URL writes it, so a signature made over an upper-case spelling is refused with 401.
Model: opus-5-5
The signed data and the cache key joined host, path and query with ":" and no escaping, so path /a:b with no query and path /a with query b: gave the same string: a URL signed for https://h/a:b verified for https://h/a?b:, and the two shared a cached image. Both now write each % in the path and the query as %25 and each : as %3A before joining them. The host never holds / and the path always starts with /, so the joined string reads back one way only. A path and query holding neither character are signed and keyed as before, so the existing known-answer vectors and the README example are unchanged; new vectors cover the escaped cases. Signature Specification in README.md states the escaping.
Model: opus-5-5
A side given as 0 is computed from the source's proportions, and
nothing held it to 8192: 0x8192 of a 3000x600 source was resized to
40960x8192 and encoded. Process now refuses such a size with
ErrOutputTooLarge once it knows the source's dimensions, before the
resize and the encode, and both image routes answer it 400 with the
JSON error body. It is a processing error, not a failed fetch, so it
is never negative-cached. imgcache.MaxDimension is now
imageprocessor.MaxOutputDimension, so the request limit and the output
limit are one value. README.md says it under Routes and Encrypted URLs.
Model: opus-5-5
CacheConfig.CacheTTL was set to DefaultCacheTTL (24 hours) and never
read, so cached images never expired. Remove the field, the constant
and the line that set it. Cached source and transformed images stay
until eviction removes them to keep the cache within cache_max_bytes.
A new test caches a source and a transformed image, sets every time
pixa stores for them two days back (database rows, metadata files and
file times), and checks that both are still served from the cache
without a new upstream fetch.
Existing tests lose only the CacheTTL line of their cache config.
Model: opus-5-5
TestService_Get_ReturnsByItsDeadline failed on a busy host because its
request, past its deadline, still waited to write its miss count, a write
with no deadline; in pixad that write waits for the one database
connection every request shares. Each count write now keeps the request's
deadline but not its cancellation. A count not written by then is kept in
memory, where Stats includes it, and one goroutine of the cache writes
those counts one UPDATE at a time, and once more at shutdown before the
database closes. The test phase also runs go test with -parallel 4: on a
busy host, as many tests at once as there are CPUs wait so long to be
scheduled that a timed request can fail.
Model: opus-5-5
A /v1/image/ URL whose last segment is a size with no format, such as
800x600 or orig, is served as JPEG XL and signed as jxl, so it shares
the signature of the same URL ending in .jxl. An encrypted URL whose
token holds no format is served as JPEG XL, as encurl.DefaultFormat is
now jxl. The generator page selects JPEG XL by default, and a form
with an empty format, or none, makes a URL whose name ends in .jxl.
The image processor no longer takes an empty format as orig: both
routes give every request a format, so it refuses a request with none
instead of keeping a second default. auto still ends with JPEG.
Model: opus-5-5
A JPEG XL source is accepted, and orig of one is JPEG XL. The format
jxl works in plain and encrypted URLs and on the generator page,
served as image/jxl; auto chooses it first when Accept names
image/jxl.
govips sends libvips a JPEG XL distance, which overrides the quality,
so q becomes a distance, keeping 100 lossy. Metadata is removed from
the image before the JPEG XL save, as govips cannot have libvips strip
it, and the image is given 72 dpi so that the EXIF block libvips 8.16
adds holds nothing from the source. The sRGB conversion moved ahead of
the format switch, and a CMYK image with no ICC profile is converted
to sRGB, as libvips cannot save CMYK as JPEG XL.
Model: opus-5-5
UsageBytes now reads the new cache_usage row, which triggers on
source_content and variant_content keep up to date in the statement
that adds, removes or resizes a row. The reconciliation pass reads both
tables 1000 rows per query, sums them, and corrects the total when it
differs, unless a row changed while it summed. Source rows now get
last_accessed_at when added, so choosing source images to evict reads
that column's index instead of sorting the whole table. Stats still
sums the tables, now in pages: an existing test drops both tables and
expects that sum to fail.
Model: opus-5-5
script/bootstrap --cgo installs vips-jxl when the package manager it
uses is apk, as Alpine's vips package lacks JPEG XL support; the nix
and brew libvips include it, as does apt's from Debian 12 and Ubuntu
24.04 on. The runtime stage of the Dockerfile installs vips-jxl too.
imgcache.NewService calls the new imageprocessor.CheckJPEGXLSupport
before it builds the image processor and fails with its error, which
names the fix, so pixad does not start without the support. JPEG XL
becomes the default output later in the issue. New tests check the
support and save an image as JPEG XL with govips and load it back.
Model: opus-5-5
auto is a format in the /v1/image/ path, an encrypted URL's token and
the generator page. Once the signature or token is checked, pixa
chooses AVIF when Accept names image/avif, else WebP when it names
image/webp, else JPEG when the most specific of image/jpeg, image/* and
*/* allows it or Accept is absent. q=0 refuses a format; a header
allowing none of the three answers 406, one that does not parse 400.
The signature and token cover auto itself; the cache key and ETag use
the chosen format. Answers from then on carry Vary: Accept.
Model: opus-5-5
TestImageProxyFlow in internal/server starts the database, handlers and
middleware from the constructors pixad uses, with a fresh state
directory, and replaces only the upstream origin with an httptest
server. For a resize with a format change and for orig it checks a 200
MISS with the right type and size, then a HIT after one upstream request,
and the files and rows the cache keeps. Two optional test seams make
that possible: httpfetcher.Config.DialContext and handlers.Params.Fetcher.
pixad sets neither and the config file and environment cannot, and tests
show production still uses the checked dialer and builds its own fetcher.
Model: opus-5-5
TestPeriodicReconciliationAdoptsFileThatAppearsAfterStartup slept for
three eviction intervals before writing its file, so on a slow start the
startup pass could still be running and adopt the file itself, and the
test passed without a periodic pass. It now holds the test database's
only connection until the startup pass waits for it, writes the file and
lets the connection go, as TestEvictionRunsOnPeriodicSchedule does, so
only a periodic reconciliation pass can adopt the file. Test only.
Model: opus-5-5
The default cache_max_bytes was 75% of the space free at startup. The
cache's own files are not free space, so a fuller cache got a smaller
limit after a restart and eviction then deleted most of it. The default
is now 75% of the sum of the free space and what the cache already holds
by its own size accounting, at least 500 MiB. The cache works it out
when it opens, after the database is open, so the computation and its
tests moved from internal/config to internal/imgcache. The config only
records whether cache_max_bytes was set; newCacheConfig in the handlers
turns the disk cache off only for an explicit 0, and is tested for an
omitted, a zero and a positive value.
Model: opus-5-5
The test wrote each variant file and then inserted its accounting row by
hand while the evictor was running. A reconciliation pass between the two
steps adopted the file first, and the hand insert failed on the unique key.
The test now writes the files only, while it holds the test database's
only connection, so the evictor's startup pass waits after walking the
still empty variant directory. A periodic reconciliation pass then adopts
the files and the eviction pass after it evicts them; no write-pressure
notification fires. The test waits until two of the three files are gone,
then checks that usage is within the limit and that no row points at a
missing file.
Model: opus-5-5
Every response carries X-Request-Id, the upstream fetch sends it, and
the "upstream fetched", "image converted" and "image served" lines log
it as request_id. pixa's own RequestID middleware keeps a request's own
ID only when it is at most 64 letters, digits, '-', '_' or '.', and
otherwise makes a random one with crypto/rand, so nothing a client
chooses freely and nothing about the host reaches upstream. /v1/e/ now
sets ETag, answers a matching If-None-Match with 304 and is routed for
HEAD, through notModified, which both image handlers call. No Vary is
added: go-chi/cors already sends Vary: Origin.
Model: opus-5-5
StartEviction runs the eviction goroutine with its own context, which
StopEviction cancels in place of the old stop channel, so a pass in
progress stops at its next database call, file, row or eviction
candidate instead of running to completion, and no new pass starts.
StopEviction takes a context: when it ends before the goroutine exits,
StopEviction stops waiting and returns an error wrapping it. The
handlers' stop hook passes fx's stop context, so an eviction still
running at fx's stop deadline fails the stop and the exit code is 1.
A stop logs at most one warning.
Model: opus-5-5
Purge only returned an error and nothing called it, so it is gone from
the ImageCache interface and from Service, along with its error value.
It can be added back when something needs it; eviction reclaims disk
space meanwhile. The SignatureValidator, Allowlist and Storage
interfaces in imgcache.go had no implementers and no users, and
described types that look different from the real ones, so they are
deleted. No behaviour changes.
Model: opus-5-5
Each upstream host's semaphore now counts the fetches holding or waiting
for one of its slots, and is removed from hostSems when the last of them
gives its slot back or stops waiting, so a long-running pixad no longer
keeps one semaphore per host it ever fetched from.
VariantStorage.Delete removes the variant's .meta file too, a missing one
not being an error; DeleteWithMeta, which eviction called for that, is
gone.
Model: opus-5-5
fx alone handles SIGINT and SIGTERM; the server's own handler, which
only cancelled a context that fx's stop did not wait for, is gone.
fx's Run exits with the shutdown's code: the one a shutdown request
carries, 0 for a signal, 1 when the app fails to start or stop.
A listen error asks fx to shut down with exit code 1. A Sentry DSN that
cannot be used fails the server's start hook, so fx stops what had
already started. The server's stop hook stops the HTTP server, then
waits for the images still being processed, both within
ShutdownTimeout; images still being processed after that are logged and
fail the stop, so the exit code is 1.
Model: opus-5-5
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
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
Nothing bounded total in-flight work, so a burst of cache misses across
hosts could exhaust memory. Two settings now do: max_concurrent_processing
(default the CPUs Go uses) and upstream_connections (default 64, beside
the per-host limit). A request that finds either full waits up to 10
seconds, then gets 503; a slot is released on every path. No request
holds source bytes while it waits: a cached source is read only after
the processing slot is taken, and a fetched one only while it holds its
upstream connection. libvips runs one worker thread per image with its
operation cache off. Both waits count toward downstream_timeout, as the
README says.
Model: opus-5-5
clawbot