5 Commits
Author SHA1 Message Date
sneak 58da57ca49 Test that CleanExpired removes more than one batch of expired rows
check / check (push) Canceled after 0s
TestCleanExpiredRemovesMoreThanOneBatch stores one expired negative
cache row more than a batch holds and calls CleanExpired alone, so a
CleanExpired that stops after its first batch fails it.

Model: opus-5-5
2026-10-15 08:53:52 +00:00
sneak 98bce3bb1a Delete expired negative cache rows in batches
CleanExpired deletes at most 1000 expired rows per statement and starts
no further statement once its context ends, so a request on the one
database connection waits behind one batch at most.

Model: opus-5-5
2026-10-15 07:45:11 +00:00
sneak 01434ecf3b Test that expired negative cache rows are deleted in batches
One statement deletes one batch and no more, CleanExpired removes the
rest, and it deletes nothing once its context has ended.

Model: opus-5-5
2026-10-15 07:44:49 +00:00
sneak 88fe5c6fed Remove expired negative cache rows in the eviction loop (closes #244)
A negative cache row was deleted only when its source URL was requested
again after it expired, and CleanExpired was never called, so a client
asking for a new missing path each time grew the database without
limit. The eviction goroutine now calls CleanExpired at startup and on
every periodic tick, so a row stays at most NegativeTTL plus one
interval. The goroutine also starts with the disk cache disabled, where
reconciliation and eviction already do nothing, since the negative
cache is used either way.

Model: opus-5-5
2026-10-15 07:44:49 +00:00
sneak fe33fc16c7 Test that the eviction loop removes expired negative cache rows
A failed fetch stored in the negative cache must be removed by the
eviction loop once it has expired, although its URL is never requested
again, with the disk cache enabled and disabled; a row that has not
expired stays. Fails until the fix for
#244 lands.

Model: opus-5-5
2026-10-15 07:44:49 +00:00
7 changed files with 29 additions and 284 deletions
+4 -13
View File
@@ -200,10 +200,9 @@ path under `/v1/` answers 200, in maintenance mode too.
`image_requests_per_minute` (below); 415 when the upstream answers with a
`Content-Type` that is not one of the source formats (below), or with an image
whose first bytes libvips reads as another format; 502 when the upstream
answered with an error status, and for 5 minutes after that for an image of
the same source URL that pixa can neither serve from its cache nor make from
the source image still in its cache; 503 when pixa is busy or in maintenance
mode; 500 for any other failure.
answered with an error status, and for 5 minutes after that for the same
source URL; 503 when pixa is busy or in maintenance mode; 500 for any other
failure.
- `GET` or `HEAD` `/v1/e/<token>/<name>` — an image through an encrypted URL
(see Encrypted URLs). Needs: nothing but the URL. Answers: 200; 304 when
`If-None-Match` matches the image's `ETag`; 400 for a token that does not
@@ -419,9 +418,7 @@ HMAC-SHA256(secret, "host:path:query:width:height:format:expiration:quality:fit"
Where:
- `host` — source host as the URL writes it up to the first `/`, in lower case,
keeping an IPv6 address's brackets and any `:` and port after it (e.g.
`cdn.example.com`, `cdn.example.com:8443`, `[2001:db8::1]:8443`)
- `host` — source origin hostname (e.g. `cdn.example.com`)
- `path` — source path (e.g. `/photos/cat.jpg`), with each `%` written as `%25`
and each `:` as `%3A`, so `/photos/a:b.jpg` is signed as `/photos/a%3Ab.jpg`
- `query` — source query string, empty string if none, with `%` and `:` written
@@ -476,12 +473,6 @@ entry that is neither a host name (letters, digits, hyphens, underscores and
dots, with at most one leading dot) nor an IP address, such as one with a port
or a `*.` wildcard, aborts startup.
pixa lower-cases the host of a `/v1/image/` URL before anything else uses it, so
`CDN.Example.com` is matched, fetched, cached and counted against
`upstream_connections_per_host` as `cdn.example.com`. Such a URL whose host has
a port, as in `cdn.example.com:8443`, or a `:` with no port, needs a signature
even when the host is allowlisted. A host holding `@` is refused with 400.
### Configuration
Every setting can be given as an environment variable, in a YAML config file
+8 -29
View File
@@ -30,6 +30,14 @@ P2: security: per-origin rate limiting
# Completed Steps
- 2026-10-15 a `:` in the source path or query no longer moves where the path
ends and the query begins (closes #247): the signed data and the cache key
joined host, path and query with `:` and no escaping, so a URL signed for
`https://h/a:b` verified for `https://h/a?b:`; the two also shared a cache
key, and whichever was fetched first was served for both. In both, the path
and the query now have each `%` written as `%25` and each `:` as `%3A`; a path
and query holding neither are signed and keyed as before. Signature
Specification in `README.md` says so.
- 2026-10-15 expired negative cache rows are removed on a schedule (closes
#244): the row of a failed fetch, which makes pixa answer 502 for that source
URL for 5 minutes, was deleted only when the same URL was requested again
@@ -41,35 +49,6 @@ P2: security: per-origin rate limiting
expired. The goroutine runs with the disk cache disabled
(`cache_max_bytes: 0`) too, where it does nothing else, as the negative cache
is used either way.
- 2026-10-15 a cached variant is served while its source URL is in the negative
cache (closes #245): `Get` checked the negative cache before the variant
cache, so once a fetch of the source failed, as one does when another variant
misses after the source was evicted and the upstream is down, every variant of
that source answered 502 for 5 minutes, also one on disk or one that could be
made from the cached source. The negative cache is now checked only just
before a fetch from the upstream, so a cached variant is served and a variant
not in the cache is made from the cached source when there is one. `README.md`
says so under `/v1/image/`. A refusal from the negative cache now counts as a
miss, as any other request that misses the variant cache does.
- 2026-10-15 the host of a `/v1/image/` URL is lower-cased, and one with a port
needs a signature (closes #246): with `cdn.example.com` allowlisted,
`CDN.Example.com` and `cdn.example.com:8443` passed the allowlist too, and
each spelling was fetched and cached on its own and had connections of its own
under `upstream_connections_per_host`. The image URL parser now lower-cases
the host and refuses one holding `@`, which a URL reads as a user name and
password, with 400. A host with a port, or with a `:` and no port, needs a
signature even when it is allowlisted. That is checked in the image service,
not in `allowlist.IsAllowed`, which also matches `referer_blocklist`, where a
`Referer` is blocked whatever its port. A URL is signed over its host as it
writes it, in lower case, with any IPv6 brackets, `:` and port kept.
- 2026-10-15 a `:` in the source path or query no longer moves where the path
ends and the query begins (closes #247): the signed data and the cache key
joined host, path and query with `:` and no escaping, so a URL signed for
`https://h/a:b` verified for `https://h/a?b:`; the two also shared a cache
key, and whichever was fetched first was served for both. In both, the path
and the query now have each `%` written as `%25` and each `:` as `%3A`; a path
and query holding neither are signed and keyed as before. Signature
Specification in `README.md` says so.
- 2026-10-15 the example config allowlists no host (closes #249): it allowlisted
`github.com` and `user-images.githubusercontent.com`, where anyone can put an
image, so a deployment set up as Getting Started says served those images to
@@ -95,71 +95,6 @@ func TestNegativeCache_Expired(t *testing.T) {
}
}
// TestService_Get_ServesCachedVariantOfNegativeCachedURL caches a variant of
// the test photo, then keeps a failed fetch of the photo's URL in the negative
// cache, as a failed fetch for another variant does once the source has been
// evicted. The cached variant is still served, and a variant not in the cache
// is made from the cached source. Once the source is evicted, a variant not in
// the cache needs a fetch and is refused.
func TestService_Get_ServesCachedVariantOfNegativeCachedURL(t *testing.T) {
t.Parallel()
svc, fixtures := SetupTestService(t)
resp, err := svc.Get(t.Context(), photoVariant(fixtures, 85, FitCover))
if err != nil {
t.Fatalf("Get() first request error = %v", err)
}
_ = resp.Content.Close()
err = svc.cache.StoreNegative(t.Context(), photoVariant(fixtures, 85, FitCover),
httpStatusBadGateway, "upstream answered 503")
if err != nil {
t.Fatalf("StoreNegative() error = %v", err)
}
resp, err = svc.Get(t.Context(), photoVariant(fixtures, 85, FitCover))
if err != nil {
t.Fatalf("Get() of the cached variant error = %v", err)
}
_ = resp.Content.Close()
if resp.CacheStatus != CacheHit {
t.Errorf("cached variant CacheStatus = %q, want %q",
resp.CacheStatus, CacheHit)
}
resp, err = svc.Get(t.Context(), photoVariant(fixtures, 40, FitCover))
t.Logf("Get() of a variant made from the cached source: error = %v", err)
if err != nil {
t.Fatalf("Get() of a variant made from the cached source error = %v", err)
}
_ = resp.Content.Close()
contentHash, _, err := svc.cache.LookupSource(t.Context(),
photoVariant(fixtures, 85, FitCover))
if err != nil || contentHash == "" {
t.Fatalf("LookupSource() = %q, %v, want the cached source", contentHash, err)
}
err = svc.cache.evictSourceBlob(t.Context(), contentHash)
if err != nil {
t.Fatalf("evictSourceBlob() error = %v", err)
}
_, err = svc.Get(t.Context(), photoVariant(fixtures, 60, FitCover))
t.Logf("Get() of a variant whose source was evicted: error = %v", err)
if !errors.Is(err, ErrNegativeCached) {
t.Errorf("Get() of a variant whose source was evicted error = %v, want %v",
err, ErrNegativeCached)
}
}
// TestEvictionLoopRemovesExpiredNegativeCacheRows stores a failed fetch
// that expires a second later and starts the eviction loop with a short
// interval: a later tick must remove its row although its URL is never
+17 -31
View File
@@ -9,7 +9,6 @@ import (
"log/slog"
"net/url"
"runtime/debug"
"strings"
"time"
"github.com/dustin/go-humanize"
@@ -130,13 +129,25 @@ func NewService(cfg *ServiceConfig) (*Service, error) {
var ErrNegativeCached = errors.New("request is in negative cache (recently failed)")
// Get retrieves a processed image, fetching and processing if necessary.
// While its source URL is in the negative cache, a cached variant is still
// served and a variant not in the cache is still made from a cached source;
// only a request that needs the source fetched is refused.
func (s *Service) Get(ctx context.Context, req *ImageRequest) (*ImageResponse, error) {
// Propagate AllowHTTP setting to the request
req.AllowHTTP = s.allowHTTP
// Check negative cache first - skip fetching for recently-failed URLs
negHit, err := s.cache.checkNegativeCache(ctx, req)
if err != nil {
s.log.Warn("negative cache check failed", "error", err)
}
if negHit {
s.log.Debug("negative cache hit",
"host", req.SourceHost,
"path", req.SourcePath,
)
return nil, fmt.Errorf("%w: %w", httpfetcher.ErrUpstreamError, ErrNegativeCached)
}
// Check variant cache first (disk only, no DB)
result, err := s.cache.Lookup(ctx, req)
if err != nil {
@@ -207,16 +218,7 @@ func (s *Service) ValidateRequest(req *ImageRequest) error {
return fmt.Errorf("invalid source URL: %w", err)
}
// An allowlist entry names no port, so a host followed by ":", with or
// without a port, needs a signature. The port is read from the parsed
// URL, as the fetcher reads it: in an IPv6 address written without
// brackets, such as 2001:db8::1:8443, it is what follows the last ":".
// This is checked here and not in allowlist.IsAllowed, which also matches
// referer_blocklist, where a Referer must be blocked whatever its port.
hostHasPort := parsedURL.Port() != "" ||
strings.HasSuffix(parsedURL.Host, ":")
if !hostHasPort && s.allowlist.IsAllowed(parsedURL) {
if s.allowlist.IsAllowed(parsedURL) {
return nil
}
@@ -421,28 +423,12 @@ func (s *Service) processFromSourceOrFetch(
// fetchAndProcess fetches from upstream, processes, and caches the result.
// It counts the fetch with the bytes read from upstream, including when
// reading the response or a later step fails. It fetches nothing while the
// source URL is in the negative cache.
// reading the response or a later step fails.
func (s *Service) fetchAndProcess(
ctx context.Context,
req *ImageRequest,
cacheKey VariantKey,
) (*processedVariant, error) {
// Check negative cache - skip fetching for recently-failed URLs
negHit, err := s.cache.checkNegativeCache(ctx, req)
if err != nil {
s.log.Warn("negative cache check failed", "error", err)
}
if negHit {
s.log.Debug("negative cache hit",
"host", req.SourceHost,
"path", req.SourcePath,
)
return nil, fmt.Errorf("%w: %w", httpfetcher.ErrUpstreamError, ErrNegativeCached)
}
// Fetch from upstream
sourceURL := req.SourceURL()
@@ -250,97 +250,6 @@ func TestService_ValidateRequest_SignatureExactHostMatch(t *testing.T) {
}
}
// TestService_ValidateRequest_HostWithPortNeedsSignature verifies that a host
// followed by a port, or by a colon with no port, matches no allowlist entry,
// so that a request for it without a signature is refused, while the same
// host with no port is allowlisted.
func TestService_ValidateRequest_HostWithPortNeedsSignature(t *testing.T) {
t.Parallel()
svc, _ := SetupTestService(t,
WithSigningKey(testSigningKey),
WithAllowlist(testHostCDN, "203.0.113.5", "2001:db8::1"),
)
tests := []struct {
host string
allowlisted bool
}{
{testHostCDN, true},
{"cdn.example.com:8443", false},
{"cdn.example.com:443", false},
{"cdn.example.com:", false},
{"203.0.113.5", true},
{"203.0.113.5:8080", false},
{"[2001:db8::1]", true},
{"[2001:db8::1]:8443", false},
}
for _, tt := range tests {
t.Run(tt.host, func(t *testing.T) {
t.Parallel()
req := &ImageRequest{
SourceHost: tt.host,
SourcePath: testPathCat,
Size: Size{Width: 50, Height: 50},
Format: FormatJPEG,
Quality: 85,
FitMode: FitCover,
}
err := svc.ValidateRequest(req)
t.Logf("ValidateRequest() for host %q with no signature: %v",
tt.host, err)
if allowlisted := err == nil; allowlisted != tt.allowlisted {
t.Errorf("host %q served without a signature = %v, want %v",
tt.host, allowlisted, tt.allowlisted)
}
})
}
}
// TestService_ValidateRequest_UnbracketedIPv6PortNeedsSignature verifies that
// an allowlisted IPv6 address written without brackets and followed by a
// port, or by a colon with no port, needs a signature. Go's URL parser, which
// the fetcher uses, reads 2001:db8::1:8443 as the host 2001:db8::1 with the
// port 8443.
func TestService_ValidateRequest_UnbracketedIPv6PortNeedsSignature(
t *testing.T,
) {
t.Parallel()
svc, _ := SetupTestService(t,
WithSigningKey(testSigningKey),
WithAllowlist("2001:db8::1"),
)
for _, host := range []string{"2001:db8::1:8443", "2001:db8::1:"} {
t.Run(host, func(t *testing.T) {
t.Parallel()
req := &ImageRequest{
SourceHost: host,
SourcePath: testPathCat,
Size: Size{Width: 50, Height: 50},
Format: FormatJPEG,
Quality: 85,
FitMode: FitCover,
}
err := svc.ValidateRequest(req)
t.Logf("ValidateRequest() for host %q with no signature: %v",
host, err)
if err == nil {
t.Errorf("host %q served without a signature, want refused",
host)
}
})
}
}
func TestService_Get_InvalidFile(t *testing.T) {
t.Parallel()
-12
View File
@@ -15,7 +15,6 @@ import (
var (
ErrInvalidPath = errors.New("invalid image path")
ErrMissingHost = errors.New("missing source host")
ErrInvalidHost = errors.New("invalid source host")
ErrMissingSize = errors.New("missing size specification")
ErrInvalidSize = errors.New("invalid size format")
ErrInvalidFormat = errors.New("invalid or unsupported format")
@@ -144,17 +143,6 @@ func parseImageComponents(remainder string) (*ParsedURL, error) {
return nil, ErrMissingHost
}
// A URL reads what comes before "@" as a user name and password, and the
// rest as the host
if strings.Contains(host, "@") {
return nil, fmt.Errorf("%w: %q holds @", ErrInvalidHost, host)
}
// Host names do not depend on letter case, so the allowlist, the upstream
// connection limits, the cache and the signature see one spelling of each
// host
host = strings.ToLower(host)
// Extract query string if present in path
if qIndex := strings.Index(path, "?"); qIndex != -1 {
query = path[qIndex+1:]
@@ -234,49 +234,6 @@ func TestParseImagePath(t *testing.T) {
}
}
// TestParseImagePath_LowerCasesHost verifies that the host is lower-cased, so
// that every spelling of its letter case is the same host to the allowlist,
// the upstream connection limits and the cache, and that the path keeps its
// case.
func TestParseImagePath_LowerCasesHost(t *testing.T) {
t.Parallel()
got, err := ParseImagePath("CDN.Example.COM/Photos/Cat.jpg/800x600.webp")
if err != nil {
t.Fatalf("ParseImagePath() error = %v", err)
}
t.Logf("parsed host %q, path %q", got.Host, got.Path)
if got.Host != testHostCDN {
t.Errorf("Host = %q, want %q", got.Host, testHostCDN)
}
if got.Path != "/Photos/Cat.jpg" {
t.Errorf("Path = %q, want %q", got.Path, "/Photos/Cat.jpg")
}
}
// TestParseImagePath_RefusesUserinfo verifies that a host holding "@" is
// refused: a URL reads what comes before the "@" as a user name and password
// and the rest as the host.
func TestParseImagePath_RefusesUserinfo(t *testing.T) {
t.Parallel()
for _, input := range []string{
"user@cdn.example.com/photos/cat.jpg/800x600.webp",
"user:password@cdn.example.com/photos/cat.jpg/800x600.webp",
} {
got, err := ParseImagePath(input)
t.Logf("ParseImagePath(%q) = %+v, error = %v", input, got, err)
if !errors.Is(err, ErrInvalidHost) {
t.Errorf("ParseImagePath(%q) error = %v, want %v",
input, err, ErrInvalidHost)
}
}
}
func TestParsedURL_ToImageRequest(t *testing.T) {
t.Parallel()