Files
pixa/internal/imgcache/max_concurrent_processing_internal_test.go
T
sneak 2dd2134f7f
check / check (push) Canceled after 0s
Store a source the way a variant is stored, one row and one file per source URL (closes #308)
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
2026-10-21 14:16:47 +00:00

131 lines
3.4 KiB
Go

package imgcache
import (
"image/color"
"image/jpeg"
"io"
"os"
"testing"
"time"
"sneak.berlin/go/pixa/internal/imageprocessor"
"sneak.berlin/go/pixa/internal/imagerequest"
)
// widthOnlyRequest asks for the test photo at width, its height scaled to
// keep the photo's aspect ratio.
func widthOnlyRequest(fixtures *TestFixtures, width int) *imagerequest.Request {
return &imagerequest.Request{
Source: imagerequest.Source{
Host: fixtures.GoodHost,
Path: testPathPhoto,
},
Transform: imagerequest.Transform{
Size: imagerequest.Size{Width: width},
Format: imagerequest.FormatJPEG,
Quality: 85,
FitMode: imagerequest.FitCover,
},
}
}
// holdProcessingSlot takes one of proc's processing slots and returns the
// func that gives it back. Process takes its slot before it reads its input,
// so once it has read a byte from the pipe it holds the slot, until the pipe
// is closed.
func holdProcessingSlot(
t *testing.T, proc *imageprocessor.ImageProcessor,
) func() {
t.Helper()
input, feed := io.Pipe()
go func() {
_, _ = proc.Process(t.Context(), input, &imagerequest.Transform{})
}()
_, err := feed.Write([]byte{0})
if err != nil {
t.Fatalf("Process call to hold the slot did not start: %v", err)
}
release := func() { _ = feed.Close() }
t.Cleanup(release)
return release
}
// TestService_Get_WaitsForSlotBeforeReadingCachedSource checks that a
// request whose source is cached holds none of it while it waits for a
// processing slot: it reads the cached file only once it has a slot. With
// the only slot held, a request for a new width of the cached 100x100 photo
// waits; the cached file is then rewritten as a 100x50 image before the slot
// is freed, so the request must answer with that image scaled to 40x20.
func TestService_Get_WaitsForSlotBeforeReadingCachedSource(t *testing.T) {
t.Parallel()
svc, fixtures := SetupTestService(t)
svc.processor = imageprocessor.New(
imageprocessor.Params{MaxConcurrentProcessing: 1},
)
// A first request caches the photo as a source.
resp, err := svc.Get(t.Context(), widthOnlyRequest(fixtures, 50))
if err != nil {
t.Fatalf("first Get() error = %v", err)
}
_ = resp.Content.Close()
sourceKey, _, err := svc.cache.LookupSource(t.Context(),
widthOnlyRequest(fixtures, 50))
if err != nil || sourceKey == "" {
t.Fatalf("LookupSource() = %q, %v; want the cached source",
sourceKey, err)
}
release := holdProcessingSlot(t, svc.processor)
var (
waited *ImageResponse
waitedErr error
)
done := make(chan struct{})
go func() {
defer close(done)
waited, waitedErr = svc.Get(t.Context(), widthOnlyRequest(fixtures, 40))
}()
// Give the request time to reach the slot: had it read the cached source
// before waiting, it would have read it by now.
time.Sleep(100 * time.Millisecond)
err = os.WriteFile(svc.cache.srcContent.keyToPath(sourceKey),
generateTestJPEG(t, 100, 50, color.RGBA{0, 0, 255, 255}), 0o600)
if err != nil {
t.Fatalf("failed to rewrite the cached source: %v", err)
}
release()
<-done
if waitedErr != nil {
t.Fatalf("Get() error = %v", waitedErr)
}
defer func() { _ = waited.Content.Close() }()
output, err := jpeg.DecodeConfig(waited.Content)
if err != nil {
t.Fatalf("failed to decode the response: %v", err)
}
if output.Width != 40 || output.Height != 20 {
t.Errorf("response is %dx%d, want 40x20: the request read the cached "+
"source before it had a processing slot", output.Width, output.Height)
}
}