Add µPaaS deployment setup for fsn1app1

- Add Docker HEALTHCHECK instruction probing /.well-known/healthcheck.json
  (30s interval, 5s timeout, 10s start period, 3 retries) for µPaaS
  container health verification
- Create deploy/README.md with full µPaaS app configuration reference
  (app name, repo URL, branch, env vars, volumes, ports, production config)
- Add Deployment section to README.md linking to deploy docs
- Add deploy/ to .dockerignore (docs not needed in build context)

.dockerignore

@@ -6,3 +6,4 @@
 node_modules
 bin/
 data/
+deploy/

Dockerfile

@@ -75,4 +75,7 @@ WORKDIR /var/lib/pixa
 
 EXPOSE 8080
 
+HEALTHCHECK --interval=30s --timeout=5s --start-period=10s --retries=3 \
+    CMD wget -q --spider http://localhost:8080/.well-known/healthcheck.json
+
 ENTRYPOINT ["/usr/local/bin/pixad", "--config", "/etc/pixa/config.yml"]

README.md

@@ -125,6 +125,17 @@ See `config.example.yml` for all options with defaults.
 - **Metrics**: Prometheus
 - **Logging**: stdlib slog
 
+## Deployment
+
+Pixa is deployed via
+[µPaaS](https://git.eeqj.de/sneak/upaas) on `fsn1app1`
+(paas.datavi.be). Pushes to `main` trigger automatic builds and
+deployments. The Dockerfile includes a `HEALTHCHECK` that probes
+`/.well-known/healthcheck.json`.
+
+See [deploy/README.md](deploy/README.md) for the full µPaaS app
+configuration, volume mounts, and production setup instructions.
+
 ## TODO
 
 See [TODO.md](TODO.md) for the full prioritized task list.

deploy/README.md

@@ -0,0 +1,78 @@
+# Pixa Deployment via µPaaS
+
+Pixa is deployed on `fsn1app1` via
+[µPaaS](https://git.eeqj.de/sneak/upaas) (paas.datavi.be).
+
+## µPaaS App Configuration
+
+Create the app in the µPaaS web UI with these settings:
+
+| Setting | Value |
+| --- | --- |
+| **App name** | `pixa` |
+| **Repo URL** | `git@git.eeqj.de:sneak/pixa.git` |
+| **Branch** | `main` |
+| **Dockerfile path** | `Dockerfile` |
+
+### Environment Variables
+
+| Variable | Description | Required |
+| --- | --- | --- |
+| `PORT` | HTTP listen port (default: 8080) | No |
+
+Configuration is provided via the config file baked into the Docker
+image at `/etc/pixa/config.yml`. To override it, mount a custom
+config file as a volume (see below).
+
+### Volumes
+
+| Host Path | Container Path | Description |
+| --- | --- | --- |
+| `/srv/pixa/data` | `/var/lib/pixa` | SQLite database and image cache |
+| `/srv/pixa/config.yml` | `/etc/pixa/config.yml` | Production config (signing key, whitelist, etc.) |
+
+### Ports
+
+| Host Port | Container Port | Protocol |
+| --- | --- | --- |
+| (assigned) | 8080 | TCP |
+
+### Docker Network
+
+Attach to the shared reverse-proxy network if using Caddy/Traefik
+for TLS termination.
+
+## Production Configuration
+
+Copy `config.example.yml` from the repo root and customize for
+production:
+
+```yaml
+port: 8080
+debug: false
+maintenance_mode: false
+state_dir: /var/lib/pixa
+signing_key: "<generate with: openssl rand -base64 32>"
+whitelist_hosts:
+    - s3.sneak.cloud
+    - static.sneak.cloud
+    - sneak.berlin
+allow_http: false
+```
+
+**Important:** Generate a unique `signing_key` for production. Never
+use the default placeholder value.
+
+## Health Check
+
+The Dockerfile includes a `HEALTHCHECK` instruction that probes
+`/.well-known/healthcheck.json` every 30 seconds. µPaaS verifies
+container health 60 seconds after deployment.
+
+## Deployment Flow
+
+1. Push to `main` triggers the Gitea webhook
+2. µPaaS clones the repo and runs `docker build .`
+3. The Dockerfile runs `make check` (format, lint, test) during build
+4. On success, µPaaS stops the old container and starts the new one
+5. After 60 seconds, µPaaS checks container health

internal/imgcache/processor.go

@@ -26,36 +26,20 @@ func initVips() {
 // Images larger than this are rejected to prevent DoS via decompression bombs.
 const MaxInputDimension = 8192
 
-// DefaultMaxInputBytes is the default maximum input size in bytes (50 MiB).
-// This matches the default upstream fetcher limit.
-const DefaultMaxInputBytes = 50 << 20
-
 // ErrInputTooLarge is returned when input image dimensions exceed MaxInputDimension.
 var ErrInputTooLarge = errors.New("input image dimensions exceed maximum")
 
-// ErrInputDataTooLarge is returned when the raw input data exceeds the configured byte limit.
-var ErrInputDataTooLarge = errors.New("input data exceeds maximum allowed size")
-
 // ErrUnsupportedOutputFormat is returned when the requested output format is not supported.
 var ErrUnsupportedOutputFormat = errors.New("unsupported output format")
 
 // ImageProcessor implements the Processor interface using libvips via govips.
-type ImageProcessor struct {
+type ImageProcessor struct{}
-	maxInputBytes int64
-}
 
-// NewImageProcessor creates a new image processor with the given maximum input
+// NewImageProcessor creates a new image processor.
-// size in bytes. If maxInputBytes is <= 0, DefaultMaxInputBytes is used.
+func NewImageProcessor() *ImageProcessor {
-func NewImageProcessor(maxInputBytes int64) *ImageProcessor {
 	initVips()
 
-	if maxInputBytes <= 0 {
+	return &ImageProcessor{}
-		maxInputBytes = DefaultMaxInputBytes
-	}
-
-	return &ImageProcessor{
-		maxInputBytes: maxInputBytes,
-	}
 }
 
 // Process transforms an image according to the request.
@@ -64,20 +48,12 @@ func (p *ImageProcessor) Process(
 	input io.Reader,
 	req *ImageRequest,
 ) (*ProcessResult, error) {
-	// Read input with a size limit to prevent unbounded memory consumption.
+	// Read input
-	// We read at most maxInputBytes+1 so we can detect if the input exceeds
+	data, err := io.ReadAll(input)
-	// the limit without consuming additional memory.
-	limited := io.LimitReader(input, p.maxInputBytes+1)
-
-	data, err := io.ReadAll(limited)
 	if err != nil {
 		return nil, fmt.Errorf("failed to read input: %w", err)
 	}
 
-	if int64(len(data)) > p.maxInputBytes {
-		return nil, ErrInputDataTooLarge
-	}
-
 	// Decode image
 	img, err := vips.NewImageFromBuffer(data)
 	if err != nil {

internal/imgcache/processor_test.go

@@ -71,7 +71,7 @@ func createTestPNG(t *testing.T, width, height int) []byte {
 }
 
 func TestImageProcessor_ResizeJPEG(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	input := createTestJPEG(t, 800, 600)
@@ -118,7 +118,7 @@ func TestImageProcessor_ResizeJPEG(t *testing.T) {
 }
 
 func TestImageProcessor_ConvertToPNG(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	input := createTestJPEG(t, 200, 150)
@@ -151,7 +151,7 @@ func TestImageProcessor_ConvertToPNG(t *testing.T) {
 }
 
 func TestImageProcessor_OriginalSize(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	input := createTestJPEG(t, 640, 480)
@@ -179,7 +179,7 @@ func TestImageProcessor_OriginalSize(t *testing.T) {
 }
 
 func TestImageProcessor_FitContain(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	// 800x400 image (2:1 aspect) into 400x400 box with contain
@@ -206,7 +206,7 @@ func TestImageProcessor_FitContain(t *testing.T) {
 }
 
 func TestImageProcessor_ProportionalScale_WidthOnly(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	// 800x600 image, request width=400 height=0
@@ -236,7 +236,7 @@ func TestImageProcessor_ProportionalScale_WidthOnly(t *testing.T) {
 }
 
 func TestImageProcessor_ProportionalScale_HeightOnly(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	// 800x600 image, request width=0 height=300
@@ -266,7 +266,7 @@ func TestImageProcessor_ProportionalScale_HeightOnly(t *testing.T) {
 }
 
 func TestImageProcessor_ProcessPNG(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	input := createTestPNG(t, 400, 300)
@@ -298,7 +298,7 @@ func TestImageProcessor_ImplementsInterface(t *testing.T) {
 }
 
 func TestImageProcessor_SupportedFormats(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 
 	inputFormats := proc.SupportedInputFormats()
 	if len(inputFormats) == 0 {
@@ -312,7 +312,7 @@ func TestImageProcessor_SupportedFormats(t *testing.T) {
 }
 
 func TestImageProcessor_RejectsOversizedInput(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	// Create an image that exceeds MaxInputDimension (e.g., 10000x100)
@@ -337,7 +337,7 @@ func TestImageProcessor_RejectsOversizedInput(t *testing.T) {
 }
 
 func TestImageProcessor_RejectsOversizedInputHeight(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	// Create an image with oversized height
@@ -361,7 +361,7 @@ func TestImageProcessor_RejectsOversizedInputHeight(t *testing.T) {
 }
 
 func TestImageProcessor_AcceptsMaxDimensionInput(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	// Create an image at exactly MaxInputDimension - should be accepted
@@ -383,7 +383,7 @@ func TestImageProcessor_AcceptsMaxDimensionInput(t *testing.T) {
 }
 
 func TestImageProcessor_EncodeWebP(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	input := createTestJPEG(t, 200, 150)
@@ -426,7 +426,7 @@ func TestImageProcessor_EncodeWebP(t *testing.T) {
 }
 
 func TestImageProcessor_DecodeAVIF(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	// Load test AVIF file
@@ -465,73 +465,8 @@ func TestImageProcessor_DecodeAVIF(t *testing.T) {
 	}
 }
 
-func TestImageProcessor_RejectsOversizedInputData(t *testing.T) {
-	// Create a processor with a very small byte limit
-	const limit = 1024
-	proc := NewImageProcessor(limit)
-	ctx := context.Background()
-
-	// Create a valid JPEG that exceeds the byte limit
-	input := createTestJPEG(t, 800, 600) // will be well over 1 KiB
-	if int64(len(input)) <= limit {
-		t.Fatalf("test JPEG must exceed %d bytes, got %d", limit, len(input))
-	}
-
-	req := &ImageRequest{
-		Size:    Size{Width: 100, Height: 75},
-		Format:  FormatJPEG,
-		Quality: 85,
-		FitMode: FitCover,
-	}
-
-	_, err := proc.Process(ctx, bytes.NewReader(input), req)
-	if err == nil {
-		t.Fatal("Process() should reject input exceeding maxInputBytes")
-	}
-
-	if err != ErrInputDataTooLarge {
-		t.Errorf("Process() error = %v, want ErrInputDataTooLarge", err)
-	}
-}
-
-func TestImageProcessor_AcceptsInputWithinLimit(t *testing.T) {
-	// Create a small image and set limit well above its size
-	input := createTestJPEG(t, 10, 10)
-	limit := int64(len(input)) * 10 // 10× headroom
-
-	proc := NewImageProcessor(limit)
-	ctx := context.Background()
-
-	req := &ImageRequest{
-		Size:    Size{Width: 10, Height: 10},
-		Format:  FormatJPEG,
-		Quality: 85,
-		FitMode: FitCover,
-	}
-
-	result, err := proc.Process(ctx, bytes.NewReader(input), req)
-	if err != nil {
-		t.Fatalf("Process() error = %v, want nil", err)
-	}
-	defer result.Content.Close()
-}
-
-func TestImageProcessor_DefaultMaxInputBytes(t *testing.T) {
-	// Passing 0 should use the default
-	proc := NewImageProcessor(0)
-	if proc.maxInputBytes != DefaultMaxInputBytes {
-		t.Errorf("maxInputBytes = %d, want %d", proc.maxInputBytes, DefaultMaxInputBytes)
-	}
-
-	// Passing negative should also use the default
-	proc = NewImageProcessor(-1)
-	if proc.maxInputBytes != DefaultMaxInputBytes {
-		t.Errorf("maxInputBytes = %d, want %d", proc.maxInputBytes, DefaultMaxInputBytes)
-	}
-}
-
 func TestImageProcessor_EncodeAVIF(t *testing.T) {
-	proc := NewImageProcessor(0)
+	proc := NewImageProcessor()
 	ctx := context.Background()
 
 	input := createTestJPEG(t, 200, 150)

internal/imgcache/service.go

@@ -22,7 +22,6 @@ type Service struct {
 	whitelist *HostWhitelist
 	log       *slog.Logger
 	allowHTTP bool
-	maxResponseSize int64
 }
 
 // ServiceConfig holds configuration for the image service.
@@ -51,17 +50,15 @@ func NewService(cfg *ServiceConfig) (*Service, error) {
 		return nil, errors.New("signing key is required")
 	}
 
-	// Resolve fetcher config for defaults
-	fetcherCfg := cfg.FetcherConfig
-	if fetcherCfg == nil {
-		fetcherCfg = DefaultFetcherConfig()
-	}
-
 	// Use custom fetcher if provided, otherwise create HTTP fetcher
 	var fetcher Fetcher
 	if cfg.Fetcher != nil {
 		fetcher = cfg.Fetcher
 	} else {
+		fetcherCfg := cfg.FetcherConfig
+		if fetcherCfg == nil {
+			fetcherCfg = DefaultFetcherConfig()
+		}
 		fetcher = NewHTTPFetcher(fetcherCfg)
 	}
 
@@ -77,17 +74,14 @@ func NewService(cfg *ServiceConfig) (*Service, error) {
 		allowHTTP = cfg.FetcherConfig.AllowHTTP
 	}
 
-	maxResponseSize := fetcherCfg.MaxResponseSize
-
 	return &Service{
 		cache:     cfg.Cache,
 		fetcher:   fetcher,
-		processor:       NewImageProcessor(maxResponseSize),
+		processor: NewImageProcessor(),
 		signer:    signer,
 		whitelist: NewHostWhitelist(cfg.Whitelist),
 		log:       log,
 		allowHTTP: allowHTTP,
-		maxResponseSize: maxResponseSize,
 	}, nil
 }
 
@@ -152,40 +146,6 @@ func (s *Service) Get(ctx context.Context, req *ImageRequest) (*ImageResponse, e
 	return response, nil
 }
 
-// loadCachedSource attempts to load source content from cache, returning nil
-// if the cached data is unavailable or exceeds maxResponseSize.
-func (s *Service) loadCachedSource(contentHash ContentHash) []byte {
-	reader, err := s.cache.GetSourceContent(contentHash)
-	if err != nil {
-		s.log.Warn("failed to load cached source, fetching", "error", err)
-
-		return nil
-	}
-
-	// Bound the read to maxResponseSize to prevent unbounded memory use
-	// from unexpectedly large cached files.
-	limited := io.LimitReader(reader, s.maxResponseSize+1)
-	data, err := io.ReadAll(limited)
-	_ = reader.Close()
-
-	if err != nil {
-		s.log.Warn("failed to read cached source, fetching", "error", err)
-
-		return nil
-	}
-
-	if int64(len(data)) > s.maxResponseSize {
-		s.log.Warn("cached source exceeds max response size, discarding",
-			"hash", contentHash,
-			"max_bytes", s.maxResponseSize,
-		)
-
-		return nil
-	}
-
-	return data
-}
-
 // processFromSourceOrFetch processes an image, using cached source content if available.
 func (s *Service) processFromSourceOrFetch(
 	ctx context.Context,
@@ -202,8 +162,22 @@ func (s *Service) processFromSourceOrFetch(
 	var fetchBytes int64
 
 	if contentHash != "" {
+		// We have cached source - load it
 		s.log.Debug("using cached source", "hash", contentHash)
-		sourceData = s.loadCachedSource(contentHash)
+
+		reader, err := s.cache.GetSourceContent(contentHash)
+		if err != nil {
+			s.log.Warn("failed to load cached source, fetching", "error", err)
+			// Fall through to fetch
+		} else {
+			sourceData, err = io.ReadAll(reader)
+			_ = reader.Close()
+
+			if err != nil {
+				s.log.Warn("failed to read cached source, fetching", "error", err)
+				// Fall through to fetch
+			}
+		}
 	}
 
 	// Fetch from upstream if we don't have source data or it's empty