feat: Remove geometry and properties from GET /datasets/{id} endpoint, new endpoint for download cog file

internal/domain/dataset.go

@@ -197,8 +197,8 @@ type Dataset struct {
 	SizeBytes     int64    `json:"size_bytes"`
 	ContentType   string   `json:"content_type"`
 	// Properties holds tabular data extracted from the file (e.g. a shapefile's
-	// attribute table). Nullable.
-	Properties json.RawMessage `json:"properties"`
+	// attribute table). Nullable; not exposed in dataset responses.
+	Properties json.RawMessage `json:"-"`
 	// Meta holds arbitrary user-defined data. Nullable.
 	Meta json.RawMessage `json:"meta"`
 	// Automated is a user-defined flag.
@@ -215,8 +215,9 @@ type Dataset struct {
 	// ParseError holds the failure reason when Status is failed. Nullable.
 	ParseError *string `json:"parse_error"`
 	// Geometry is the dataset's spatial geometry, serialized as GeoJSON.
-	// Nullable; populated from the file's spatial data.
-	Geometry json.RawMessage `json:"geometry"`
+	// Nullable; populated from the file's spatial data. Not exposed in dataset
+	// responses.
+	Geometry json.RawMessage `json:"-"`
 	// GeoJSON is the pre-assembled GeoJSON FeatureCollection served by the
 	// .geojson endpoint. It is generated and persisted at processing time for
 	// vector and vector_with_kato datasets. Nullable; not exposed on the dataset

internal/service/dataset.go

@@ -22,6 +22,15 @@ import (
 // maxParseBytes caps how much of a file is read into memory for parsing.
 const maxParseBytes = 256 << 20 // 256 MiB
 
+var (
+	// ErrNotRaster is returned when a raster-only operation is requested for a
+	// non-raster dataset.
+	ErrNotRaster = errors.New("dataset is not a raster")
+	// ErrCOGNotReady is returned when a raster's Cloud-Optimized GeoTIFF has not
+	// been produced yet.
+	ErrCOGNotReady = errors.New("cog is not ready")
+)
+
 // DatasetRepository is the persistence behaviour DatasetService needs.
 type DatasetRepository interface {
 	Create(ctx context.Context, d domain.Dataset) (domain.Dataset, error)
@@ -958,6 +967,27 @@ func (s *DatasetService) Download(ctx context.Context, id uuid.UUID) (domain.Dat
 	return dataset, obj, nil
 }
 
+// COG returns the dataset metadata and a reader for its Cloud-Optimized GeoTIFF.
+// It fails with ErrNotRaster for non-raster datasets and ErrCOGNotReady when the
+// raster has not been converted yet. The caller must close the reader.
+func (s *DatasetService) COG(ctx context.Context, id uuid.UUID) (domain.Dataset, io.ReadCloser, error) {
+	dataset, err := s.repo.GetByID(ctx, id)
+	if err != nil {
+		return domain.Dataset{}, nil, err
+	}
+	if dataset.FileType != domain.FileTypeRaster {
+		return domain.Dataset{}, nil, ErrNotRaster
+	}
+	if dataset.CogStorageKey == nil {
+		return domain.Dataset{}, nil, ErrCOGNotReady
+	}
+	obj, err := s.store.Get(ctx, *dataset.CogStorageKey)
+	if err != nil {
+		return domain.Dataset{}, nil, err
+	}
+	return dataset, obj, nil
+}
+
 // Delete removes the dataset row and its stored object.
 func (s *DatasetService) Delete(ctx context.Context, id uuid.UUID) error {
 	dataset, err := s.repo.GetByID(ctx, id)

internal/transport/http/dataset_handler.go

@@ -2,6 +2,7 @@ package http
 
 import (
 	"encoding/json"
+	"errors"
 	"io"
 	"net/http"
 	"strconv"
@@ -37,6 +38,7 @@ func (h *DatasetHandler) Register(r chi.Router) {
 	r.Post("/", h.upload)
 	r.Get("/{id}", h.get)
 	r.Get("/{id}.geojson", h.geojson)
+	r.Get("/{id}.cog", h.cog)
 	r.Get("/{id}/status", h.status)
 	r.Get("/{id}/download", h.download)
 	r.Post("/{id}/mapping", h.mapping)
@@ -324,6 +326,44 @@ func (h *DatasetHandler) geojson(w http.ResponseWriter, r *http.Request) {
 	_, _ = w.Write(fc)
 }
 
+// cog streams the raster dataset's Cloud-Optimized GeoTIFF. It responds 422 for
+// a non-raster dataset and 409 when the raster's COG has not been produced yet.
+func (h *DatasetHandler) cog(w http.ResponseWriter, r *http.Request) {
+	id, ok := parseUUIDParam(w, r, "id")
+	if !ok {
+		return
+	}
+	dataset, obj, err := h.svc.COG(r.Context(), id)
+	if err != nil {
+		switch {
+		case errors.Is(err, service.ErrNotRaster):
+			httputil.WriteError(w, http.StatusUnprocessableEntity, "dataset is not a raster")
+		case errors.Is(err, service.ErrCOGNotReady):
+			httputil.WriteError(w, http.StatusConflict, "cog is not ready")
+		default:
+			respondDomainError(w, err)
+		}
+		return
+	}
+	defer obj.Close()
+
+	w.Header().Set("Content-Type", "image/tiff")
+	w.Header().Set("Content-Disposition", `inline; filename="`+cogFilename(dataset.Filename)+`"`)
+	w.WriteHeader(http.StatusOK)
+	if _, err := io.Copy(w, obj); err != nil {
+		// Headers are already sent; nothing useful to return to the client.
+		return
+	}
+}
+
+// cogFilename derives a .cog.tif download name from the source filename.
+func cogFilename(filename string) string {
+	if i := strings.LastIndex(filename, "."); i > 0 {
+		filename = filename[:i]
+	}
+	return filename + ".cog.tif"
+}
+
 func (h *DatasetHandler) download(w http.ResponseWriter, r *http.Request) {
 	id, ok := parseUUIDParam(w, r, "id")
 	if !ok {