feat(api): GET /api/albums/{id}/cover with sidecar fallback

2026-04-21 22:37:53 -04:00
parent 5af6d7fac6
commit 945b773cbd
3 changed files with 192 additions and 0 deletions
@@ -18,6 +18,7 @@ func newLibraryRouter(h *handlers) chi.Router {
 	r.Get("/api/artists", h.handleListArtists)
 	r.Get("/api/artists/{id}", h.handleGetArtist)
 	r.Get("/api/albums/{id}", h.handleGetAlbum)
+	r.Get("/api/albums/{id}/cover", h.handleGetCover)
 	r.Get("/api/tracks/{id}", h.handleGetTrack)
 	r.Get("/api/search", h.handleSearch)
 	return r
@@ -8,10 +8,15 @@ package api

 import (
 	"context"
+	"errors"
+	"net/http"
 	"os"
 	"path/filepath"
 	"strings"

+	"github.com/go-chi/chi/v5"
+	"github.com/jackc/pgx/v5"
+
 	"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
 )

@@ -96,3 +101,49 @@ func imageContentType(path string) string {
 	}
 	return "application/octet-stream"
 }
+
+// handleGetCover implements GET /api/albums/{id}/cover. Resolves the cover
+// path (explicit column, else sidecar next to first track), then delegates
+// byte-serving to http.ServeContent so clients get Range / If-Modified-Since
+// / ETag for free.
+func (h *handlers) handleGetCover(w http.ResponseWriter, r *http.Request) {
+	id, ok := parseUUID(chi.URLParam(r, "id"))
+	if !ok {
+		writeErr(w, http.StatusBadRequest, "bad_request", "invalid album id")
+		return
+	}
+	q := dbq.New(h.pool)
+	album, err := q.GetAlbumByID(r.Context(), id)
+	if err != nil {
+		if errors.Is(err, pgx.ErrNoRows) {
+			writeErr(w, http.StatusNotFound, "not_found", "album not found")
+			return
+		}
+		h.logger.Error("api: get album for cover failed", "err", err)
+		writeErr(w, http.StatusInternalServerError, "server_error", "server error")
+		return
+	}
+	path := resolveAlbumCoverPath(r.Context(), q, album)
+	if path == "" {
+		writeErr(w, http.StatusNotFound, "not_found", "cover not found")
+		return
+	}
+	f, err := os.Open(path)
+	if err != nil {
+		// resolveAlbumCoverPath saw the file a moment ago; if it vanished
+		// between stat and open, treat it the same as no-art — the user
+		// experience (404) matches, and 500 would misleadingly imply a server
+		// bug rather than a filesystem race.
+		writeErr(w, http.StatusNotFound, "not_found", "cover not found")
+		return
+	}
+	defer func() { _ = f.Close() }()
+	info, err := f.Stat()
+	if err != nil {
+		h.logger.Error("api: stat cover failed", "err", err)
+		writeErr(w, http.StatusInternalServerError, "server_error", "server error")
+		return
+	}
+	w.Header().Set("Content-Type", imageContentType(path))
+	http.ServeContent(w, r, filepath.Base(path), info.ModTime(), f)
+}
@@ -1,7 +1,11 @@
 package api

 import (
+	"bytes"
 	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
 	"os"
 	"path/filepath"
 	"testing"
@@ -147,3 +151,139 @@ func fetchAlbum(t *testing.T, pool *pgxpool.Pool, id pgtype.UUID) dbq.Album {
 	}
 	return a
 }
+
+func TestHandleGetCover_SidecarHappyPath(t *testing.T) {
+	h, pool := testHandlers(t)
+	truncateLibrary(t, pool)
+	artist := seedArtist(t, pool, "A")
+	album := seedAlbum(t, pool, artist.ID, "X", 0)
+
+	_, dir := seedTrackWithFile(t, pool, album.ID, artist.ID, "t", []byte("audio"), "mp3")
+	coverBytes := []byte{0xFF, 0xD8, 0xFF, 0xE0, 0x01, 0x02, 0x03} // small JPEG-ish payload
+	if err := os.WriteFile(filepath.Join(dir, "cover.jpg"), coverBytes, 0o644); err != nil {
+		t.Fatal(err)
+	}
+
+	req := httptest.NewRequest(http.MethodGet, "/api/albums/"+uuidToString(album.ID)+"/cover", nil)
+	w := httptest.NewRecorder()
+	newLibraryRouter(h).ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("status = %d body = %s", w.Code, w.Body.String())
+	}
+	if ct := w.Header().Get("Content-Type"); ct != "image/jpeg" {
+		t.Errorf("Content-Type = %q", ct)
+	}
+	if !bytes.Equal(w.Body.Bytes(), coverBytes) {
+		t.Errorf("body = %x, want %x", w.Body.Bytes(), coverBytes)
+	}
+}
+
+func TestHandleGetCover_ExplicitPathHappyPath(t *testing.T) {
+	h, pool := testHandlers(t)
+	truncateLibrary(t, pool)
+	artist := seedArtist(t, pool, "A")
+	album := seedAlbum(t, pool, artist.ID, "X", 0)
+
+	dir := t.TempDir()
+	explicit := filepath.Join(dir, "art.png")
+	pngBytes := []byte{0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A} // PNG magic
+	if err := os.WriteFile(explicit, pngBytes, 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := pool.Exec(context.Background(),
+		`UPDATE albums SET cover_art_path = $1 WHERE id = $2`, explicit, album.ID); err != nil {
+		t.Fatal(err)
+	}
+
+	req := httptest.NewRequest(http.MethodGet, "/api/albums/"+uuidToString(album.ID)+"/cover", nil)
+	w := httptest.NewRecorder()
+	newLibraryRouter(h).ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("status = %d body = %s", w.Code, w.Body.String())
+	}
+	if ct := w.Header().Get("Content-Type"); ct != "image/png" {
+		t.Errorf("Content-Type = %q", ct)
+	}
+	if !bytes.Equal(w.Body.Bytes(), pngBytes) {
+		t.Errorf("body mismatch")
+	}
+}
+
+func TestHandleGetCover_ExplicitMissingFallsThroughToSidecar(t *testing.T) {
+	h, pool := testHandlers(t)
+	truncateLibrary(t, pool)
+	artist := seedArtist(t, pool, "A")
+	album := seedAlbum(t, pool, artist.ID, "X", 0)
+
+	_, dir := seedTrackWithFile(t, pool, album.ID, artist.ID, "t", []byte("audio"), "mp3")
+	sidecarBytes := []byte("sidecar")
+	if err := os.WriteFile(filepath.Join(dir, "cover.jpg"), sidecarBytes, 0o644); err != nil {
+		t.Fatal(err)
+	}
+	if _, err := pool.Exec(context.Background(),
+		`UPDATE albums SET cover_art_path = $1 WHERE id = $2`,
+		filepath.Join(dir, "does-not-exist.jpg"), album.ID); err != nil {
+		t.Fatal(err)
+	}
+
+	req := httptest.NewRequest(http.MethodGet, "/api/albums/"+uuidToString(album.ID)+"/cover", nil)
+	w := httptest.NewRecorder()
+	newLibraryRouter(h).ServeHTTP(w, req)
+
+	if w.Code != http.StatusOK {
+		t.Fatalf("status = %d", w.Code)
+	}
+	if !bytes.Equal(w.Body.Bytes(), sidecarBytes) {
+		t.Errorf("body = %q, want %q", w.Body.Bytes(), sidecarBytes)
+	}
+}
+
+func TestHandleGetCover_NoArt(t *testing.T) {
+	h, pool := testHandlers(t)
+	truncateLibrary(t, pool)
+	artist := seedArtist(t, pool, "A")
+	album := seedAlbum(t, pool, artist.ID, "X", 0)
+	seedTrack(t, pool, album.ID, artist.ID, "t", 1, 1000) // synthetic path, no sidecar
+
+	req := httptest.NewRequest(http.MethodGet, "/api/albums/"+uuidToString(album.ID)+"/cover", nil)
+	w := httptest.NewRecorder()
+	newLibraryRouter(h).ServeHTTP(w, req)
+
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("status = %d", w.Code)
+	}
+	var body errorBody
+	_ = json.Unmarshal(w.Body.Bytes(), &body)
+	if body.Error.Code != "not_found" || body.Error.Message != "cover not found" {
+		t.Errorf("error body = %+v", body)
+	}
+}
+
+func TestHandleGetCover_BadUUID(t *testing.T) {
+	h, _ := testHandlers(t)
+	req := httptest.NewRequest(http.MethodGet, "/api/albums/not-a-uuid/cover", nil)
+	w := httptest.NewRecorder()
+	newLibraryRouter(h).ServeHTTP(w, req)
+	if w.Code != http.StatusBadRequest {
+		t.Errorf("status = %d, want 400", w.Code)
+	}
+}
+
+func TestHandleGetCover_UnknownAlbum(t *testing.T) {
+	h, pool := testHandlers(t)
+	truncateLibrary(t, pool)
+	req := httptest.NewRequest(http.MethodGet,
+		"/api/albums/00000000-0000-0000-0000-000000000001/cover", nil)
+	w := httptest.NewRecorder()
+	newLibraryRouter(h).ServeHTTP(w, req)
+	if w.Code != http.StatusNotFound {
+		t.Fatalf("status = %d", w.Code)
+	}
+	var body errorBody
+	_ = json.Unmarshal(w.Body.Bytes(), &body)
+	if body.Error.Message != "album not found" {
+		t.Errorf("message = %q, want \"album not found\"", body.Error.Message)
+	}
+}