Photo cache and /media endpoint (#68)

Co-authored-by: dev_agent <dev_agent@cubecraftlabs.com>

internal/server/login_test.go

@@ -83,7 +83,7 @@ func newLoginRouter(t *testing.T, issuer string) http.Handler {
 		t.Fatal(err)
 	}
 	r, err := NewRouter(logger, "dev", trusted, flow, sessions, newTestSettings(t),
-		newTestRunner(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
+		newTestRunner(t), newTestPhotos(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
 	if err != nil {
 		t.Fatal(err)
 	}

internal/server/media.go

@@ -0,0 +1,75 @@
+package server
+
+import (
+	"context"
+	"errors"
+	"io/fs"
+	"log/slog"
+	"net/http"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/go-chi/chi/v5"
+)
+
+// photoCacheControl lets the browser keep a photo for a year without
+// revalidating: a photo's files never change once stored, and a new image
+// gets a new id.
+const photoCacheControl = "private, max-age=31536000, immutable"
+
+// PhotoFiles opens a cached photo's file at one of its stored sizes. An
+// unknown photo or size is an error matching fs.ErrNotExist.
+type PhotoFiles interface {
+	OpenPhoto(ctx context.Context, id string, size int) (*os.File, error)
+}
+
+// getPhoto answers GET /media/photos/{id}-{size}.jpg with the stored JPEG.
+func getPhoto(logger *slog.Logger, photos PhotoFiles) http.HandlerFunc {
+	notFound := apiErrorHandler(logger, http.StatusNotFound, "not_found", "not found")
+	return func(w http.ResponseWriter, r *http.Request) {
+		id, size, ok := parsePhotoName(chi.URLParam(r, "name"))
+		if !ok {
+			notFound(w, r)
+			return
+		}
+		f, err := photos.OpenPhoto(r.Context(), id, size)
+		if errors.Is(err, fs.ErrNotExist) {
+			notFound(w, r)
+			return
+		}
+		if err != nil {
+			logger.ErrorContext(r.Context(), "open photo", "id", id, "size", size, "error", err)
+			writeError(w, r, logger, http.StatusInternalServerError, "internal", "internal error")
+			return
+		}
+		defer f.Close()
+		info, err := f.Stat()
+		if err != nil {
+			logger.ErrorContext(r.Context(), "stat photo", "id", id, "size", size, "error", err)
+			writeError(w, r, logger, http.StatusInternalServerError, "internal", "internal error")
+			return
+		}
+		w.Header().Set("Content-Type", "image/jpeg")
+		w.Header().Set("Cache-Control", photoCacheControl)
+		http.ServeContent(w, r, "", info.ModTime(), f)
+	}
+}
+
+// parsePhotoName splits "{id}-{size}.jpg" into its id and size, refusing
+// a size not written in its canonical decimal form.
+func parsePhotoName(name string) (id string, size int, ok bool) {
+	stem, ok := strings.CutSuffix(name, ".jpg")
+	if !ok {
+		return "", 0, false
+	}
+	i := strings.LastIndexByte(stem, '-')
+	if i < 0 {
+		return "", 0, false
+	}
+	size, err := strconv.Atoi(stem[i+1:])
+	if err != nil || strconv.Itoa(size) != stem[i+1:] {
+		return "", 0, false
+	}
+	return stem[:i], size, true
+}

internal/server/media_test.go

@@ -0,0 +1,138 @@
+package server
+
+import (
+	"io"
+	"log/slog"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"testing"
+	"testing/fstest"
+
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/db"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/recipes"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
+)
+
+// newMediaRouter returns a router over a photo cache whose data directory
+// holds both sizes of two photos, the id of the one with a photos row, and
+// the id of the orphan without one. Each size's file holds its size as
+// text.
+func newMediaRouter(t *testing.T) (r http.Handler, id, orphan string) {
+	t.Helper()
+	dataDir := t.TempDir()
+	st := newTestStore(t)
+	photos, err := recipes.NewPhotoCache(recipes.NewFetcher(), st, dataDir)
+	if err != nil {
+		t.Fatal(err)
+	}
+	id, orphan = store.NewID(), store.NewID()
+	for _, stem := range []string{id, orphan} {
+		for _, size := range []string{"400", "1200"} {
+			p := filepath.Join(dataDir, "media", "photos", stem+"-"+size+".jpg")
+			if err := os.WriteFile(p, []byte("jpeg "+size), 0o600); err != nil {
+				t.Fatal(err)
+			}
+		}
+	}
+	now := store.Now().String()
+	if _, err := db.New(st.Writer).CreatePhoto(t.Context(), db.CreatePhotoParams{
+		ID:        id,
+		SourceUrl: "https://example.com/a.jpg",
+		LocalPath: "media/photos/" + id + "-1200.jpg",
+		Width:     1600,
+		Height:    1200,
+		Sha256:    "sha",
+		FetchedAt: now,
+		CreatedAt: now,
+		UpdatedAt: now,
+	}); err != nil {
+		t.Fatal(err)
+	}
+	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
+	r, err = NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, newTestSettings(t), newTestRunner(t),
+		photos, fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
+	if err != nil {
+		t.Fatal(err)
+	}
+	return r, id, orphan
+}
+
+func TestGetPhotoServesEachSize(t *testing.T) {
+	t.Parallel()
+	router, id, _ := newMediaRouter(t)
+	for _, size := range []string{"400", "1200"} {
+		req := httptest.NewRequest(http.MethodGet, "/media/photos/"+id+"-"+size+".jpg", nil)
+		req.AddCookie(validSessionCookie)
+		rec := httptest.NewRecorder()
+		router.ServeHTTP(rec, req)
+
+		if rec.Code != http.StatusOK {
+			t.Fatalf("size %s: status = %d, want 200", size, rec.Code)
+		}
+		if got := rec.Body.String(); got != "jpeg "+size {
+			t.Errorf("size %s: body = %q", size, got)
+		}
+		if got := rec.Header().Get("Content-Type"); got != "image/jpeg" {
+			t.Errorf("size %s: Content-Type = %q, want image/jpeg", size, got)
+		}
+		if got := rec.Header().Get("Cache-Control"); got != "private, max-age=31536000, immutable" {
+			t.Errorf("size %s: Cache-Control = %q", size, got)
+		}
+	}
+}
+
+func TestGetPhotoRequiresSession(t *testing.T) {
+	t.Parallel()
+	router, id, _ := newMediaRouter(t)
+	req := httptest.NewRequest(http.MethodGet, "/media/photos/"+id+"-400.jpg", nil)
+	rec := httptest.NewRecorder()
+	router.ServeHTTP(rec, req)
+
+	if rec.Code != http.StatusUnauthorized {
+		t.Fatalf("status = %d, want 401", rec.Code)
+	}
+	if got := rec.Body.String(); got != unauthenticatedJSON {
+		t.Errorf("body = %s, want %s", got, unauthenticatedJSON)
+	}
+	if got := rec.Header().Get("Cache-Control"); got != "" {
+		t.Errorf("Cache-Control = %q on a refused request", got)
+	}
+}
+
+func TestGetPhotoUnknownNotFound(t *testing.T) {
+	t.Parallel()
+	router, id, orphan := newMediaRouter(t)
+	for _, name := range []string{
+		store.NewID() + "-400.jpg", // no such photo
+		orphan + "-400.jpg",        // file stored, no photos row
+		id + "-800.jpg",            // size not stored
+		orphan + "-1200.jpg",
+		id + "-0400.jpg",
+		id + "-+400.jpg",
+		id + "-400.png",
+		id + ".jpg",
+		id + "-400",
+		"..%2F" + id + "-400.jpg",
+		"not-an-id-400.jpg",
+	} {
+		t.Run(name, func(t *testing.T) {
+			t.Parallel()
+			req := httptest.NewRequest(http.MethodGet, "/media/photos/"+name, nil)
+			req.AddCookie(validSessionCookie)
+			rec := httptest.NewRecorder()
+			router.ServeHTTP(rec, req)
+
+			if rec.Code != http.StatusNotFound {
+				t.Fatalf("status = %d, want 404", rec.Code)
+			}
+			if got := rec.Body.String(); got != notFoundJSON {
+				t.Errorf("body = %s, want %s", got, notFoundJSON)
+			}
+			if got := rec.Header().Get("Cache-Control"); got != "" {
+				t.Errorf("Cache-Control = %q on a 404", got)
+			}
+		})
+	}
+}

internal/server/origin_test.go

@@ -45,7 +45,7 @@ func newOriginRouter(t *testing.T, logs io.Writer) http.Handler {
 	}
 	logger := slog.New(forwarded.LogHandler(slog.NewJSONHandler(logs, nil)))
 	r, err := NewRouter(logger, "dev", trusted, probeAuth{}, stubSessions{}, newTestSettings(t),
-		newTestRunner(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
+		newTestRunner(t), newTestPhotos(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
 	if err != nil {
 		t.Fatal(err)
 	}

internal/server/server.go

@@ -30,16 +30,20 @@ type RouteMounter interface {
 // only from a peer in trusted (see resolveOrigin). version is reported by
 // GET /health; auth mounts the /auth routes; sessions guards /api/v1 and
 // /media; settings serves /api/v1/settings/household; runner serves
-// POST /api/v1/jobs and GET /api/v1/jobs/{id}; assets is the web build
+// POST /api/v1/jobs and GET /api/v1/jobs/{id}; photos serves
+// GET /media/photos/{id}-{size}.jpg; assets is the web build
 // served for every other GET. /health, /auth and the web build are public.
 // Requests to /api/v1 other than GET also need the session's CSRF token in CSRFHeader.
-func NewRouter(logger *slog.Logger, version string, trusted forwarded.Trusted, auth RouteMounter, sessions SessionLookup, settings *household.SettingsService, runner *jobs.Runner, assets fs.FS) (http.Handler, error) {
+func NewRouter(logger *slog.Logger, version string, trusted forwarded.Trusted, auth RouteMounter, sessions SessionLookup, settings *household.SettingsService, runner *jobs.Runner, photos PhotoFiles, assets fs.FS) (http.Handler, error) {
 	if settings == nil {
 		return nil, errors.New("server: nil household settings service")
 	}
 	if runner == nil {
 		return nil, errors.New("server: nil job runner")
 	}
+	if photos == nil {
+		return nil, errors.New("server: nil photo files")
+	}
 	notFound := apiErrorHandler(logger, http.StatusNotFound, "not_found", "not found")
 	methodNotAllowed := apiErrorHandler(logger, http.StatusMethodNotAllowed, "method_not_allowed", "method not allowed")
 
@@ -70,6 +74,7 @@ func NewRouter(logger *slog.Logger, version string, trusted forwarded.Trusted, a
 	apiV1.Patch("/settings/household", patchHouseholdSettings(logger, settings))
 	apiV1.Post("/jobs", postJob(logger, runner))
 	apiV1.Get("/jobs/{id}", getJob(logger, runner))
+	media.Get("/photos/{name}", getPhoto(logger, photos))
 	r.Route("/api", func(r chi.Router) {
 		r.MethodNotAllowed(methodNotAllowed)
 		r.NotFound(notFound)

internal/server/server_test.go

@@ -16,6 +16,7 @@ import (
 
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/household"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/jobs"
+	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/recipes"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/internal/store"
 	"code.cubecraftlabs.com/Maniacs_Mansion/Meal-Quest/migrations"
 )
@@ -38,7 +39,7 @@ func newTestRouterWith(t *testing.T, version string, settings *household.Setting
 		"index.html":             {Data: []byte(fixtureIndex)},
 		"assets/index-AbC123.js": {Data: []byte(fixtureAsset)},
 	}
-	r, err := NewRouter(logger, version, nil, stubAuth{}, stubSessions{}, settings, runner, assets)
+	r, err := NewRouter(logger, version, nil, stubAuth{}, stubSessions{}, settings, runner, newTestPhotos(t), assets)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -112,11 +113,31 @@ func newTestRunner(t *testing.T) *jobs.Runner {
 	return runner
 }
 
+// newTestPhotos returns a photo cache over a migrated temp database and an
+// empty temp data directory.
+func newTestPhotos(t *testing.T) *recipes.PhotoCache {
+	t.Helper()
+	photos, err := recipes.NewPhotoCache(recipes.NewFetcher(), newTestStore(t), t.TempDir())
+	if err != nil {
+		t.Fatal(err)
+	}
+	return photos
+}
+
+func TestNewRouterRequiresPhotoFiles(t *testing.T) {
+	t.Parallel()
+
+	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
+	if _, err := NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, newTestSettings(t), newTestRunner(t), nil, fstest.MapFS{"index.html": {}}); err == nil {
+		t.Fatal("NewRouter accepted nil photo files")
+	}
+}
+
 func TestNewRouterRequiresSettings(t *testing.T) {
 	t.Parallel()
 
 	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
-	if _, err := NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, nil, newTestRunner(t), fstest.MapFS{"index.html": {}}); err == nil {
+	if _, err := NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, nil, newTestRunner(t), newTestPhotos(t), fstest.MapFS{"index.html": {}}); err == nil {
 		t.Fatal("NewRouter accepted a nil settings service")
 	}
 }
@@ -125,7 +146,7 @@ func TestNewRouterRequiresJobRunner(t *testing.T) {
 	t.Parallel()
 
 	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
-	if _, err := NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, newTestSettings(t), nil, fstest.MapFS{"index.html": {}}); err == nil {
+	if _, err := NewRouter(logger, "dev", nil, stubAuth{}, stubSessions{}, newTestSettings(t), nil, newTestPhotos(t), fstest.MapFS{"index.html": {}}); err == nil {
 		t.Fatal("NewRouter accepted a nil job runner")
 	}
 }

internal/server/settings_test.go

@@ -216,7 +216,7 @@ func TestHouseholdSettingsWithRealSession(t *testing.T) {
 	}
 	logger := slog.New(slog.NewTextHandler(io.Discard, nil))
 	router, err := NewRouter(logger, "dev", nil, stubAuth{}, sessions, household.NewSettingsService(st),
-		newTestRunner(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
+		newTestRunner(t), newTestPhotos(t), fstest.MapFS{"index.html": {Data: []byte(fixtureIndex)}})
 	if err != nil {
 		t.Fatal(err)
 	}