feat: expose learning video health detail

cmd/server/main.go

@@ -79,7 +79,7 @@ func main() {
 			"portal_url_set", cfg.PortalURL != "", "portal_key_set", cfg.InternalAPIKey != "")
 	}
 
-	healthH := handler.NewHealthHandler(pool)
+	healthH := handler.NewHealthHandler(pool, store)
 	testH := handler.NewTestHandler(testRepo, accessRepo)
 	attemptH := handler.NewAttemptHandler(attemptRepo, testRepo)
 	courseH := handler.NewCourseHandler(courseRepo, accessRepo)
@@ -94,6 +94,7 @@ func main() {
 
 	r.Get("/healthz", healthH.Healthz)
 	r.Get("/readyz", healthH.Readyz)
+	r.Get("/health/detail", healthH.Detail)
 
 	r.Route("/api", func(r chi.Router) {
 		r.Use(commonmw.InternalAuth(cfg.InternalAPIKey))

internal/handler/health.go

@@ -3,17 +3,21 @@ package handler
 import (
 	"context"
 	"net/http"
+	"strconv"
 	"time"
 
 	"github.com/jackc/pgx/v5/pgxpool"
+
+	"learning-service/internal/storage"
 )
 
 type HealthHandler struct {
-	pool *pgxpool.Pool
+	pool  *pgxpool.Pool
+	store *storage.Storage
 }
 
-func NewHealthHandler(pool *pgxpool.Pool) *HealthHandler {
+func NewHealthHandler(pool *pgxpool.Pool, store *storage.Storage) *HealthHandler {
-	return &HealthHandler{pool: pool}
+	return &HealthHandler{pool: pool, store: store}
 }
 
 // Healthz — liveness. Не дёргает БД; жив если процесс отвечает.
@@ -32,3 +36,65 @@ func (h *HealthHandler) Readyz(w http.ResponseWriter, r *http.Request) {
 	}
 	writeJSON(w, http.StatusOK, map[string]string{"status": "ready"})
 }
+
+func (h *HealthHandler) Detail(w http.ResponseWriter, r *http.Request) {
+	ctx, cancel := context.WithTimeout(r.Context(), 3*time.Second)
+	defer cancel()
+
+	components := []componentProbe{
+		h.probePostgres(ctx),
+		h.probeVideoStorage(ctx),
+		h.probeVideoMetadata(ctx),
+	}
+	writeJSON(w, http.StatusOK, map[string]any{"components": components})
+}
+
+type componentProbe struct {
+	Name      string `json:"name"`
+	Status    string `json:"status"`
+	LatencyMs int64  `json:"latency_ms"`
+	Error     string `json:"error,omitempty"`
+}
+
+func (h *HealthHandler) probePostgres(ctx context.Context) componentProbe {
+	start := time.Now()
+	if err := h.pool.Ping(ctx); err != nil {
+		return componentProbe{Name: "postgres", Status: "down", LatencyMs: time.Since(start).Milliseconds(), Error: err.Error()}
+	}
+	return componentProbe{Name: "postgres", Status: "ok", LatencyMs: time.Since(start).Milliseconds()}
+}
+
+func (h *HealthHandler) probeVideoStorage(ctx context.Context) componentProbe {
+	start := time.Now()
+	if err := h.store.Check(ctx); err != nil {
+		return componentProbe{Name: "video_storage", Status: "down", LatencyMs: time.Since(start).Milliseconds(), Error: err.Error()}
+	}
+	return componentProbe{Name: "video_storage", Status: "ok", LatencyMs: time.Since(start).Milliseconds()}
+}
+
+func (h *HealthHandler) probeVideoMetadata(ctx context.Context) componentProbe {
+	start := time.Now()
+	var videos, broken int
+	err := h.pool.QueryRow(ctx, `
+		SELECT
+			COUNT(*) FILTER (WHERE video_key <> '')::int,
+			COUNT(*) FILTER (WHERE video_key <> '' AND btrim(video_key) = '')::int
+		FROM lessons`,
+	).Scan(&videos, &broken)
+	if err != nil {
+		return componentProbe{Name: "video_metadata", Status: "down", LatencyMs: time.Since(start).Milliseconds(), Error: err.Error()}
+	}
+	if broken > 0 {
+		return componentProbe{
+			Name:      "video_metadata",
+			Status:    "down",
+			LatencyMs: time.Since(start).Milliseconds(),
+			Error:     "videos=" + intString(videos) + " broken_video_keys=" + intString(broken),
+		}
+	}
+	return componentProbe{Name: "video_metadata", Status: "ok", LatencyMs: time.Since(start).Milliseconds()}
+}
+
+func intString(v int) string {
+	return strconv.Itoa(v)
+}

internal/storage/minio.go

@@ -72,6 +72,20 @@ func (s *Storage) EnsureBucket(ctx context.Context) error {
 	return s.client.MakeBucket(ctx, s.cfg.Bucket, minio.MakeBucketOptions{})
 }
 
+func (s *Storage) Check(ctx context.Context) error {
+	if !s.Configured() {
+		return errors.New("storage not configured")
+	}
+	exists, err := s.client.BucketExists(ctx, s.cfg.Bucket)
+	if err != nil {
+		return fmt.Errorf("check bucket: %w", err)
+	}
+	if !exists {
+		return fmt.Errorf("bucket not found: %s", s.cfg.Bucket)
+	}
+	return nil
+}
+
 // GenerateKey — путь объекта в bucket'е. Структура: <lesson_id>/<random>.<ext>,
 // где random — короткий uuid для anti-cache + защита от перезаписи случайно.
 // При замене видео ставится новый key, старый объект остаётся в MinIO