Initial QSfera import

Server/services/thumbnails/pkg/service/http/v0/service.go

@@ -0,0 +1,150 @@
+package svc
+
+import (
+	"context"
+	"fmt"
+	"net/http"
+	"strconv"
+
+	"github.com/go-chi/chi/v5"
+	"github.com/golang-jwt/jwt/v5"
+	"github.com/riandyrn/otelchi"
+
+	"github.com/qsfera/server/pkg/log"
+	"github.com/qsfera/server/pkg/tracing"
+	"github.com/qsfera/server/services/thumbnails/pkg/config"
+	tjwt "github.com/qsfera/server/services/thumbnails/pkg/service/jwt"
+	"github.com/qsfera/server/services/thumbnails/pkg/thumbnail"
+)
+
+type contextKey string
+
+const (
+	keyContextKey contextKey = "key"
+)
+
+// Service defines the service handlers.
+type Service interface {
+	ServeHTTP(w http.ResponseWriter, r *http.Request)
+	GetThumbnail(w http.ResponseWriter, r *http.Request)
+}
+
+// NewService returns a service implementation for Service.
+func NewService(opts ...Option) Service {
+	options := newOptions(opts...)
+
+	m := chi.NewMux()
+	m.Use(options.Middleware...)
+
+	m.Use(
+		otelchi.Middleware(
+			"thumbnails",
+			otelchi.WithChiRoutes(m),
+			otelchi.WithTracerProvider(options.TraceProvider),
+			otelchi.WithPropagators(tracing.GetPropagator()),
+		),
+	)
+
+	logger := options.Logger
+	resolutions, err := thumbnail.ParseResolutions(options.Config.Thumbnail.Resolutions)
+	if err != nil {
+		logger.Fatal().Err(err).Msg("resolutions not configured correctly")
+	}
+	svc := Thumbnails{
+		config: options.Config,
+		mux:    m,
+		logger: options.Logger,
+		manager: thumbnail.NewSimpleManager(
+			resolutions,
+			options.ThumbnailStorage,
+			logger,
+			options.Config.Thumbnail.MaxInputWidth,
+			options.Config.Thumbnail.MaxInputHeight,
+		),
+	}
+
+	m.Route(options.Config.HTTP.Root, func(r chi.Router) {
+		r.Use(svc.TransferTokenValidator)
+		r.Get("/data", svc.GetThumbnail)
+	})
+
+	_ = chi.Walk(m, func(method string, route string, _ http.Handler, middlewares ...func(http.Handler) http.Handler) error {
+		options.Logger.Debug().Str("method", method).Str("route", route).Int("middlewares", len(middlewares)).Msg("serving endpoint")
+		return nil
+	})
+
+	return svc
+}
+
+// Thumbnails implements the business logic for Service.
+type Thumbnails struct {
+	config  *config.Config
+	logger  log.Logger
+	mux     *chi.Mux
+	manager thumbnail.Manager
+}
+
+// ServeHTTP implements the Service interface.
+func (s Thumbnails) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	s.mux.ServeHTTP(w, r)
+}
+
+// GetThumbnail implements the Service interface.
+func (s Thumbnails) GetThumbnail(w http.ResponseWriter, r *http.Request) {
+	logger := s.logger.SubloggerWithRequestID(r.Context())
+	key := r.Context().Value(keyContextKey).(string)
+
+	thumbnailBytes, err := s.manager.GetThumbnail(key)
+	if err != nil {
+		logger.Debug().
+			Err(err).
+			Str("key", key).
+			Msg("could not get the thumbnail")
+		w.WriteHeader(http.StatusInternalServerError)
+		return
+	}
+
+	w.WriteHeader(http.StatusOK)
+	w.Header().Set("Content-Length", strconv.Itoa(len(thumbnailBytes)))
+	if _, err = w.Write(thumbnailBytes); err != nil {
+		logger.Error().
+			Err(err).
+			Str("key", key).
+			Msg("could not write the thumbnail response")
+	}
+}
+
+// TransferTokenValidator validates a transfer token
+func (s Thumbnails) TransferTokenValidator(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		tokenString := r.Header.Get("Transfer-Token")
+		if tokenString == "" {
+			next.ServeHTTP(w, r)
+			return
+		}
+
+		logger := s.logger.SubloggerWithRequestID(r.Context())
+		token, err := jwt.ParseWithClaims(tokenString, &tjwt.ThumbnailClaims{}, func(token *jwt.Token) (any, error) {
+			if _, ok := token.Method.(*jwt.SigningMethodHMAC); !ok {
+				return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
+			}
+			return []byte(s.config.Thumbnail.TransferSecret), nil
+		})
+		if err != nil {
+			logger.Debug().
+				Err(err).
+				Str("transfer-token", tokenString).
+				Msg("failed to parse transfer token")
+			w.WriteHeader(http.StatusUnauthorized)
+			return
+		}
+
+		if claims, ok := token.Claims.(*tjwt.ThumbnailClaims); ok && token.Valid {
+			ctx := context.WithValue(r.Context(), keyContextKey, claims.Key)
+			next.ServeHTTP(w, r.WithContext(ctx))
+			return
+		}
+		logger.Debug().Msg("invalid transfer token")
+		w.WriteHeader(http.StatusUnauthorized)
+	})
+}