fix

Author: gsanchietti

api/routes.go

@@ -28,6 +28,9 @@ func RegisterRoutes(e *echo.Echo, svc *service.MessageService, pushSvc *service.
 	e.POST("/_matrix/push/v1/notify", h.matrixPushNotify)
 	// Matrix Application Service transactions (push events to AS)
 	e.PUT("/_matrix/app/v1/transactions/:txnId", h.matrixAppTransaction)
+
+	// Matrix Media Download Proxy
+	e.GET("/_matrix/media/v3/download/:serverName/:mediaId", h.proxyMediaDownload)
 }
 
 type handler struct {
@@ -229,3 +232,20 @@ func (h handler) matrixAppTransaction(c echo.Context) error {
 	// As per spec, acknowledge with an empty JSON object and 200 OK.
 	return c.JSON(http.StatusOK, map[string]interface{}{})
 }
+
+// proxyMediaDownload handles media download requests by proxying them to the Matrix homeserver.
+func (h handler) proxyMediaDownload(c echo.Context) error {
+	serverName := c.Param("serverName")
+	mediaId := c.Param("mediaId")
+	mxcURL := "mxc://" + serverName + "/" + mediaId
+
+	logger.Debug().Str("endpoint", "proxy_media_download").Str("mxc_url", mxcURL).Msg("proxying media download request")
+
+	data, contentType, err := h.svc.DownloadMedia(c.Request().Context(), mxcURL)
+	if err != nil {
+		logger.Error().Str("endpoint", "proxy_media_download").Str("mxc_url", mxcURL).Err(err).Msg("failed to download media from matrix")
+		return echo.NewHTTPError(http.StatusNotFound, "media not found")
+	}
+
+	return c.Blob(http.StatusOK, contentType, data)
+}

main_test.go

@@ -702,6 +702,30 @@ func TestIntegration_SendAndFetchImageMessages(t *testing.T) {
 				ft.Attachments[0].ContentSize,
 				ft.Attachments[0].Preview != nil)
 		})
+
+		// Step 4: Download the actual image from the proxy URL
+		t.Run("DownloadImageFromProxy", func(t *testing.T) {
+			resp, err := http.Get(attachment.ContentURL)
+			if err != nil {
+				t.Fatalf("failed to download image from proxy: %v", err)
+			}
+			defer resp.Body.Close()
+
+			if resp.StatusCode != http.StatusOK {
+				t.Errorf("expected status 200 OK, got %d", resp.StatusCode)
+			}
+
+			downloadedData, err := io.ReadAll(resp.Body)
+			if err != nil {
+				t.Fatalf("failed to read downloaded image data: %v", err)
+			}
+
+			if len(downloadedData) == 0 {
+				t.Errorf("downloaded image data is empty")
+			} else {
+				t.Logf("Image downloaded successfully from proxy: %d bytes", len(downloadedData))
+			}
+		})
 	})
 }
 

service/messages.go

@@ -898,3 +898,8 @@ func (s *MessageService) buildMediaURL(mxcURL string) string {
 
 	return publicURL
 }
+
+// DownloadMedia downloads media content from Matrix homeserver given an mxc:// URI.
+func (s *MessageService) DownloadMedia(ctx context.Context, mxcURL string) ([]byte, string, error) {
+	return s.matrixClient.DownloadMedia(ctx, mxcURL)
+}