feat(rendering): support image legacy d-solo render mode, close #750 (#751)

Author: leoswing

tools/rendering.go

@@ -174,12 +174,18 @@ func buildRenderURL(baseURL string, args GetPanelImageParams) (string, error) {
 	// Strip trailing slashes from base URL for consistent URL construction
 	baseURL = strings.TrimRight(baseURL, "/")
 
-	// Build the render path
-	renderPath := fmt.Sprintf("/render/d/%s", args.DashboardUID)
-
 	// Build query parameters
 	params := url.Values{}
 
+	// Single-panel renders use the purpose-built /d-solo route (lighter than loading
+	// the full dashboard with viewPanel). Full dashboard renders use /d as default.
+	renderPath := fmt.Sprintf("/render/d/%s", args.DashboardUID)
+
+	if args.PanelID != nil {
+		renderPath = fmt.Sprintf("/render/d-solo/%s", args.DashboardUID)
+		params.Set("panelId", strconv.Itoa(*args.PanelID))
+	}
+
 	// Set dimensions
 	width := 1000
 	height := 500
@@ -199,11 +205,6 @@ func buildRenderURL(baseURL string, args GetPanelImageParams) (string, error) {
 	}
 	params.Set("scale", strconv.Itoa(scale))
 
-	// Add panel ID if specified (for single panel rendering)
-	if args.PanelID != nil {
-		params.Set("viewPanel", strconv.Itoa(*args.PanelID))
-	}
-
 	// Add time range
 	if args.TimeRange != nil {
 		if args.TimeRange.From != "" {

tools/rendering_test.go

@@ -148,10 +148,11 @@ func TestGetPanelImageParams_UnmarshalVariables(t *testing.T) {
 
 func TestBuildRenderURL(t *testing.T) {
 	tests := []struct {
-		name     string
-		baseURL  string
-		args     GetPanelImageParams
-		contains []string
+		name        string
+		baseURL     string
+		args        GetPanelImageParams
+		contains    []string
+		notContains []string
 	}{
 		{
 			name:    "Basic dashboard render",
@@ -168,7 +169,7 @@ func TestBuildRenderURL(t *testing.T) {
 			},
 		},
 		{
-			name:    "Panel render with custom dimensions",
+			name:    "Panel render with custom dimensions uses d-solo path",
 			baseURL: "http://localhost:3000",
 			args: GetPanelImageParams{
 				DashboardUID: "abc123",
@@ -177,11 +178,15 @@ func TestBuildRenderURL(t *testing.T) {
 				Height:       intPtr(600),
 			},
 			contains: []string{
-				"http://localhost:3000/render/d/abc123",
-				"viewPanel=5",
+				"http://localhost:3000/render/d-solo/abc123",
+				"panelId=5",
 				"width=800",
 				"height=600",
 			},
+			notContains: []string{
+				"/render/d/abc123",
+				"viewPanel=",
+			},
 		},
 		{
 			name:    "With time range",
@@ -269,6 +274,9 @@ func TestBuildRenderURL(t *testing.T) {
 			for _, expected := range tt.contains {
 				assert.Contains(t, result, expected)
 			}
+			for _, unexpected := range tt.notContains {
+				assert.NotContains(t, result, unexpected)
+			}
 		})
 	}
 }
@@ -328,9 +336,10 @@ func TestGetPanelImage(t *testing.T) {
 		}
 	})
 
-	t.Run("Panel image with specific panel ID", func(t *testing.T) {
+	t.Run("Panel image with specific panel ID uses d-solo path and panelId param", func(t *testing.T) {
 		server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			assert.Equal(t, "5", r.URL.Query().Get("viewPanel"))
+			assert.Contains(t, r.URL.Path, "/render/d-solo/test-dash")
+			assert.Equal(t, "5", r.URL.Query().Get("panelId"))
 
 			w.Header().Set("Content-Type", "image/png")
 			w.WriteHeader(http.StatusOK)