Inject version info into index.html

cmd/query/app/fixture/index.html

@@ -4,4 +4,5 @@
     <base href="/" data-inject-target="BASE_URL"/>
     <title>Test Page</title>
     <!-- JAEGER_CONFIG=DEFAULT_CONFIG; -->
+    <!-- JAEGER_VERSION=DEFAULT_VERSION; -->
 </html>

cmd/query/app/static_handler.go

@@ -30,15 +30,17 @@ import (
 	"go.uber.org/zap"
 
 	"github.com/jaegertracing/jaeger/cmd/query/app/ui"
+	"github.com/jaegertracing/jaeger/pkg/version"
 )
 
 var (
 	favoriteIcon    = "favicon.ico"
 	staticRootFiles = []string{favoriteIcon}
+
+	// The following patterns are searched and replaced in the index.html as a way of customizing the UI.
 	configPattern   = regexp.MustCompile("JAEGER_CONFIG *= *DEFAULT_CONFIG;")
-	basePathPattern = regexp.MustCompile(`<base href="/"`)
-	basePathReplace = `<base href="%s/"`
-	errBadBasePath  = "Invalid base path '%s'. Must start but not end with a slash '/', e.g. '/jaeger/ui'"
+	versionPattern  = regexp.MustCompile("JAEGER_VERSION *= *DEFAULT_VERSION;")
+	basePathPattern = regexp.MustCompile(`<base href="/"`) // Note: tag is not closed
 )
 
 // RegisterStaticHandler adds handler for static assets to the router.
@@ -81,7 +83,7 @@ func NewStaticAssetsHandler(staticAssetsRoot string, options StaticAssetsHandler
 		options.Logger = zap.NewNop()
 	}
 
-	indexHTML, err := loadIndexBytes(assetsFS.Open, options)
+	indexHTML, err := loadAndEnrichIndexHTML(assetsFS.Open, options)
 	if err != nil {
 		return nil, err
 	}
@@ -97,11 +99,12 @@ func NewStaticAssetsHandler(staticAssetsRoot string, options StaticAssetsHandler
 	return h, nil
 }
 
-func loadIndexBytes(open func(string) (http.File, error), options StaticAssetsHandlerOptions) ([]byte, error) {
+func loadAndEnrichIndexHTML(open func(string) (http.File, error), options StaticAssetsHandlerOptions) ([]byte, error) {
 	indexBytes, err := loadIndexHTML(open)
 	if err != nil {
 		return nil, fmt.Errorf("cannot load index.html: %w", err)
 	}
+	// replace UI config
 	configString := "JAEGER_CONFIG = DEFAULT_CONFIG"
 	if config, err := loadUIConfig(options.UIConfigPath); err != nil {
 		return nil, err
@@ -113,14 +116,19 @@ func loadIndexBytes(open func(string) (http.File, error), options StaticAssetsHa
 		configString = fmt.Sprintf("JAEGER_CONFIG = %v", string(bytes))
 	}
 	indexBytes = configPattern.ReplaceAll(indexBytes, []byte(configString+";"))
+	// replace Jaeger version
+	versionJSON, _ := json.Marshal(version.Get())
+	versionString := fmt.Sprintf("JAEGER_VERSION = %s;", string(versionJSON))
+	indexBytes = versionPattern.ReplaceAll(indexBytes, []byte(versionString))
+	// replace base path
 	if options.BasePath == "" {
 		options.BasePath = "/"
 	}
 	if options.BasePath != "/" {
 		if !strings.HasPrefix(options.BasePath, "/") || strings.HasSuffix(options.BasePath, "/") {
-			return nil, fmt.Errorf(errBadBasePath, options.BasePath)
+			return nil, fmt.Errorf("invalid base path '%s'. Must start but not end with a slash '/', e.g. '/jaeger/ui'", options.BasePath)
 		}
-		indexBytes = basePathPattern.ReplaceAll(indexBytes, []byte(fmt.Sprintf(basePathReplace, options.BasePath)))
+		indexBytes = basePathPattern.ReplaceAll(indexBytes, []byte(fmt.Sprintf(`<base href="%s/"`, options.BasePath)))
 	}
 
 	return indexBytes, nil
@@ -144,7 +152,7 @@ func (sH *StaticAssetsHandler) configListener(watcher *fsnotify.Watcher) {
 			}
 			// this will catch events for all files inside the same directory, which is OK if we don't have many changes
 			sH.options.Logger.Info("reloading UI config", zap.String("filename", sH.options.UIConfigPath))
-			content, err := loadIndexBytes(sH.assetsFS.Open, sH.options)
+			content, err := loadAndEnrichIndexHTML(sH.assetsFS.Open, sH.options)
 			if err != nil {
 				sH.options.Logger.Error("error while reloading the UI config", zap.Error(err))
 			}

cmd/query/app/static_handler_test.go

@@ -95,6 +95,7 @@ func TestRegisterStaticHandler(t *testing.T) {
 
 			html := httpGet("") // get home page
 			assert.Contains(t, html, `JAEGER_CONFIG = {"x":"y"};`, "actual: %v", html)
+			assert.Contains(t, html, `JAEGER_VERSION = {"gitCommit":"","gitVersion":"","buildDate":""};`, "actual: %v", html)
 			assert.Contains(t, html, testCase.expectedBaseHTML, "actual: %v", html)
 
 			asset := httpGet("static/asset.txt")
@@ -110,7 +111,7 @@ func TestNewStaticAssetsHandlerErrors(t *testing.T) {
 	for _, base := range []string{"x", "x/", "/x/"} {
 		_, err := NewStaticAssetsHandler("fixture", StaticAssetsHandlerOptions{UIConfigPath: "fixture/ui-config.json", BasePath: base})
 		require.Errorf(t, err, "basePath=%s", base)
-		assert.Contains(t, err.Error(), "Invalid base path")
+		assert.Contains(t, err.Error(), "invalid base path")
 	}
 }
 

cmd/query/app/ui/placeholder/public/index.html

@@ -4,6 +4,7 @@
     <base href="/" data-inject-target="BASE_URL"/>
     <title>Test Page</title>
     <!-- JAEGER_CONFIG=DEFAULT_CONFIG; -->
+    <!-- JAEGER_VERSION="unknown"; -->
     <body>
         This is a placeholder for Jaeger UI home page.
         If you are seeing this, you are running a binary

pkg/version/build.go

@@ -28,8 +28,8 @@ var (
 // Info holds build information
 type Info struct {
 	GitCommit  string `json:"gitCommit"`
-	GitVersion string `json:"GitVersion"`
-	BuildDate  string `json:"BuildDate"`
+	GitVersion string `json:"gitVersion"`
+	BuildDate  string `json:"buildDate"`
 }
 
 // Get creates and initialized Info object