add some parameters to config for supporting #1936 (#1956)

* add some parameters to config for supporting #1936

* remove go:embed

* apply code review  - 1956#issuecomment-1169811117

* lint

Co-authored-by: Muhammed Efe Çetin <efectn@protonmail.com>

middleware/monitor/README.md

@@ -53,7 +53,7 @@ type Config struct {
 	// Optional. Default: 3 seconds
 	Refresh time.Duration
 
-	// To disable serving HTML, you can make true this option.
+	// Whether the service should expose only the monitoring API.
 	//
 	// Optional. Default: false
 	APIOnly bool
@@ -62,6 +62,23 @@ type Config struct {
 	//
 	// Optional. Default: nil
 	Next func(c *fiber.Ctx) bool
+
+	// Custom HTML Code to Head Section(Before End)
+	//
+	// Optional. Default: empty
+	CustomHead string
+
+	// FontURL for specify font resource path or URL . also you can use relative path
+	//
+	// Optional. Default: https://fonts.googleapis.com/css2?family=Roboto:wght@400;900&display=swap
+
+	FontURL string
+	// ChartJsURL for specify ChartJS library  path or URL . also you can use relative path
+	//
+	// Optional. Default: https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js
+
+	ChartJsURL string
+
 }
 ```
 
@@ -73,5 +90,9 @@ var ConfigDefault = Config{
 	Refresh: 3 * time.Second,
 	APIOnly: false,
 	Next:    nil,
+	CustomHead:"",
+	FontURL:"https://fonts.googleapis.com/css2?family=Roboto:wght@400;900&display=swap",
+	ChartJsURL:"https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js"
+
 }
 ```

middleware/monitor/config.go

@@ -28,28 +28,49 @@ type Config struct {
 	// Optional. Default: nil
 	Next func(c *fiber.Ctx) bool
 
-	// customized indexHtml
+	// Custom HTML Code to Head Section(Before End)
+	//
+	// Optional. Default: empty
+	CustomHead string
+
+	// FontURL for specify font resource path or URL . also you can use relative path
+	//
+	// Optional. Default: https://fonts.googleapis.com/css2?family=Roboto:wght@400;900&display=swap
+	FontURL string
+
+	// ChartJsURL for specify ChartJS library  path or URL . also you can use relative path
+	//
+	// Optional. Default: https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js
+	ChartJsURL string
+
 	index string
 }
 
 var ConfigDefault = Config{
-	Title:   defaultTitle,
+	Title:      defaultTitle,
-	Refresh: defaultRefresh,
+	Refresh:    defaultRefresh,
-	APIOnly: false,
+	FontURL:    defaultFontURL,
-	Next:    nil,
+	ChartJsURL: defaultChartJsURL,
-	index:   newIndex(defaultTitle, defaultRefresh),
+	CustomHead: defaultCustomHead,
+	APIOnly:    false,
+	Next:       nil,
+	index: newIndex(viewBag{defaultTitle, defaultRefresh, defaultFontURL, defaultChartJsURL,
+		defaultCustomHead}),
 }
 
 func configDefault(config ...Config) Config {
 	// Users can change ConfigDefault.Title/Refresh which then
 	// become incompatible with ConfigDefault.index
-	if ConfigDefault.Title != defaultTitle || ConfigDefault.Refresh != defaultRefresh {
+	if ConfigDefault.Title != defaultTitle || ConfigDefault.Refresh != defaultRefresh ||
+		ConfigDefault.FontURL != defaultFontURL || ConfigDefault.ChartJsURL != defaultChartJsURL ||
+		ConfigDefault.CustomHead != defaultCustomHead {
 
 		if ConfigDefault.Refresh < minRefresh {
 			ConfigDefault.Refresh = minRefresh
 		}
 		// update default index with new default title/refresh
-		ConfigDefault.index = newIndex(ConfigDefault.Title, ConfigDefault.Refresh)
+		ConfigDefault.index = newIndex(viewBag{ConfigDefault.Title,
+			ConfigDefault.Refresh, ConfigDefault.FontURL, ConfigDefault.ChartJsURL, ConfigDefault.CustomHead})
 	}
 
 	// Return default config if nothing provided
@@ -68,7 +89,13 @@ func configDefault(config ...Config) Config {
 	if cfg.Refresh == 0 {
 		cfg.Refresh = ConfigDefault.Refresh
 	}
+	if cfg.FontURL == "" {
+		cfg.FontURL = defaultFontURL
+	}
 
+	if cfg.ChartJsURL == "" {
+		cfg.ChartJsURL = defaultChartJsURL
+	}
 	if cfg.Title == ConfigDefault.Title && cfg.Refresh == ConfigDefault.Refresh {
 		cfg.index = ConfigDefault.index
 	} else {
@@ -76,7 +103,8 @@ func configDefault(config ...Config) Config {
 			cfg.Refresh = minRefresh
 		}
 		// update cfg.index with custom title/refresh
-		cfg.index = newIndex(cfg.Title, cfg.Refresh)
+		cfg.index = newIndex(viewBag{cfg.Title,
+			cfg.Refresh, cfg.FontURL, cfg.ChartJsURL, cfg.CustomHead})
 	}
 
 	if cfg.Next == nil {

middleware/monitor/index.go

@@ -6,25 +6,37 @@ import (
 	"time"
 )
 
-// returns index with new title/refresh
+type viewBag struct {
-func newIndex(title string, refresh time.Duration) string {
+	title      string
+	refresh    time.Duration
+	fontUrl    string
+	chartJsUrl string
+	customHead string
+}
 
-	timeout := refresh.Milliseconds() - timeoutDiff
+// returns index with new title/refresh
+func newIndex(dat viewBag) string {
+
+	timeout := dat.refresh.Milliseconds() - timeoutDiff
 	if timeout < timeoutDiff {
 		timeout = timeoutDiff
 	}
 	ts := strconv.FormatInt(timeout, 10)
-
+	replacer := strings.NewReplacer("$TITLE", dat.title, "$TIMEOUT", ts,
-	index := strings.ReplaceAll(indexHtml, "$TITLE", title)
+		"$FONT_URL", dat.fontUrl, "$CHART_JS_URL", dat.chartJsUrl, "$CUSTOM_HEAD", dat.customHead,
-	return strings.ReplaceAll(index, "$TIMEOUT", ts)
+	)
+	return replacer.Replace(indexHtml)
 }
 
 const (
 	defaultTitle = "Fiber Monitor"
 
-	defaultRefresh = 3 * time.Second
+	defaultRefresh    = 3 * time.Second
-	timeoutDiff    = 200 // timeout will be Refresh (in millisconds) - timeoutDiff
+	timeoutDiff       = 200 // timeout will be Refresh (in milliseconds) - timeoutDiff
-	minRefresh     = timeoutDiff * time.Millisecond
+	minRefresh        = timeoutDiff * time.Millisecond
+	defaultFontURL    = `https://fonts.googleapis.com/css2?family=Roboto:wght@400;900&display=swap`
+	defaultChartJsURL = `https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js`
+	defaultCustomHead = ``
 
 	// parametrized by $TITLE and $TIMEOUT
 	indexHtml = `<!DOCTYPE html>
@@ -32,8 +44,9 @@ const (
 <head>
 	<meta charset="UTF-8">
 	<meta name="viewport" content="width=device-width, initial-scale=1.0">
-	<link href="https://fonts.googleapis.com/css2?family=Roboto:wght@400;900&display=swap" rel="stylesheet">
+	<link href="$FONT_URL" rel="stylesheet">
-	<script src="https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js"></script>
+	<script src="$CHART_JS_URL"></script>
+
 	<title>$TITLE</title>
 <style>
 	body {
@@ -80,6 +93,7 @@ const (
 		width: 200px;
 		height: 180px;
 	}
+$CUSTOM_HEAD
 </style>
 </head>
 <body>
@@ -253,5 +267,6 @@ const (
 	fetchJSON()
 </script>
 </body>
-</html>`
+</html>
+`
 )

middleware/monitor/monitor_test.go

@@ -61,6 +61,50 @@ func Test_Monitor_Html(t *testing.T) {
 		conf.Refresh.Milliseconds()-timeoutDiff)
 	utils.AssertEqual(t, true, bytes.Contains(buf, []byte(timeoutLine)))
 }
+func Test_Monitor_Html_CustomCodes(t *testing.T) {
+	t.Parallel()
+
+	app := fiber.New()
+
+	// defaults
+	app.Get("/", New())
+	resp, err := app.Test(httptest.NewRequest(fiber.MethodGet, "/", nil))
+
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, 200, resp.StatusCode)
+	utils.AssertEqual(t, fiber.MIMETextHTMLCharsetUTF8,
+		resp.Header.Get(fiber.HeaderContentType))
+	buf, err := ioutil.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, true, bytes.Contains(buf, []byte("<title>"+defaultTitle+"</title>")))
+	timeoutLine := fmt.Sprintf("setTimeout(fetchJSON, %d)",
+		defaultRefresh.Milliseconds()-timeoutDiff)
+	utils.AssertEqual(t, true, bytes.Contains(buf, []byte(timeoutLine)))
+
+	// custom config
+	conf := Config{Title: "New " + defaultTitle, Refresh: defaultRefresh + time.Second,
+		ChartJsURL: "https://cdnjs.com/libraries/Chart.js",
+		FontURL:    "/public/my-font.css",
+		CustomHead: `<style>body{background:#fff}</style>`,
+	}
+	app.Get("/custom", New(conf))
+	resp, err = app.Test(httptest.NewRequest(fiber.MethodGet, "/custom", nil))
+
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, 200, resp.StatusCode)
+	utils.AssertEqual(t, fiber.MIMETextHTMLCharsetUTF8,
+		resp.Header.Get(fiber.HeaderContentType))
+	buf, err = ioutil.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, true, bytes.Contains(buf, []byte("<title>"+conf.Title+"</title>")))
+	utils.AssertEqual(t, true, bytes.Contains(buf, []byte("https://cdnjs.com/libraries/Chart.js")))
+	utils.AssertEqual(t, true, bytes.Contains(buf, []byte("/public/my-font.css")))
+	utils.AssertEqual(t, true, bytes.Contains(buf, []byte(conf.CustomHead)))
+
+	timeoutLine = fmt.Sprintf("setTimeout(fetchJSON, %d)",
+		conf.Refresh.Milliseconds()-timeoutDiff)
+	utils.AssertEqual(t, true, bytes.Contains(buf, []byte(timeoutLine)))
+}
 
 // go test -run Test_Monitor_JSON -race
 func Test_Monitor_JSON(t *testing.T) {