✏️ feature: useCDN option for monitor middleware

middleware/monitor/README.md

@@ -1,8 +1,6 @@
 # Monitor
 Monitor middleware for [Fiber](https://github.com/gofiber/fiber) that reports server metrics, inspired by [express-status-monitor](https://github.com/RafalWilinski/express-status-monitor)
 
-:warning: **Warning:** Monitor is still in beta, API might change in the future!
-
 ![](https://i.imgur.com/nHAtBpJ.gif)
 
 ### Signatures
@@ -58,6 +56,12 @@ type Config struct {
 	// Optional. Default: false
 	APIOnly bool
 
+	// UseCDN is an option to get Chart.js from jsdelivr cdn.
+	// If you dont want to use cdn, Chart.js will be served from another route.
+	//
+	// Optional. Default: false
+	UseCDN bool
+
 	// Next defines a function to skip this middleware when returned true.
 	//
 	// Optional. Default: nil

middleware/monitor/config.go

@@ -23,6 +23,12 @@ type Config struct {
 	// Optional. Default: false
 	APIOnly bool
 
+	// UseCDN is an option to get Chart.js from jsdelivr cdn.
+	// If you dont want to use cdn, Chart.js will be served from another route.
+	//
+	// Optional. Default: false
+	UseCDN bool
+
 	// Next defines a function to skip this middleware when returned true.
 	//
 	// Optional. Default: nil

middleware/monitor/monitor.go

@@ -2,6 +2,7 @@ package monitor
 
 import (
 	"os"
+	"strings"
 	"sync"
 	"sync/atomic"
 	"time"
@@ -81,6 +82,12 @@ func New(config ...Config) fiber.Handler {
 		if c.Method() != fiber.MethodGet {
 			return fiber.ErrMethodNotAllowed
 		}
+
+		if c.Get("Sec-Fetch-Dest") == "script" {
+			c.Set(fiber.HeaderContentType, fiber.MIMEApplicationJavaScriptCharsetUTF8)
+			return c.Status(fiber.StatusOK).SendString(chartJS)
+		}
+
 		if c.Get(fiber.HeaderAccept) == fiber.MIMEApplicationJSON || cfg.APIOnly {
 			mutex.Lock()
 			data.PID.CPU = monitPidCpu.Load().(float64)
@@ -95,8 +102,16 @@ func New(config ...Config) fiber.Handler {
 			mutex.Unlock()
 			return c.Status(fiber.StatusOK).JSON(data)
 		}
+
 		c.Set(fiber.HeaderContentType, fiber.MIMETextHTMLCharsetUTF8)
-		return c.Status(fiber.StatusOK).SendString(cfg.index)
+
+		// Return index by check UseCDN config field.
+		if cfg.UseCDN {
+			return c.Status(fiber.StatusOK).SendString(cfg.index)
+		}
+
+		index := strings.ReplaceAll(cfg.index, "https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js", c.OriginalURL())
+		return c.Status(fiber.StatusOK).SendString(index)
 	}
 }
 

middleware/monitor/monitor_test.go

@@ -130,7 +130,7 @@ func Test_Monitor_Next(t *testing.T) {
 
 // go test -run Test_Monitor_APIOnly -race
 func Test_Monitor_APIOnly(t *testing.T) {
-	//t.Parallel()
+	t.Parallel()
 
 	app := fiber.New()
 
@@ -150,3 +150,45 @@ func Test_Monitor_APIOnly(t *testing.T) {
 	utils.AssertEqual(t, true, bytes.Contains(b, []byte("pid")))
 	utils.AssertEqual(t, true, bytes.Contains(b, []byte("os")))
 }
+
+// go test -run Test_Monitor_UseCDN -race
+func Test_Monitor_UseCDN(t *testing.T) {
+	t.Parallel()
+
+	app := fiber.New()
+
+	app.Get("/", New(Config{
+		UseCDN: true,
+	}))
+
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
+	resp, err := app.Test(req)
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, 200, resp.StatusCode)
+	utils.AssertEqual(t, fiber.MIMETextHTMLCharsetUTF8, resp.Header.Get(fiber.HeaderContentType))
+
+	b, err := ioutil.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, true, bytes.Contains(b, []byte(`<script src="https://cdn.jsdelivr.net/npm/chart.js@2.9/dist/Chart.bundle.min.js"></script>`)))
+}
+
+// go test -run Test_Monitor_Script -race
+func Test_Monitor_Script(t *testing.T) {
+	t.Parallel()
+
+	app := fiber.New()
+
+	app.Get("/", New())
+
+	req := httptest.NewRequest(fiber.MethodGet, "/", nil)
+	req.Header.Set("Sec-Fetch-Dest", "script")
+	resp, err := app.Test(req)
+	fmt.Print(resp.Header.Get("Sec-Fetch-Dest"))
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, 200, resp.StatusCode)
+	utils.AssertEqual(t, "script", resp.Request.Header.Get("Sec-Fetch-Dest"))
+
+	b, err := ioutil.ReadAll(resp.Body)
+	utils.AssertEqual(t, nil, err)
+	utils.AssertEqual(t, true, bytes.Contains(b, []byte(`Chart.js v2.9.0`)))
+}