examples: server-sent events: add a second 3rd-party pkg usage example

_examples/README.md

@@ -184,8 +184,9 @@
     * [HTTP/2 Server Push](response-writer/http2push/main.go)
     * [Stream Writer](response-writer/stream-writer/main.go)
     * [Transactions](response-writer/transactions/main.go)
-    * [SSE](response-writer/sse/main.go)
-    * [SSE (third-party package usage for server sent events)](response-writer/sse-third-party/main.go)
+    * [Server-Sent Events](response-writer/sse/main.go)
+        * [SSE 3rd-party (r3labs/sse)](response-writer/sse-third-party/main.go)
+        * [SSE 3rd-party (alexandrevicenzi/go-sse)](response-writer/sse-third-party-2/main.go)
     * Cache
         * [Simple](response-writer/cache/simple/main.go)
         * [Client-Side (304)](response-writer/cache/client-side/main.go)

_examples/response-writer/sse-third-party-2/main.go

@@ -0,0 +1,59 @@
+package main
+
+import (
+	"log"
+	"net/http"
+	"os"
+	"strconv"
+	"time"
+
+	"github.com/alexandrevicenzi/go-sse"
+	"github.com/kataras/iris/v12"
+)
+
+// Install the sse third-party package
+// $ go get -u github.com/alexandrevicenzi/go-sse
+func main() {
+	s := sse.NewServer(&sse.Options{
+		// Increase default retry interval to 10s.
+		RetryInterval: 10 * 1000,
+		// CORS headers
+		Headers: map[string]string{
+			"Access-Control-Allow-Origin":  "*",
+			"Access-Control-Allow-Methods": "GET, OPTIONS",
+			"Access-Control-Allow-Headers": "Keep-Alive,X-Requested-With,Cache-Control,Content-Type,Last-Event-ID",
+		},
+		// Custom channel name generator
+		ChannelNameFunc: func(request *http.Request) string {
+			return request.URL.Path
+		},
+		// Print debug info
+		Logger: log.New(os.Stdout, "go-sse: ", log.Ldate|log.Ltime|log.Lshortfile),
+	})
+
+	defer s.Shutdown()
+
+	app := iris.New()
+	app.Get("/", func(ctx iris.Context) {
+		ctx.ServeFile("../static/index.html")
+	})
+	app.Get("/events/{channel}", iris.FromStd(s))
+
+	go func() {
+		for {
+			s.SendMessage("/events/channel-1", sse.SimpleMessage(time.Now().Format("2006/02/01/ 15:04:05")))
+			time.Sleep(5 * time.Second)
+		}
+	}()
+
+	go func() {
+		i := 0
+		for {
+			i++
+			s.SendMessage("/events/channel-2", sse.SimpleMessage(strconv.Itoa(i)))
+			time.Sleep(5 * time.Second)
+		}
+	}()
+
+	app.Listen(":3000")
+}