feat: add multiple service example. (#1119)

README.md

@@ -1154,6 +1154,88 @@ func main() {
 }
 ```
 
+### Run multiple service using Gin
+
+See the [question](https://github.com/gin-gonic/gin/issues/346) and try the folling example:
+
+[embedmd]:# (examples/multiple-service/main.go go)
+```go
+package main
+
+import (
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"golang.org/x/sync/errgroup"
+)
+
+var (
+	g errgroup.Group
+)
+
+func router01() http.Handler {
+	e := gin.New()
+	e.Use(gin.Recovery())
+	e.GET("/", func(c *gin.Context) {
+		c.JSON(
+			http.StatusOK,
+			gin.H{
+				"code":  http.StatusOK,
+				"error": "Welcome server 01",
+			},
+		)
+	})
+
+	return e
+}
+
+func router02() http.Handler {
+	e := gin.New()
+	e.Use(gin.Recovery())
+	e.GET("/", func(c *gin.Context) {
+		c.JSON(
+			http.StatusOK,
+			gin.H{
+				"code":  http.StatusOK,
+				"error": "Welcome server 02",
+			},
+		)
+	})
+
+	return e
+}
+
+func main() {
+	server01 := &http.Server{
+		Addr:         ":8080",
+		Handler:      router01(),
+		ReadTimeout:  5 * time.Second,
+		WriteTimeout: 10 * time.Second,
+	}
+
+	server02 := &http.Server{
+		Addr:         ":8081",
+		Handler:      router02(),
+		ReadTimeout:  5 * time.Second,
+		WriteTimeout: 10 * time.Second,
+	}
+
+	g.Go(func() error {
+		return server01.ListenAndServe()
+	})
+
+	g.Go(func() error {
+		return server02.ListenAndServe()
+	})
+
+	if err := g.Wait(); err != nil {
+		log.Fatal(err)
+	}
+}
+```
+
 ### Graceful restart or stop
 
 Do you want to graceful restart or stop your web server?

examples/multiple-service/main.go

@@ -0,0 +1,74 @@
+package main
+
+import (
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"golang.org/x/sync/errgroup"
+)
+
+var (
+	g errgroup.Group
+)
+
+func router01() http.Handler {
+	e := gin.New()
+	e.Use(gin.Recovery())
+	e.GET("/", func(c *gin.Context) {
+		c.JSON(
+			http.StatusOK,
+			gin.H{
+				"code":  http.StatusOK,
+				"error": "Welcome server 01",
+			},
+		)
+	})
+
+	return e
+}
+
+func router02() http.Handler {
+	e := gin.New()
+	e.Use(gin.Recovery())
+	e.GET("/", func(c *gin.Context) {
+		c.JSON(
+			http.StatusOK,
+			gin.H{
+				"code":  http.StatusOK,
+				"error": "Welcome server 02",
+			},
+		)
+	})
+
+	return e
+}
+
+func main() {
+	server01 := &http.Server{
+		Addr:         ":8080",
+		Handler:      router01(),
+		ReadTimeout:  5 * time.Second,
+		WriteTimeout: 10 * time.Second,
+	}
+
+	server02 := &http.Server{
+		Addr:         ":8081",
+		Handler:      router02(),
+		ReadTimeout:  5 * time.Second,
+		WriteTimeout: 10 * time.Second,
+	}
+
+	g.Go(func() error {
+		return server01.ListenAndServe()
+	})
+
+	g.Go(func() error {
+		return server02.ListenAndServe()
+	})
+
+	if err := g.Wait(); err != nil {
+		log.Fatal(err)
+	}
+}