Added simple testing documentation and examples (#1156)

README.md

@@ -1344,6 +1344,52 @@ func main() {
 }
 ```
 
+## Testing
+
+The `net/http/httptest` package is preferable way for HTTP testing.
+
+```go
+package main
+
+func setupRouter() *gin.Engine {
+	r := gin.Default()
+	r.GET("/ping", func(c *gin.Context) {
+		c.String(200, "pong")
+	})
+	return r
+}
+
+func main() {
+	r := setupRouter()
+	r.Run(":8080")
+}
+```
+
+Test for code example above:
+
+```go
+package main
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPingRoute(t *testing.T) {
+	router := setupRouter()
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/ping", nil)
+	router.ServeHTTP(w, req)
+
+	assert.Equal(t, 200, w.Code)
+	assert.Equal(t, "pong", w.Body.String())
+}
+```
+
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examples/basic/main.go

@@ -6,7 +6,7 @@ import (
 
 var DB = make(map[string]string)
 
-func main() {
+func setupRouter() *gin.Engine {
 	// Disable Console Color
 	// gin.DisableConsoleColor()
 	r := gin.Default()
@@ -53,6 +53,11 @@ func main() {
 		}
 	})
 
+	return r
+}
+
+func main() {
+	r := setupRouter()
 	// Listen and Server in 0.0.0.0:8080
 	r.Run(":8080")
 }

examples/basic/main_test.go

@@ -0,0 +1,20 @@
+package main
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestPingRoute(t *testing.T) {
+	router := setupRouter()
+
+	w := httptest.NewRecorder()
+	req, _ := http.NewRequest("GET", "/ping", nil)
+	router.ServeHTTP(w, req)
+
+	assert.Equal(t, 200, w.Code)
+	assert.Equal(t, "pong", w.Body.String())
+}