From ce2201c39214775ddfff8f79549473d64160aa39 Mon Sep 17 00:00:00 2001
From: Manu Mtz-Almeida <manu.valladolid@gmail.com>
Date: Sun, 16 Aug 2015 16:19:51 +0200
Subject: [PATCH] router.Run() can be called without parameters. #405

---
 gin.go                  |  7 ++--
 gin_integration_test.go | 71 +++++++++++++++++++++++++++++++----------
 utils.go                | 18 +++++++++++
 3 files changed, 76 insertions(+), 20 deletions(-)

diff --git a/gin.go b/gin.go
index c9d38d68..21fc89fc 100644
--- a/gin.go
+++ b/gin.go
@@ -228,11 +228,12 @@ func iterate(path, method string, routes RoutesInfo, root *node) RoutesInfo {
 // Run attaches the router to a http.Server and starts listening and serving HTTP requests.
 // It is a shortcut for http.ListenAndServe(addr, router)
 // Note: this method will block the calling goroutine undefinitelly unless an error happens.
-func (engine *Engine) Run(addr string) (err error) {
-	debugPrint("Listening and serving HTTP on %s\n", addr)
+func (engine *Engine) Run(addr ...string) (err error) {
 	defer func() { debugPrintError(err) }()
 
-	err = http.ListenAndServe(addr, engine)
+	address := resolveAddress(addr)
+	debugPrint("Listening and serving HTTP on %s\n", address)
+	err = http.ListenAndServe(address, engine)
 	return
 }
 
diff --git a/gin_integration_test.go b/gin_integration_test.go
index f7ae0758..0665a61d 100644
--- a/gin_integration_test.go
+++ b/gin_integration_test.go
@@ -2,49 +2,86 @@ package gin
 
 import (
 	"bufio"
-	"bytes"
 	"fmt"
 	"io/ioutil"
 	"net"
 	"net/http"
+	"os"
 	"testing"
 	"time"
 
 	"github.com/stretchr/testify/assert"
 )
 
-func TestRun(t *testing.T) {
-	buffer := new(bytes.Buffer)
+func testRequest(t *testing.T, url string) {
+	resp, err := http.Get(url)
+	defer resp.Body.Close()
+	assert.NoError(t, err)
+
+	body, ioerr := ioutil.ReadAll(resp.Body)
+	assert.NoError(t, ioerr)
+	assert.Equal(t, "it worked", string(body), "resp body should match")
+	assert.Equal(t, "200 OK", resp.Status, "should get a 200")
+}
+
+func TestRunEmpty(t *testing.T) {
+	SetMode(DebugMode)
+	os.Setenv("PORT", "")
 	router := New()
 	go func() {
-		router.Use(LoggerWithWriter(buffer))
 		router.GET("/example", func(c *Context) { c.String(http.StatusOK, "it worked") })
-		router.Run(":5150")
+		assert.NoError(t, router.Run())
+	}()
+	// have to wait for the goroutine to start and run the server
+	// otherwise the main thread will complete
+	time.Sleep(5 * time.Millisecond)
+
+	assert.Error(t, router.Run(":8080"))
+	testRequest(t, "http://localhost:8080/example")
+}
+
+func TestRunEmptyWithEnv(t *testing.T) {
+	os.Setenv("PORT", "3123")
+	router := New()
+	go func() {
+		router.GET("/example", func(c *Context) { c.String(http.StatusOK, "it worked") })
+		assert.NoError(t, router.Run())
+	}()
+	// have to wait for the goroutine to start and run the server
+	// otherwise the main thread will complete
+	time.Sleep(5 * time.Millisecond)
+
+	assert.Error(t, router.Run(":3123"))
+	testRequest(t, "http://localhost:3123/example")
+}
+
+func TestRunTooMuchParams(t *testing.T) {
+	router := New()
+	assert.Panics(t, func() {
+		router.Run("2", "2")
+	})
+}
+
+func TestRunWithPort(t *testing.T) {
+	router := New()
+	go func() {
+		router.GET("/example", func(c *Context) { c.String(http.StatusOK, "it worked") })
+		assert.NoError(t, router.Run(":5150"))
 	}()
 	// have to wait for the goroutine to start and run the server
 	// otherwise the main thread will complete
 	time.Sleep(5 * time.Millisecond)
 
 	assert.Error(t, router.Run(":5150"))
-
-	resp, err := http.Get("http://localhost:5150/example")
-	defer resp.Body.Close()
-	assert.NoError(t, err)
-
-	body, ioerr := ioutil.ReadAll(resp.Body)
-	assert.NoError(t, ioerr)
-	assert.Equal(t, "it worked", string(body[:]), "resp body should match")
-	assert.Equal(t, "200 OK", resp.Status, "should get a 200")
+	testRequest(t, "http://localhost:5150/example")
 }
 
 func TestUnixSocket(t *testing.T) {
-	buffer := new(bytes.Buffer)
 	router := New()
 
 	go func() {
-		router.Use(LoggerWithWriter(buffer))
 		router.GET("/example", func(c *Context) { c.String(http.StatusOK, "it worked") })
-		router.RunUnix("/tmp/unix_unit_test")
+		assert.NoError(t, router.RunUnix("/tmp/unix_unit_test"))
 	}()
 	// have to wait for the goroutine to start and run the server
 	// otherwise the main thread will complete
diff --git a/utils.go b/utils.go
index 7e646876..533888d1 100644
--- a/utils.go
+++ b/utils.go
@@ -7,6 +7,7 @@ package gin
 import (
 	"encoding/xml"
 	"net/http"
+	"os"
 	"path"
 	"reflect"
 	"runtime"
@@ -129,3 +130,20 @@ func joinPaths(absolutePath, relativePath string) string {
 	}
 	return finalPath
 }
+
+func resolveAddress(addr []string) string {
+	switch len(addr) {
+	case 0:
+		if port := os.Getenv("PORT"); len(port) > 0 {
+			debugPrint("Environment variable PORT=\"%s\"", port)
+			return ":" + port
+		} else {
+			debugPrint("Environment variable PORT is undefined. Using port :8080 by default")
+			return ":8080"
+		}
+	case 1:
+		return addr[0]
+	default:
+		panic("too much parameters")
+	}
+}