Add logger

README.md

@@ -30,3 +30,7 @@ You can try any other router.
 For example, one of the most popular solutions is [julienschmidt/httprouter](https://github.com/julienschmidt/httprouter).
 
 Don't forget to check if tests are still green (`go test -v`) and change them if it is necessary.
+
+## Step 05. Add logger
+
+Add logger ([Sirupsen/logrus](https://github.com/Sirupsen/logrus) is my favourite!) to log requests.

handlers.go

@@ -10,3 +10,12 @@ import (
 func home(c *router.Control) {
 	fmt.Fprintf(c.Writer, "Processing URL %s...", c.Request.URL.Path)
 }
+
+// logger provides a log of requests
+func logger(c *router.Control) {
+	remoteAddr := c.Request.Header.Get("X-Forwarded-For")
+	if remoteAddr == "" {
+		remoteAddr = c.Request.RemoteAddr
+	}
+	log.Infof("%s %s %s", remoteAddr, c.Request.Method, c.Request.URL.Path)
+}

handlers_test.go

@@ -1,15 +1,26 @@
 package main
 
 import (
+	"bytes"
+	"encoding/json"
 	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"strings"
 	"testing"
 
+	"github.com/Sirupsen/logrus"
 	"github.com/takama/router"
 )
 
+// buffer is a special variable to save log messages
+var buffer bytes.Buffer
+
+func init() {
+	log.Out = &buffer
+	log.Formatter = &logrus.JSONFormatter{}
+}
+
 // TestHandler is the simplest test: check base (/) URL
 func TestHandler(t *testing.T) {
 	r := router.New()
@@ -39,3 +50,32 @@ func TestHandler(t *testing.T) {
 		)
 	}
 }
+
+// TestLogger checks if logger handler works correctly
+func TestLogger(t *testing.T) {
+	r := router.New()
+	r.Logger = logger
+
+	ts := httptest.NewServer(r)
+	defer ts.Close()
+
+	_, err := http.Get(ts.URL + "/")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	formated := struct {
+		Level string `json:"level"`
+		Msg   string `json:"msg"`
+		Time  string `json:"time"`
+	}{}
+	err = json.NewDecoder(&buffer).Decode(&formated)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	msgParts := strings.Split(formated.Msg, " ")
+	if len(msgParts) != 3 {
+		t.Fatalf("Wrong message was logged: %s", formated.Msg)
+	}
+}

main.go

@@ -1,13 +1,17 @@
 package main
 
 import (
+	"github.com/Sirupsen/logrus"
 	"github.com/takama/router"
 )
 
+var log = logrus.New()
+
 // Run server: go build && step-by-step
 // Try requests: curl http://127.0.0.1:8000/test
 func main() {
 	r := router.New()
+	r.Logger = logger
 	r.GET("/", home)
 	r.Listen(":8000")
 }