Make AccessLogApacheMiddleware work with incomplete middleware stack.

This makes AccessLogApacheMiddleware work even if Timer and Recorder are
missing. In that case, there is not much to log, but it should not fail.
Note, AccessLogJsonMiddleware already behaves that way.

Author: ant0ine

Diff for: rest/access_log_apache.go

@@ -51,7 +51,7 @@ const (
 )
 
 // AccessLogApacheMiddleware produces the access log following a format inspired by Apache
-// mod_log_config. It depends on TimerMiddleware and RecorderMiddleware that must be in the wrapped
+// mod_log_config. It depends on TimerMiddleware and RecorderMiddleware that should be in the wrapped
 // middlewares. It also uses request.Env["REMOTE_USER"].(string) set by the auth middlewares.
 type AccessLogApacheMiddleware struct {
 
@@ -105,8 +105,8 @@ var apacheAdapter = strings.NewReplacer(
 	"%r", "{{.R.Method}} {{.R.URL.RequestURI}} {{.R.Proto}}",
 	"%s", "{{.StatusCode}}",
 	"%S", "\033[{{.StatusCode | statusCodeColor}}m{{.StatusCode}}",
-	"%t", "{{.StartTime.Format \"02/Jan/2006:15:04:05 -0700\"}}",
-	"%T", "{{.ResponseTime.Seconds | printf \"%.3f\"}}",
+	"%t", "{{if .StartTime}}{{.StartTime.Format \"02/Jan/2006:15:04:05 -0700\"}}{{end}}",
+	"%T", "{{if .ResponseTime}}{{.ResponseTime.Seconds | printf \"%.3f\"}}{{end}}",
 	"%u", "{{.RemoteUser | dashIfEmptyStr}}",
 	"%{User-Agent}i", "{{.R.UserAgent | dashIfEmptyStr}}",
 	"%{Referer}i", "{{.R.Referer | dashIfEmptyStr}}",
@@ -185,7 +185,10 @@ func (u *accessLogUtil) ApacheQueryString() string {
 
 // When the request entered the timer middleware.
 func (u *accessLogUtil) StartTime() *time.Time {
-	return u.R.Env["START_TIME"].(*time.Time)
+	if u.R.Env["START_TIME"] != nil {
+		return u.R.Env["START_TIME"].(*time.Time)
+	}
+	return nil
 }
 
 // If remoteAddr is set then return is without the port number, apache log style.
@@ -200,12 +203,18 @@ func (u *accessLogUtil) ApacheRemoteAddr() string {
 
 // As recorded by the recorder middleware.
 func (u *accessLogUtil) StatusCode() int {
-	return u.R.Env["STATUS_CODE"].(int)
+	if u.R.Env["STATUS_CODE"] != nil {
+		return u.R.Env["STATUS_CODE"].(int)
+	}
+	return 0
 }
 
 // As mesured by the timer middleware.
 func (u *accessLogUtil) ResponseTime() *time.Duration {
-	return u.R.Env["ELAPSED_TIME"].(*time.Duration)
+	if u.R.Env["ELAPSED_TIME"] != nil {
+		return u.R.Env["ELAPSED_TIME"].(*time.Duration)
+	}
+	return nil
 }
 
 // Process id.
@@ -215,5 +224,8 @@ func (u *accessLogUtil) Pid() int {
 
 // As recorded by the recorder middleware.
 func (u *accessLogUtil) BytesWritten() int64 {
-	return u.R.Env["BYTES_WRITTEN"].(int64)
+	if u.R.Env["BYTES_WRITTEN"] != nil {
+		return u.R.Env["BYTES_WRITTEN"].(int64)
+	}
+	return 0
 }

Diff for: rest/access_log_apache_test.go

@@ -43,3 +43,36 @@ func TestAccessLogApacheMiddleware(t *testing.T) {
 		t.Errorf("Got: %s", buffer.String())
 	}
 }
+
+func TestAccessLogApacheMiddlewareMissingData(t *testing.T) {
+
+	api := NewApi()
+
+	// the uncomplete middlewares stack
+	buffer := bytes.NewBufferString("")
+	api.Use(&AccessLogApacheMiddleware{
+		Logger:       log.New(buffer, "", 0),
+		Format:       CommonLogFormat,
+		textTemplate: nil,
+	})
+
+	// a simple app
+	api.SetApp(AppSimple(func(w ResponseWriter, r *Request) {
+		w.WriteJson(map[string]string{"Id": "123"})
+	}))
+
+	// wrap all
+	handler := api.MakeHandler()
+
+	req := test.MakeSimpleRequest("GET", "http://localhost/", nil)
+	recorded := test.RunRequest(t, handler, req)
+	recorded.CodeIs(200)
+	recorded.ContentTypeIsJson()
+
+	// not much to log when the Env data is missing, but this should still work
+	apacheCommon := regexp.MustCompile(` - -  "GET / HTTP/1.1" 0 -`)
+
+	if !apacheCommon.Match(buffer.Bytes()) {
+		t.Errorf("Got: %s", buffer.String())
+	}
+}