Merge pull request #27 from jiajunhuang/improve_coverage_for_config

improve coverage for config

balancer.go

@@ -11,7 +11,7 @@ const (
 	LBMRandom = "random"
 )
 
-// Backend is the backend server, usally a app server like: gunicorn+flask
+// Backend is the backend server, usually a app server like: gunicorn+flask
 type Backend struct {
 	Weight int
 	URL    string // cache the result

config.go

@@ -146,15 +146,13 @@ func configKeeper() {
 	b := breakerConfig{make(map[string](appConfig))}
 
 	fileBytes := readFromFile(*configPath)
-	if err := json.Unmarshal(fileBytes, &b); err != nil && len(fileBytes) > 0 {
-		log.Printf("failed to unmarshal config file %s because %s", *configPath, err)
-	}
-
-	if len(b.APPs) > 0 {
+	if err := json.Unmarshal(fileBytes, &b); err == nil && len(b.APPs) > 0 {
 		log.Printf("loading config from config file")
 		for k, v := range b.APPs {
 			breaker.apps[k] = getAPP(&v)
 		}
+	} else {
+		log.Printf("failed to unmarshal config file %s because %s", *configPath, err)
 	}
 
 	// listen channel for sync

config_test.go

@@ -2,8 +2,10 @@ package main
 
 import (
 	"bytes"
+	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"os"
 	"testing"
 )
 
@@ -81,3 +83,88 @@ func TestGetBalancer(t *testing.T) {
 	defer shouldPanic()
 	getBalancer("what")
 }
+
+func TestReadFromFile(t *testing.T) {
+	os.Remove(*configPath)
+	defer os.Remove(*configPath)
+
+	f, err := os.OpenFile(*configPath, os.O_CREATE|os.O_RDWR, 0644)
+	if err != nil {
+		t.Errorf("failed to open config file: %s", err)
+	}
+	defer f.Close()
+	content := []byte("hello world")
+	f.Write(content)
+
+	readContent := readFromFile(*configPath)
+	if !bytes.Equal(readContent, content) {
+		t.Errorf("read from file return bad content: %s", string(readContent))
+	}
+}
+
+func TestConfigKeeper(t *testing.T) {
+	os.Remove(*configPath)
+	defer os.Remove(*configPath)
+
+	config := appConfig{
+		"www.example.com",
+		[]string{"192.168.1.1:80"},
+		[]int{1},
+		0.3,
+		false,
+		LBMWRR,
+		[]string{"/"},
+		[]string{"GET"},
+	}
+
+	go configKeeper()
+
+	configSync <- config
+}
+
+func TestConfigKeeperBadJSON(t *testing.T) {
+	os.Remove(*configPath)
+	defer os.Remove(*configPath)
+	f, err := os.OpenFile(*configPath, os.O_CREATE|os.O_RDWR, 0644)
+	if err != nil {
+		t.Errorf("failed to open config file: %s", err)
+	}
+	defer f.Close()
+	content := []byte("hello world")
+	f.Write(content)
+
+	go configKeeper()
+}
+
+func TestConfigKeeperGoodJSON(t *testing.T) {
+	os.Remove(*configPath)
+	//defer os.Remove(*configPath)
+	f, err := os.OpenFile(*configPath, os.O_CREATE|os.O_RDWR, 0644)
+	if err != nil {
+		t.Errorf("failed to open config file: %s", err)
+	}
+	config := appConfig{
+		"www.example.com",
+		[]string{"192.168.1.1:80"},
+		[]int{1},
+		0.3,
+		false,
+		LBMWRR,
+		[]string{"/"},
+		[]string{"GET"},
+	}
+	breakerConfig := make(map[string]appConfig)
+	breakerConfig[config.Name] = config
+	fileBytes, err := json.Marshal(breakerConfig)
+	if err != nil {
+		t.Errorf("failed to marshal breaker config: %s", err)
+	}
+	f.Truncate(0)
+	f.Seek(0, 0)
+	f.Write(fileBytes)
+	f.Close()
+
+	go configKeeper()
+
+	close(configSync)
+}