Merge pull request #80 from shunfei/feature/pid

Write pid to file, resolve #79

conf/conf.go

@@ -55,6 +55,7 @@ type Conf struct {
 	Group   string // 节点分组
 	Noticer string // 通知
 
+	PIDFile  string
 	UUIDFile string
 
 	Ttl        int64 // 节点超时时间，单位秒

conf/files/base.json.sample

@@ -21,5 +21,8 @@
     "Mgo": "@extend:db.json",
     "Mail": "@extend:mail.json",
     "Security": "@extend:security.json",
+    "#comment": "PIDFile and UUIDFile just work for cronnode"
+    "#PIDFile": "Given a none-empty string to write a pid file to the specialed path, or leave it empty to do nothing"
+    "PIDFile": "/tmp/cronsun/cronnode_pid",
     "UUIDFile": "/etc/cronsun/CRONSUN_UUID"
 }

node.go

@@ -25,7 +25,8 @@ const (
 type Node struct {
 	ID       string `bson:"_id" json:"id"`  // machine id
 	PID      string `bson:"pid" json:"pid"` // 进程 pid
-	IP       string `bson:"ip" json:"ip"`   // node ip
+	PIDFile  string `bson:"-" json:"-"`
+	IP       string `bson:"ip" json:"ip"` // node ip
 	Hostname string `bson:"hostname" json:"hostname"`
 
 	Version  string    `bson:"version" json:"version"`

node/node.go

@@ -2,8 +2,11 @@ package node
 
 import (
 	"fmt"
+	"io/ioutil"
 	"os"
+	"path"
 	"strconv"
+	"strings"
 	"time"
 
 	client "github.com/coreos/etcd/clientv3"
@@ -56,6 +59,7 @@ func NewNode(cfg *conf.Conf) (n *Node, err error) {
 		Node: &cronsun.Node{
 			ID:       uuid,
 			PID:      strconv.Itoa(os.Getpid()),
+			PIDFile:  strings.TrimSpace(cfg.PIDFile),
 			IP:       ip.String(),
 			Hostname: hostname,
 		},
@@ -101,9 +105,46 @@ func (n *Node) set() error {
 	}
 
 	n.lID = resp.ID
+	n.writePIDFile()
+
 	return nil
 }
 
+func (n *Node) writePIDFile() {
+	if len(n.PIDFile) == 0 {
+		return
+	}
+
+	filename := "cronnode_pid"
+	if !strings.HasSuffix(n.PIDFile, "/") {
+		filename = path.Base(n.PIDFile)
+	}
+
+	dir := path.Dir(n.PIDFile)
+	err := os.MkdirAll(dir, 0755)
+	if err != nil {
+		log.Errorf("Failed to write pid file: %s", err)
+		return
+	}
+
+	n.PIDFile = path.Join(dir, filename)
+	err = ioutil.WriteFile(n.PIDFile, []byte(n.PID), 0644)
+	if err != nil {
+		log.Errorf("Failed to write pid file: %s", err)
+		return
+	}
+}
+
+func (n *Node) removePIDFile() {
+	if len(n.PIDFile) == 0 {
+		return
+	}
+
+	if err := os.Remove(n.PIDFile); err != nil {
+		log.Warnf("Failed to remove pid file: %s", err)
+	}
+}
+
 // 断网掉线重新注册
 func (n *Node) keepAlive() {
 	duration := time.Duration(n.ttl) * time.Second
@@ -494,4 +535,5 @@ func (n *Node) Stop(i interface{}) {
 	n.Node.Del()
 	n.Client.Close()
 	n.Cron.Stop()
+	n.removePIDFile()
 }