Merge pull request #3524 from bacongobbler/logger-enhancements

feat(logger): expose config as flags

Author: Matthew Fisher

logger/README.md

@@ -10,19 +10,9 @@ the [Deis Project](https://github.com/deis/deis).
 
 ## Usage
 
-Please consult the [Makefile](Makefile) for current instructions on how to build, test, push,
-install, and start **deis/logger**.
-
-## Environment Variables
-
-* **DEBUG** enables verbose output if set
-* **ETCD_PORT** sets the TCP port on which to connect to the local etcd
-  daemon (default: *4001*)
-* **ETCD_PATH** sets the etcd directory where the logger announces
-  its configuration (default: */deis/logs*)
-* **ETCD_TTL** sets the time-to-live before etcd purges a configuration
-  value, in seconds (default: *10*)
-* **PORT** sets the TCP port on which the logger listens (default: *514*)
+```bash
+$ docker run deis/logger --help
+```
 
 ## License
 

logger/image/Dockerfile

@@ -1,6 +1,7 @@
 FROM ubuntu-debootstrap:14.04
 
-CMD ["/bin/logger"]
+ENTRYPOINT ["/bin/logger"]
+CMD ["--enable-publish"]
 EXPOSE 514
 
 ADD . /

logger/main.go

@@ -1,50 +1,67 @@
 package main
 
 import (
+	"flag"
+	"fmt"
 	"log"
 	"os"
 	"os/signal"
+	"strconv"
 	"syscall"
 	"time"
 
 	"github.com/coreos/go-etcd/etcd"
-
 	"github.com/deis/deis/logger/syslogd"
 )
 
-const (
-	timeout time.Duration = 10 * time.Second
-	ttl     time.Duration = timeout * 2
+var (
+	logAddr         string
+	logPort         int
+	enablePublish   bool
+	publishHost     string
+	publishPath     string
+	publishPort     string
+	publishInterval int
+	publishTTL      int
 )
 
-func main() {
-	host := getopt("HOST", "127.0.0.1")
-
-	etcdPort := getopt("ETCD_PORT", "4001")
-	etcdPath := getopt("ETCD_PATH", "/deis/logs")
+func init() {
+	flag.StringVar(&logAddr, "log-addr", "0.0.0.0", "bind address for the logger")
+	flag.IntVar(&logPort, "log-port", 514, "bind port for the logger")
+	flag.StringVar(&syslogd.LogRoot, "log-root", "/data/logs", "log path to store logs")
+	flag.BoolVar(&enablePublish, "enable-publish", false, "enable publishing to service discovery")
+	flag.StringVar(&publishHost, "publish-host", getopt("HOST", "127.0.0.1"), "service discovery hostname")
+	flag.IntVar(&publishInterval, "publish-interval", 10, "publish interval in seconds")
+	flag.StringVar(&publishPath, "publish-path", getopt("ETCD_PATH", "/deis/logs"), "path to publish host/port information")
+	flag.StringVar(&publishPort, "publish-port", getopt("ETCD_PORT", "4001"), "service discovery port")
+	flag.IntVar(&publishTTL, "publish-ttl", publishInterval*2, "publish TTL in seconds")
+}
 
-	externalPort := getopt("EXTERNAL_PORT", "514")
+func main() {
+	flag.Parse()
 
-	client := etcd.NewClient([]string{"http://" + host + ":" + etcdPort})
+	client := etcd.NewClient([]string{"http://" + publishHost + ":" + publishPort})
 
 	// Wait for terminating signal
 	exitChan := make(chan os.Signal, 2)
 	cleanupChan := make(chan bool)
 	signal.Notify(exitChan, syscall.SIGTERM, syscall.SIGINT)
 
-	go syslogd.Listen(exitChan, cleanupChan)
+	go syslogd.Listen(exitChan, cleanupChan, fmt.Sprintf("%s:%d", logAddr, logPort))
 
-	go publishService(client, host, etcdPath, externalPort, uint64(ttl.Seconds()))
+	if enablePublish {
+		go publishService(client, publishHost, publishPath, strconv.Itoa(logPort), uint64(time.Duration(publishTTL).Seconds()))
+	}
 
 	// Wait for the proper shutdown of the syslog server before exit
 	<-cleanupChan
 }
 
-func publishService(client *etcd.Client, host string, etcdPath string, externalPort string, ttl uint64) {
+func publishService(client *etcd.Client, host string, etcdPath string, port string, ttl uint64) {
 	for {
 		setEtcd(client, etcdPath+"/host", host, ttl)
-		setEtcd(client, etcdPath+"/port", externalPort, ttl)
-		time.Sleep(timeout)
+		setEtcd(client, etcdPath+"/port", port, ttl)
+		time.Sleep(time.Duration(publishInterval))
 	}
 }
 

logger/syslogd/syslogd.go

@@ -13,7 +13,7 @@ import (
 	"github.com/deis/deis/logger/drain"
 )
 
-const logRoot = "/data/logs"
+var LogRoot string
 
 type handler struct {
 	// To simplify implementation of our handler we embed helper
@@ -51,7 +51,7 @@ func getLogFile(message string) (io.Writer, error) {
 		return nil, fmt.Errorf("Could not find app name in message: %s", message)
 	}
 	appName := match[1]
-	filePath := path.Join(logRoot, appName+".log")
+	filePath := path.Join(LogRoot, appName+".log")
 	// check if file exists
 	exists, err := fileExists(filePath)
 	if err != nil {
@@ -97,19 +97,19 @@ func (h *handler) mainLoop() {
 }
 
 // Listen starts a new syslog server which runs until it receives a signal.
-func Listen(signalChan chan os.Signal, cleanupDone chan bool) {
+func Listen(signalChan chan os.Signal, cleanupDone chan bool, bindAddr string) {
 	fmt.Println("Starting syslog...")
-	// If logRoot doesn't exist, create it
+	// If LogRoot doesn't exist, create it
 	// equivalent to Python's `if not os.path.exists(filename)`
-	if _, err := os.Stat(logRoot); os.IsNotExist(err) {
-		if err = os.MkdirAll(logRoot, 0777); err != nil {
-			log.Fatalf("unable to create logRoot at %s", logRoot)
+	if _, err := os.Stat(LogRoot); os.IsNotExist(err) {
+		if err = os.MkdirAll(LogRoot, 0777); err != nil {
+			log.Fatalf("unable to create LogRoot at %s: %v", LogRoot, err)
 		}
 	}
 	// Create a server with one handler and run one listen gorutine
 	s := syslog.NewServer()
 	s.AddHandler(newHandler())
-	s.Listen("0.0.0.0:514")
+	s.Listen(bindAddr)
 	fmt.Println("Syslog server started...")
 	fmt.Println("deis-logger running")
 

logger/tests/logger_test.go

@@ -31,10 +31,11 @@ func TestLogger(t *testing.T) {
 			"--name", name,
 			"--rm",
 			"-p", port+":514/udp",
-			"-e", "EXTERNAL_PORT="+port,
-			"-e", "HOST="+host,
-			"-e", "ETCD_PORT="+etcdPort,
-			imageName)
+			imageName,
+			"--enable-publish",
+			"--log-port="+port,
+			"--publish-host="+host,
+			"--publish-port="+etcdPort)
 	}()
 	dockercli.PrintToStdout(t, stdout, stdoutPipe, "deis-logger running")
 	if err != nil {