Print version flag on every run

Moves handler code into separate file but retains same
package.

Changes watchdog to print version on start-up so that we can
grab this from logs. Version flag is also present for getting
additional information if needed from a user's published
container without running their function.

Signed-off-by: Alex Ellis (VMware) <alexellis2@gmail.com>

watchdog/handler.go

@@ -0,0 +1,307 @@
+// Copyright (c) Alex Ellis 2017. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+	"sync"
+	"time"
+
+	"github.com/openfaas/faas/watchdog/types"
+)
+
+var acceptingConnections bool
+
+// buildFunctionInput for a GET method this is an empty byte array.
+func buildFunctionInput(config *WatchdogConfig, r *http.Request) ([]byte, error) {
+	var res []byte
+	var requestBytes []byte
+	var err error
+
+	if r.Body == nil {
+		return res, nil
+	}
+	defer r.Body.Close()
+
+	if err != nil {
+		log.Println(err)
+		return res, err
+	}
+
+	requestBytes, err = ioutil.ReadAll(r.Body)
+	if config.marshalRequest {
+		marshalRes, marshalErr := types.MarshalRequest(requestBytes, &r.Header)
+		err = marshalErr
+		res = marshalRes
+	} else {
+		res = requestBytes
+	}
+
+	return res, err
+}
+
+func debugHeaders(source *http.Header, direction string) {
+	for k, vv := range *source {
+		fmt.Printf("[%s] %s=%s\n", direction, k, vv)
+	}
+}
+
+type requestInfo struct {
+	headerWritten bool
+}
+
+func pipeRequest(config *WatchdogConfig, w http.ResponseWriter, r *http.Request, method string) {
+	startTime := time.Now()
+
+	parts := strings.Split(config.faasProcess, " ")
+
+	ri := &requestInfo{}
+
+	if config.debugHeaders {
+		debugHeaders(&r.Header, "in")
+	}
+
+	log.Println("Forking fprocess.")
+
+	targetCmd := exec.Command(parts[0], parts[1:]...)
+
+	envs := getAdditionalEnvs(config, r, method)
+	if len(envs) > 0 {
+		targetCmd.Env = envs
+	}
+
+	writer, _ := targetCmd.StdinPipe()
+
+	var out []byte
+	var err error
+	var requestBody []byte
+
+	var wg sync.WaitGroup
+
+	wgCount := 2
+
+	var buildInputErr error
+	requestBody, buildInputErr = buildFunctionInput(config, r)
+	if buildInputErr != nil {
+		ri.headerWritten = true
+		w.WriteHeader(http.StatusBadRequest)
+		// I.e. "exit code 1"
+		w.Write([]byte(buildInputErr.Error()))
+
+		// Verbose message - i.e. stack trace
+		w.Write([]byte("\n"))
+		w.Write(out)
+
+		return
+	}
+
+	wg.Add(wgCount)
+
+	var timer *time.Timer
+
+	if config.execTimeout > 0*time.Second {
+		timer = time.NewTimer(config.execTimeout)
+
+		go func() {
+			<-timer.C
+			log.Printf("Killing process: %s\n", config.faasProcess)
+			if targetCmd != nil && targetCmd.Process != nil {
+				ri.headerWritten = true
+				w.WriteHeader(http.StatusRequestTimeout)
+
+				w.Write([]byte("Killed process.\n"))
+
+				val := targetCmd.Process.Kill()
+				if val != nil {
+					log.Printf("Killed process: %s - error %s\n", config.faasProcess, val.Error())
+				}
+			}
+		}()
+	}
+
+	// Write to pipe in separate go-routine to prevent blocking
+	go func() {
+		defer wg.Done()
+		writer.Write(requestBody)
+		writer.Close()
+	}()
+
+	if config.combineOutput {
+		// Read the output from stdout/stderr and combine into one variable for output.
+		go func() {
+			defer wg.Done()
+
+			out, err = targetCmd.CombinedOutput()
+		}()
+	} else {
+		go func() {
+			var b bytes.Buffer
+			targetCmd.Stderr = &b
+
+			defer wg.Done()
+
+			out, err = targetCmd.Output()
+			if b.Len() > 0 {
+				log.Printf("stderr: %s", b.Bytes())
+			}
+			b.Reset()
+		}()
+	}
+
+	wg.Wait()
+	if timer != nil {
+		timer.Stop()
+	}
+
+	if err != nil {
+		if config.writeDebug == true {
+			log.Printf("Success=%t, Error=%s\n", targetCmd.ProcessState.Success(), err.Error())
+			log.Printf("Out=%s\n", out)
+		}
+
+		if ri.headerWritten == false {
+			w.WriteHeader(http.StatusInternalServerError)
+			response := bytes.NewBufferString(err.Error())
+			w.Write(response.Bytes())
+			w.Write([]byte("\n"))
+			if len(out) > 0 {
+				w.Write(out)
+			}
+			ri.headerWritten = true
+		}
+		return
+	}
+
+	var bytesWritten string
+	if config.writeDebug == true {
+		os.Stdout.Write(out)
+	} else {
+		bytesWritten = fmt.Sprintf("Wrote %d Bytes", len(out))
+	}
+
+	if len(config.contentType) > 0 {
+		w.Header().Set("Content-Type", config.contentType)
+	} else {
+
+		// Match content-type of caller if no override specified.
+		clientContentType := r.Header.Get("Content-Type")
+		if len(clientContentType) > 0 {
+			w.Header().Set("Content-Type", clientContentType)
+		}
+	}
+
+	execDuration := time.Since(startTime).Seconds()
+	if ri.headerWritten == false {
+		w.Header().Set("X-Duration-Seconds", fmt.Sprintf("%f", execDuration))
+		ri.headerWritten = true
+		w.WriteHeader(200)
+		w.Write(out)
+	}
+
+	if config.debugHeaders {
+		header := w.Header()
+		debugHeaders(&header, "out")
+	}
+
+	if len(bytesWritten) > 0 {
+		log.Printf("%s - Duration: %f seconds", bytesWritten, execDuration)
+	} else {
+		log.Printf("Duration: %f seconds", execDuration)
+	}
+}
+
+func getAdditionalEnvs(config *WatchdogConfig, r *http.Request, method string) []string {
+	var envs []string
+
+	if config.cgiHeaders {
+		envs = os.Environ()
+
+		for k, v := range r.Header {
+			kv := fmt.Sprintf("Http_%s=%s", strings.Replace(k, "-", "_", -1), v[0])
+			envs = append(envs, kv)
+		}
+
+		envs = append(envs, fmt.Sprintf("Http_Method=%s", method))
+		envs = append(envs, fmt.Sprintf("Http_ContentLength=%d", r.ContentLength))
+
+		if config.writeDebug {
+			log.Println("Query ", r.URL.RawQuery)
+		}
+
+		if len(r.URL.RawQuery) > 0 {
+			envs = append(envs, fmt.Sprintf("Http_Query=%s", r.URL.RawQuery))
+		}
+
+		if config.writeDebug {
+			log.Println("Path ", r.URL.Path)
+		}
+
+		if len(r.URL.Path) > 0 {
+			envs = append(envs, fmt.Sprintf("Http_Path=%s", r.URL.Path))
+		}
+
+	}
+
+	return envs
+}
+
+func lockFilePresent() bool {
+	path := filepath.Join(os.TempDir(), ".lock")
+	if _, err := os.Stat(path); os.IsNotExist(err) {
+		return false
+	}
+	return true
+}
+
+func createLockFile() (string, error) {
+	path := filepath.Join(os.TempDir(), ".lock")
+	log.Printf("Writing lock-file to: %s\n", path)
+	writeErr := ioutil.WriteFile(path, []byte{}, 0660)
+	acceptingConnections = true
+
+	return path, writeErr
+}
+
+func makeHealthHandler() func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		switch r.Method {
+		case http.MethodGet:
+			if acceptingConnections == false || lockFilePresent() == false {
+				w.WriteHeader(http.StatusInternalServerError)
+				return
+			}
+
+			w.WriteHeader(http.StatusOK)
+			w.Write([]byte("OK"))
+			break
+		default:
+			w.WriteHeader(http.StatusMethodNotAllowed)
+		}
+	}
+}
+
+func makeRequestHandler(config *WatchdogConfig) func(http.ResponseWriter, *http.Request) {
+	return func(w http.ResponseWriter, r *http.Request) {
+		switch r.Method {
+		case
+			http.MethodPost,
+			http.MethodPut,
+			http.MethodDelete,
+			http.MethodGet:
+			pipeRequest(config, w, r, r.Method)
+			break
+		default:
+			w.WriteHeader(http.StatusMethodNotAllowed)
+
+		}
+	}
+}

watchdog/main.go

@@ -4,318 +4,31 @@
 package main
 
 import (
-	"bytes"
 	"context"
 	"flag"
 	"fmt"
-	"io/ioutil"
 	"log"
 	"net/http"
 	"os"
-	"os/exec"
 	"os/signal"
-	"path/filepath"
-	"strings"
-	"sync"
 	"syscall"
 	"time"
 
 	"github.com/openfaas/faas/watchdog/types"
 )
 
-var acceptingConnections bool
+var version bool
-
-// buildFunctionInput for a GET method this is an empty byte array.
-func buildFunctionInput(config *WatchdogConfig, r *http.Request) ([]byte, error) {
-	var res []byte
-	var requestBytes []byte
-	var err error
-
-	if r.Body == nil {
-		return res, nil
-	}
-	defer r.Body.Close()
-
-	if err != nil {
-		log.Println(err)
-		return res, err
-	}
-
-	requestBytes, err = ioutil.ReadAll(r.Body)
-	if config.marshalRequest {
-		marshalRes, marshalErr := types.MarshalRequest(requestBytes, &r.Header)
-		err = marshalErr
-		res = marshalRes
-	} else {
-		res = requestBytes
-	}
-
-	return res, err
-}
-
-func debugHeaders(source *http.Header, direction string) {
-	for k, vv := range *source {
-		fmt.Printf("[%s] %s=%s\n", direction, k, vv)
-	}
-}
-
-type requestInfo struct {
-	headerWritten bool
-}
-
-func pipeRequest(config *WatchdogConfig, w http.ResponseWriter, r *http.Request, method string) {
-	startTime := time.Now()
-
-	parts := strings.Split(config.faasProcess, " ")
-
-	ri := &requestInfo{}
-
-	if config.debugHeaders {
-		debugHeaders(&r.Header, "in")
-	}
-
-	log.Println("Forking fprocess.")
-
-	targetCmd := exec.Command(parts[0], parts[1:]...)
-
-	envs := getAdditionalEnvs(config, r, method)
-	if len(envs) > 0 {
-		targetCmd.Env = envs
-	}
-
-	writer, _ := targetCmd.StdinPipe()
-
-	var out []byte
-	var err error
-	var requestBody []byte
-
-	var wg sync.WaitGroup
-
-	wgCount := 2
-
-	var buildInputErr error
-	requestBody, buildInputErr = buildFunctionInput(config, r)
-	if buildInputErr != nil {
-		ri.headerWritten = true
-		w.WriteHeader(http.StatusBadRequest)
-		// I.e. "exit code 1"
-		w.Write([]byte(buildInputErr.Error()))
-
-		// Verbose message - i.e. stack trace
-		w.Write([]byte("\n"))
-		w.Write(out)
-
-		return
-	}
-
-	wg.Add(wgCount)
-
-	var timer *time.Timer
-
-	if config.execTimeout > 0*time.Second {
-		timer = time.NewTimer(config.execTimeout)
-
-		go func() {
-			<-timer.C
-			log.Printf("Killing process: %s\n", config.faasProcess)
-			if targetCmd != nil && targetCmd.Process != nil {
-				ri.headerWritten = true
-				w.WriteHeader(http.StatusRequestTimeout)
-
-				w.Write([]byte("Killed process.\n"))
-
-				val := targetCmd.Process.Kill()
-				if val != nil {
-					log.Printf("Killed process: %s - error %s\n", config.faasProcess, val.Error())
-				}
-			}
-		}()
-	}
-
-	// Write to pipe in separate go-routine to prevent blocking
-	go func() {
-		defer wg.Done()
-		writer.Write(requestBody)
-		writer.Close()
-	}()
-
-	if config.combineOutput {
-		// Read the output from stdout/stderr and combine into one variable for output.
-		go func() {
-			defer wg.Done()
-
-			out, err = targetCmd.CombinedOutput()
-		}()
-	} else {
-		go func() {
-			var b bytes.Buffer
-			targetCmd.Stderr = &b
-
-			defer wg.Done()
-
-			out, err = targetCmd.Output()
-			if b.Len() > 0 {
-				log.Printf("stderr: %s", b.Bytes())
-			}
-			b.Reset()
-		}()
-	}
-
-	wg.Wait()
-	if timer != nil {
-		timer.Stop()
-	}
-
-	if err != nil {
-		if config.writeDebug == true {
-			log.Printf("Success=%t, Error=%s\n", targetCmd.ProcessState.Success(), err.Error())
-			log.Printf("Out=%s\n", out)
-		}
-
-		if ri.headerWritten == false {
-			w.WriteHeader(http.StatusInternalServerError)
-			response := bytes.NewBufferString(err.Error())
-			w.Write(response.Bytes())
-			w.Write([]byte("\n"))
-			if len(out) > 0 {
-				w.Write(out)
-			}
-			ri.headerWritten = true
-		}
-		return
-	}
-
-	var bytesWritten string
-	if config.writeDebug == true {
-		os.Stdout.Write(out)
-	} else {
-		bytesWritten = fmt.Sprintf("Wrote %d Bytes", len(out))
-	}
-
-	if len(config.contentType) > 0 {
-		w.Header().Set("Content-Type", config.contentType)
-	} else {
-
-		// Match content-type of caller if no override specified.
-		clientContentType := r.Header.Get("Content-Type")
-		if len(clientContentType) > 0 {
-			w.Header().Set("Content-Type", clientContentType)
-		}
-	}
-
-	execDuration := time.Since(startTime).Seconds()
-	if ri.headerWritten == false {
-		w.Header().Set("X-Duration-Seconds", fmt.Sprintf("%f", execDuration))
-		ri.headerWritten = true
-		w.WriteHeader(200)
-		w.Write(out)
-	}
-
-	if config.debugHeaders {
-		header := w.Header()
-		debugHeaders(&header, "out")
-	}
-
-	if len(bytesWritten) > 0 {
-		log.Printf("%s - Duration: %f seconds", bytesWritten, execDuration)
-	} else {
-		log.Printf("Duration: %f seconds", execDuration)
-	}
-}
-
-func getAdditionalEnvs(config *WatchdogConfig, r *http.Request, method string) []string {
-	var envs []string
-
-	if config.cgiHeaders {
-		envs = os.Environ()
-
-		for k, v := range r.Header {
-			kv := fmt.Sprintf("Http_%s=%s", strings.Replace(k, "-", "_", -1), v[0])
-			envs = append(envs, kv)
-		}
-
-		envs = append(envs, fmt.Sprintf("Http_Method=%s", method))
-		envs = append(envs, fmt.Sprintf("Http_ContentLength=%d", r.ContentLength))
-
-		if config.writeDebug {
-			log.Println("Query ", r.URL.RawQuery)
-		}
-
-		if len(r.URL.RawQuery) > 0 {
-			envs = append(envs, fmt.Sprintf("Http_Query=%s", r.URL.RawQuery))
-		}
-
-		if config.writeDebug {
-			log.Println("Path ", r.URL.Path)
-		}
-
-		if len(r.URL.Path) > 0 {
-			envs = append(envs, fmt.Sprintf("Http_Path=%s", r.URL.Path))
-		}
-
-	}
-
-	return envs
-}
-
-func lockFilePresent() bool {
-	path := filepath.Join(os.TempDir(), ".lock")
-	if _, err := os.Stat(path); os.IsNotExist(err) {
-		return false
-	}
-	return true
-}
-
-func createLockFile() (string, error) {
-	path := filepath.Join(os.TempDir(), ".lock")
-	log.Printf("Writing lock-file to: %s\n", path)
-	writeErr := ioutil.WriteFile(path, []byte{}, 0660)
-	acceptingConnections = true
-
-	return path, writeErr
-}
-
-func makeHealthHandler() func(http.ResponseWriter, *http.Request) {
-	return func(w http.ResponseWriter, r *http.Request) {
-		switch r.Method {
-		case http.MethodGet:
-			if acceptingConnections == false || lockFilePresent() == false {
-				w.WriteHeader(http.StatusInternalServerError)
-				return
-			}
-
-			w.WriteHeader(http.StatusOK)
-			w.Write([]byte("OK"))
-			break
-		default:
-			w.WriteHeader(http.StatusMethodNotAllowed)
-		}
-	}
-}
-
-func makeRequestHandler(config *WatchdogConfig) func(http.ResponseWriter, *http.Request) {
-	return func(w http.ResponseWriter, r *http.Request) {
-		switch r.Method {
-		case
-			http.MethodPost,
-			http.MethodPut,
-			http.MethodDelete,
-			http.MethodGet:
-			pipeRequest(config, w, r, r.Method)
-			break
-		default:
-			w.WriteHeader(http.StatusMethodNotAllowed)
-
-		}
-	}
-}
-
-var (
-	version = flag.Bool("version", false, "Print the version and Git SHA")
-)
 
 func main() {
+	flag.BoolVar(&version, "version", false, "Print the version and exit")
+
 	flag.Parse()
+	printVersion()
+
+	if version == true {
+		return
+	}
+
 	acceptingConnections = false
 
 	osEnv := types.OsEnv{}
@@ -327,12 +40,6 @@ func main() {
 		return
 	}
 
-	if *version == true {
-		fmt.Printf("Commit: %v\n", GitCommit)
-		fmt.Printf("Version: %v\n", BuildVersion())
-		return
-	}
-
 	readTimeout := config.readTimeout
 	writeTimeout := config.writeTimeout
 
@@ -390,3 +97,12 @@ func listenUntilShutdown(shutdownTimeout time.Duration, s *http.Server) {
 
 	<-idleConnsClosed
 }
+
+func printVersion() {
+	sha := "unknown"
+	if len(GitCommit) > 0 {
+		sha = GitCommit
+	}
+
+	log.Printf("Version: %v\tSHA: %v\n", BuildVersion(), sha)
+}