Move template functions to separate file

Author: jwilder

docker-gen.go

@@ -1,25 +1,21 @@
 package main
 
 import (
-	"bytes"
 	"encoding/json"
 	"flag"
 	"fmt"
 	"github.com/BurntSushi/toml"
 	"github.com/fsouza/go-dockerclient"
 	"io"
-	"io/ioutil"
 	"net"
 	"net/http"
 	"net/http/httputil"
 	"os"
 	"os/exec"
 	"os/signal"
-	"path/filepath"
 
 	"strings"
 	"syscall"
-	"text/template"
 )
 
 var (
@@ -76,91 +72,10 @@ func (r *RuntimeContainer) Equals(o RuntimeContainer) bool {
 	return r.ID == o.ID && r.Image == o.Image
 }
 
-func groupBy(entries []*RuntimeContainer, key string) map[string][]*RuntimeContainer {
-	groups := make(map[string][]*RuntimeContainer)
-	for _, v := range entries {
-		value := deepGet(*v, key)
-		if value != nil {
-			groups[value.(string)] = append(groups[value.(string)], v)
-		}
-	}
-	return groups
-}
-
-func contains(a map[string]string, b string) bool {
-	if _, ok := a[b]; ok {
-		return true
-	}
-	return false
-}
-
 func usage() {
 	println("Usage: docker-gen [-config file] [-watch=false] [-notify=\"restart xyz\"] <template> [<dest>]")
 }
 
-func generateFile(config Config, containers []*RuntimeContainer) bool {
-	templatePath := config.Template
-	tmpl, err := template.New(filepath.Base(templatePath)).Funcs(template.FuncMap{
-		"contains": contains,
-		"groupBy":  groupBy,
-	}).ParseFiles(templatePath)
-	if err != nil {
-		panic(err)
-	}
-
-	filteredContainers := []*RuntimeContainer{}
-	if config.OnlyExposed {
-		for _, container := range containers {
-			if len(container.Addresses) > 0 {
-				filteredContainers = append(filteredContainers, container)
-			}
-		}
-	} else {
-		filteredContainers = containers
-	}
-
-	tmpl = tmpl
-	dest := os.Stdout
-	if config.Dest != "" {
-		dest, err = ioutil.TempFile("", "docker-gen")
-		defer dest.Close()
-		if err != nil {
-			fmt.Printf("unable to create temp file: %s\n", err)
-			os.Exit(1)
-		}
-	}
-
-	var buf bytes.Buffer
-	multiwriter := io.MultiWriter(dest, &buf)
-	err = tmpl.ExecuteTemplate(multiwriter, filepath.Base(templatePath), containers)
-	if err != nil {
-		fmt.Printf("template error: %s\n", err)
-	}
-
-	if config.Dest != "" {
-
-		contents := []byte{}
-		if _, err := os.Stat(config.Dest); err == nil {
-			contents, err = ioutil.ReadFile(config.Dest)
-			if err != nil {
-				fmt.Printf("unable to compare current file contents: %s: %s\n", config.Dest, err)
-				os.Exit(1)
-			}
-		}
-
-		if bytes.Compare(contents, buf.Bytes()) != 0 {
-			err = os.Rename(dest.Name(), config.Dest)
-			if err != nil {
-				fmt.Printf("unable to create dest file %s: %s\n", config.Dest, err)
-				os.Exit(1)
-			}
-			return true
-		}
-		return false
-	}
-	return true
-}
-
 func newConn() (*httputil.ClientConn, error) {
 	conn, err := net.Dial("unix", "/var/run/docker.sock")
 	if err != nil {

template.go

@@ -0,0 +1,92 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"text/template"
+)
+
+func groupBy(entries []*RuntimeContainer, key string) map[string][]*RuntimeContainer {
+	groups := make(map[string][]*RuntimeContainer)
+	for _, v := range entries {
+		value := deepGet(*v, key)
+		if value != nil {
+			groups[value.(string)] = append(groups[value.(string)], v)
+		}
+	}
+	return groups
+}
+
+func contains(item map[string]string, key string) bool {
+	if _, ok := item[key]; ok {
+		return true
+	}
+	return false
+}
+
+func generateFile(config Config, containers []*RuntimeContainer) bool {
+	templatePath := config.Template
+	tmpl, err := template.New(filepath.Base(templatePath)).Funcs(template.FuncMap{
+		"contains": contains,
+		"groupBy":  groupBy,
+	}).ParseFiles(templatePath)
+	if err != nil {
+		panic(err)
+	}
+
+	filteredContainers := []*RuntimeContainer{}
+	if config.OnlyExposed {
+		for _, container := range containers {
+			if len(container.Addresses) > 0 {
+				filteredContainers = append(filteredContainers, container)
+			}
+		}
+	} else {
+		filteredContainers = containers
+	}
+
+	tmpl = tmpl
+	dest := os.Stdout
+	if config.Dest != "" {
+		dest, err = ioutil.TempFile("", "docker-gen")
+		defer dest.Close()
+		if err != nil {
+			fmt.Printf("unable to create temp file: %s\n", err)
+			os.Exit(1)
+		}
+	}
+
+	var buf bytes.Buffer
+	multiwriter := io.MultiWriter(dest, &buf)
+	err = tmpl.ExecuteTemplate(multiwriter, filepath.Base(templatePath), containers)
+	if err != nil {
+		fmt.Printf("template error: %s\n", err)
+	}
+
+	if config.Dest != "" {
+
+		contents := []byte{}
+		if _, err := os.Stat(config.Dest); err == nil {
+			contents, err = ioutil.ReadFile(config.Dest)
+			if err != nil {
+				fmt.Printf("unable to compare current file contents: %s: %s\n", config.Dest, err)
+				os.Exit(1)
+			}
+		}
+
+		if bytes.Compare(contents, buf.Bytes()) != 0 {
+			err = os.Rename(dest.Name(), config.Dest)
+			if err != nil {
+				fmt.Printf("unable to create dest file %s: %s\n", config.Dest, err)
+				os.Exit(1)
+			}
+			return true
+		}
+		return false
+	}
+	return true
+}