TUN-528: Move cloudflared into a separate repo

cmd/cloudflared/service_template.go

@@ -0,0 +1,192 @@
+package main
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"text/template"
+
+	"github.com/mitchellh/go-homedir"
+)
+
+type ServiceTemplate struct {
+	Path     string
+	Content  string
+	FileMode os.FileMode
+}
+
+type ServiceTemplateArgs struct {
+	Path string
+}
+
+func (st *ServiceTemplate) ResolvePath() (string, error) {
+	resolvedPath, err := homedir.Expand(st.Path)
+	if err != nil {
+		return "", fmt.Errorf("error resolving path %s: %v", st.Path, err)
+	}
+	return resolvedPath, nil
+}
+
+func (st *ServiceTemplate) Generate(args *ServiceTemplateArgs) error {
+	tmpl, err := template.New(st.Path).Parse(st.Content)
+	if err != nil {
+		return fmt.Errorf("error generating %s template: %v", st.Path, err)
+	}
+	resolvedPath, err := st.ResolvePath()
+	if err != nil {
+		return err
+	}
+	var buffer bytes.Buffer
+	err = tmpl.Execute(&buffer, args)
+	if err != nil {
+		return fmt.Errorf("error generating %s: %v", st.Path, err)
+	}
+	fileMode := os.FileMode(0644)
+	if st.FileMode != 0 {
+		fileMode = st.FileMode
+	}
+	err = ioutil.WriteFile(resolvedPath, buffer.Bytes(), fileMode)
+	if err != nil {
+		return fmt.Errorf("error writing %s: %v", resolvedPath, err)
+	}
+	return nil
+}
+
+func (st *ServiceTemplate) Remove() error {
+	resolvedPath, err := st.ResolvePath()
+	if err != nil {
+		return err
+	}
+	err = os.Remove(resolvedPath)
+	if err != nil {
+		return fmt.Errorf("error deleting %s: %v", resolvedPath, err)
+	}
+	return nil
+}
+
+func runCommand(command string, args ...string) error {
+	cmd := exec.Command(command, args...)
+	stderr, err := cmd.StderrPipe()
+	if err != nil {
+		logger.WithError(err).Infof("error getting stderr pipe")
+		return fmt.Errorf("error getting stderr pipe: %v", err)
+	}
+	err = cmd.Start()
+	if err != nil {
+		logger.WithError(err).Infof("error starting %s", command)
+		return fmt.Errorf("error starting %s: %v", command, err)
+	}
+	commandErr, _ := ioutil.ReadAll(stderr)
+	if len(commandErr) > 0 {
+		logger.Errorf("%s: %s", command, commandErr)
+	}
+	err = cmd.Wait()
+	if err != nil {
+		logger.WithError(err).Infof("%s returned error", command)
+		return fmt.Errorf("%s returned with error: %v", command, err)
+	}
+	return nil
+}
+
+func ensureConfigDirExists(configDir string) error {
+	ok, err := fileExists(configDir)
+	if !ok && err == nil {
+		err = os.Mkdir(configDir, 0700)
+	}
+	return err
+}
+
+// openFile opens the file at path. If create is set and the file exists, returns nil, true, nil
+func openFile(path string, create bool) (file *os.File, exists bool, err error) {
+	expandedPath, err := homedir.Expand(path)
+	if err != nil {
+		return nil, false, err
+	}
+	if create {
+		fileInfo, err := os.Stat(expandedPath)
+		if err == nil && fileInfo.Size() > 0 {
+			return nil, true, nil
+		}
+		file, err = os.OpenFile(expandedPath, os.O_RDWR|os.O_CREATE, 0600)
+	} else {
+		file, err = os.Open(expandedPath)
+	}
+	return file, false, err
+}
+
+func copyCertificate(srcConfigDir, destConfigDir, credentialFile string) error {
+	destCredentialPath := filepath.Join(destConfigDir, credentialFile)
+	destFile, exists, err := openFile(destCredentialPath, true)
+	if err != nil {
+		return err
+	} else if exists {
+		// credentials already exist, do nothing
+		return nil
+	}
+	defer destFile.Close()
+
+	srcCredentialPath := filepath.Join(srcConfigDir, credentialFile)
+	srcFile, _, err := openFile(srcCredentialPath, false)
+	if err != nil {
+		return err
+	}
+	defer srcFile.Close()
+
+	// Copy certificate
+	_, err = io.Copy(destFile, srcFile)
+	if err != nil {
+		return fmt.Errorf("unable to copy %s to %s: %v", srcCredentialPath, destCredentialPath, err)
+	}
+
+	return nil
+}
+
+func copyCredentials(serviceConfigDir, defaultConfigDir, defaultConfigFile, defaultCredentialFile string) error {
+	if err := ensureConfigDirExists(serviceConfigDir); err != nil {
+		return err
+	}
+
+	if err := copyCertificate(defaultConfigDir, serviceConfigDir, defaultCredentialFile); err != nil {
+		return err
+	}
+
+	// Copy or create config
+	destConfigPath := filepath.Join(serviceConfigDir, defaultConfigFile)
+	destFile, exists, err := openFile(destConfigPath, true)
+	if err != nil {
+		logger.WithError(err).Infof("cannot open %s", destConfigPath)
+		return err
+	} else if exists {
+		// config already exists, do nothing
+		return nil
+	}
+	defer destFile.Close()
+
+	srcConfigPath := filepath.Join(defaultConfigDir, defaultConfigFile)
+	srcFile, _, err := openFile(srcConfigPath, false)
+	if err != nil {
+		fmt.Println("Your service needs a config file that at least specifies the hostname option.")
+		fmt.Println("Type in a hostname now, or leave it blank and create the config file later.")
+		fmt.Print("Hostname: ")
+		reader := bufio.NewReader(os.Stdin)
+		input, _ := reader.ReadString('\n')
+		if input == "" {
+			return err
+		}
+		fmt.Fprintf(destFile, "hostname: %s\n", input)
+	} else {
+		defer srcFile.Close()
+		_, err = io.Copy(destFile, srcFile)
+		if err != nil {
+			return fmt.Errorf("unable to copy %s to %s: %v", srcConfigPath, destConfigPath, err)
+		}
+		logger.Infof("Copied %s to %s", srcConfigPath, destConfigPath)
+	}
+
+	return nil
+}