package remoteexec import ( "bufio" "bytes" "fmt" "io" "io/ioutil" "log" "os" "strings" "time" helper "github.com/hashicorp/terraform/helper/ssh" "github.com/hashicorp/terraform/terraform" ) const ( // DefaultShebang is added at the top of the script file DefaultShebang = "#!/bin/sh" ) type ResourceProvisioner struct{} func (p *ResourceProvisioner) Apply(s *terraform.InstanceState, c *terraform.ResourceConfig) error { // Ensure the connection type is SSH if err := helper.VerifySSH(s); err != nil { return err } // Get the SSH configuration conf, err := helper.ParseSSHConfig(s) if err != nil { return err } // Collect the scripts scripts, err := p.collectScripts(c) if err != nil { return err } for _, s := range scripts { defer s.Close() } // Copy and execute each script if err := p.runScripts(conf, scripts); err != nil { return err } return nil } func (p *ResourceProvisioner) Validate(c *terraform.ResourceConfig) (ws []string, es []error) { num := 0 for name := range c.Raw { switch name { case "scripts": fallthrough case "script": fallthrough case "inline": num++ default: es = append(es, fmt.Errorf("Unknown configuration '%s'", name)) } } if num != 1 { es = append(es, fmt.Errorf("Must provide one of 'scripts', 'script' or 'inline' to remote-exec")) } return } // generateScript takes the configuration and creates a script to be executed // from the inline configs func (p *ResourceProvisioner) generateScript(c *terraform.ResourceConfig) (string, error) { lines := []string{DefaultShebang} command, ok := c.Config["inline"] if ok { switch cmd := command.(type) { case string: lines = append(lines, cmd) case []string: lines = append(lines, cmd...) case []interface{}: for _, l := range cmd { lStr, ok := l.(string) if ok { lines = append(lines, lStr) } else { return "", fmt.Errorf("Unsupported 'inline' type! Must be string, or list of strings.") } } default: return "", fmt.Errorf("Unsupported 'inline' type! Must be string, or list of strings.") } } lines = append(lines, "") return strings.Join(lines, "\n"), nil } // collectScripts is used to collect all the scripts we need // to execute in preparation for copying them. func (p *ResourceProvisioner) collectScripts(c *terraform.ResourceConfig) ([]io.ReadCloser, error) { // Check if inline _, ok := c.Config["inline"] if ok { script, err := p.generateScript(c) if err != nil { return nil, err } rc := ioutil.NopCloser(bytes.NewReader([]byte(script))) return []io.ReadCloser{rc}, nil } // Collect scripts var scripts []string s, ok := c.Config["script"] if ok { sStr, ok := s.(string) if !ok { return nil, fmt.Errorf("Unsupported 'script' type! Must be a string.") } scripts = append(scripts, sStr) } sl, ok := c.Config["scripts"] if ok { switch slt := sl.(type) { case []string: scripts = append(scripts, slt...) case []interface{}: for _, l := range slt { lStr, ok := l.(string) if ok { scripts = append(scripts, lStr) } else { return nil, fmt.Errorf("Unsupported 'scripts' type! Must be list of strings.") } } default: return nil, fmt.Errorf("Unsupported 'scripts' type! Must be list of strings.") } } // Open all the scripts var fhs []io.ReadCloser for _, s := range scripts { fh, err := os.Open(s) if err != nil { for _, fh := range fhs { fh.Close() } return nil, fmt.Errorf("Failed to open script '%s': %v", s, err) } fhs = append(fhs, fh) } // Done, return the file handles return fhs, nil } // runScripts is used to copy and execute a set of scripts func (p *ResourceProvisioner) runScripts(conf *helper.SSHConfig, scripts []io.ReadCloser) error { // Get the SSH client config config, err := helper.PrepareConfig(conf) if err != nil { return err } // Wait and retry until we establish the SSH connection var comm *helper.SSHCommunicator err = retryFunc(conf.TimeoutVal, func() error { host := fmt.Sprintf("%s:%d", conf.Host, conf.Port) comm, err = helper.New(host, config) return err }) if err != nil { return err } for _, script := range scripts { var cmd *helper.RemoteCmd err := retryFunc(conf.TimeoutVal, func() error { if err := comm.Upload(conf.ScriptPath, script); err != nil { return fmt.Errorf("Failed to upload script: %v", err) } cmd = &helper.RemoteCmd{ Command: fmt.Sprintf("chmod 0777 %s", conf.ScriptPath), } if err := comm.Start(cmd); err != nil { return fmt.Errorf( "Error chmodding script file to 0777 in remote "+ "machine: %s", err) } cmd.Wait() stdOutReader, stdOutWriter := io.Pipe() stdErrReader, stdErrWriter := io.Pipe() go streamLogs(stdOutReader, "stdout") go streamLogs(stdErrReader, "stderr") cmd = &helper.RemoteCmd{ Command: conf.ScriptPath, Stdout: stdOutWriter, Stderr: stdErrWriter, } if err := comm.Start(cmd); err != nil { return fmt.Errorf("Error starting script: %v", err) } return nil }) if err != nil { return err } cmd.Wait() if cmd.ExitStatus != 0 { return fmt.Errorf("Script exited with non-zero exit status: %d", cmd.ExitStatus) } } return nil } // retryFunc is used to retry a function for a given duration func retryFunc(timeout time.Duration, f func() error) error { finish := time.After(timeout) for { err := f() if err == nil { return nil } log.Printf("Retryable error: %v", err) select { case <-finish: return err case <-time.After(3 * time.Second): } } } // streamLogs is used to stream lines from stdout/stderr // of a remote command to log output for users. func streamLogs(r io.ReadCloser, name string) { defer r.Close() scanner := bufio.NewScanner(r) for scanner.Scan() { log.Printf("remote-exec: %s: %s", name, scanner.Text()) } if err := scanner.Err(); err != nil { return } }