generalize "write" -- file output + shell pipes

commands.go

@@ -245,6 +245,53 @@ func cmdLoad(jq *JQShell, flags *CmdFlags) error {
 	return nil
 }
 
+func cmdPipeShell(jq *JQShell, flags *CmdFlags) error {
+	flags.ArgSet("command")
+	color := flags.Bool("-color", false, "pass colorized json to command")
+	err := flags.Parse(nil)
+	if IsHelp(err) {
+		return nil
+	}
+	if err != nil {
+		return err
+	}
+	args := flags.Args()
+	if len(args) == 0 {
+		return fmt.Errorf("missing command")
+	}
+	shell := os.Getenv("SHELL")
+	if shell == "" {
+		shell = "bash"
+	}
+	shcmd := []string{shell, "-c", args[0]}
+	cmd := exec.Command(shell, shcmd[1:]...)
+	cmd.Stderr = os.Stderr
+	cmd.Stdout = os.Stdout
+	stdin, err := cmd.StdinPipe()
+	if err != nil {
+		return fmt.Errorf("creating pipe: %v", err)
+	}
+	err = cmd.Start()
+	waiterr := make(chan error, 1)
+	go func() {
+		waiterr <- cmd.Wait()
+		stdin.Close()
+	}()
+	if err != nil {
+		return ExecError{shcmd, err}
+	}
+	_, _, err = cmdWrite_io(jq, stdin, *color, nil)
+	if err != nil {
+		<-waiterr
+		return err
+	}
+	err = <-waiterr
+	if err != nil {
+		return ExecError{shcmd, err}
+	}
+	return nil
+}
+
 func cmdWrite(jq *JQShell, flags *CmdFlags) error {
 	flags.ArgSet("[filename]")
 	err := flags.Parse(nil)
@@ -256,40 +303,64 @@ func cmdWrite(jq *JQShell, flags *CmdFlags) error {
 	}
 	args := flags.Args()
 	if len(args) == 0 {
-		r, err := jq.Input()
-		if err != nil {
-			return err
-		}
-		defer r.Close()
-		w, errch := Page(nil)
-		select {
-		case err := <-errch:
-			return err
-		default:
-			break
-		}
-		pageerr := make(chan error, 1)
-		stop := make(chan struct{})
-		go func() {
-			err := <-errch
-			close(stop)
-			if err != nil {
-				pageerr <- err
-			}
-			close(pageerr)
-		}()
-		_, _, err = Execute(w, os.Stderr, r, stop, jq.bin, jq.Stack)
-		w.Close()
+		return cmdWrite_page(jq)
+	}
+	return cmdWrite_file(jq, args[0])
+}
+
+func cmdWrite_page(jq *JQShell) error {
+	w, errch := Page(nil)
+	select {
+	case err := <-errch:
+		return err
+	default:
+		break
+	}
+	pageerr := make(chan error, 1)
+	stop := make(chan struct{})
+	go func() {
+		err := <-errch
+		close(stop)
 		if err != nil {
-			return ExecError{[]string{"jq"}, err}
-		}
-		pageErr := <-pageerr
-		if pageErr != nil {
-			jq.log("pager: ", pageErr)
+			pageerr <- err
 		}
-		return nil
+		close(pageerr)
+	}()
+	_, _, err := cmdWrite_io(jq, w, true, stop)
+	if err != nil {
+		return err
 	}
-	return fmt.Errorf("file output not allowed")
+	pageErr := <-pageerr
+	if pageErr != nil {
+		jq.log("pager: ", pageErr)
+	}
+	return nil
+}
+
+func cmdWrite_file(jq *JQShell, filename string) error {
+	f, err := os.Create(filename)
+	if err != nil {
+		return err
+	}
+	nout, _, err := cmdWrite_io(jq, f, false, nil)
+	if err == nil {
+		jq.Log.Printf("%d bytes written to %q", nout, filename)
+	}
+	return err
+}
+
+func cmdWrite_io(jq *JQShell, w io.WriteCloser, color bool, stop chan struct{}) (int64, int64, error) {
+	r, err := jq.Input()
+	if err != nil {
+		return 0, 0, err
+	}
+	defer r.Close()
+	defer w.Close()
+	nout, nerr, err := Execute(w, os.Stderr, r, stop, jq.bin, color, jq.Stack)
+	if err != nil {
+		return nout, nerr, ExecError{[]string{"jq"}, err}
+	}
+	return nout, nerr, err
 }
 
 func cmdRaw(jq *JQShell, flags *CmdFlags) error {

jq.go

@@ -137,13 +137,18 @@ func (w *writeCounter) Write(bs []byte) (int, error) {
 	return n, err
 }
 
-func Execute(outw, errw io.Writer, in io.Reader, stop <-chan struct{}, jq string, s *JQStack) (int64, int64, error) {
+func Execute(outw, errw io.Writer, in io.Reader, stop <-chan struct{}, jq string, color bool, s *JQStack) (int64, int64, error) {
 	if jq == "" {
 		jq = "jq"
 	}
 	outcounter := &writeCounter{0, outw}
 	errcounter := &writeCounter{0, errw}
-	cmd := exec.Command(jq, "-C", JoinFilter(s)) // TODO test if stdout is a terminal
+	var args []string
+	if color {
+		args = append(args, "--color-output")
+	}
+	args = append(args, JoinFilter(s))
+	cmd := exec.Command(jq, args...)
 	cmd.Stdin = in
 	cmd.Stdout = outcounter
 	cmd.Stderr = errcounter

jqsh.go

@@ -184,6 +184,7 @@ func NewJQShell(bin string, sh ShellReader) *JQShell {
 	jq.lib.Register("script", JQShellCommandFunc(cmdScript))
 	jq.lib.Register("load", JQShellCommandFunc(cmdLoad))
 	jq.lib.Register("exec", JQShellCommandFunc(cmdExec))
+	jq.lib.Register("sh", JQShellCommandFunc(cmdPipeShell))
 	jq.lib.Register("write", JQShellCommandFunc(cmdWrite))
 	jq.lib.Register("raw", JQShellCommandFunc(cmdRaw))
 	jq.lib.Register("quit", JQShellCommandFunc(cmdQuit))
@@ -299,7 +300,7 @@ func (jq *JQShell) loop() {
 					jq.Log.Print(err)
 				} else if len(cmd.cmd) == 0 {
 					jq.Log.Println("empty command")
-				} else if cmd.cmd[0] != "write" && cmd.cmd[0] != "raw" && cmd.cmd[0] != "filter" && cmd.cmd[0] != "script" && cmd.cmd[0] != "help" {
+				} else if cmd.cmd[0] != "write" && cmd.cmd[0] != "raw" && cmd.cmd[0] != "filter" && cmd.cmd[0] != "script" && cmd.cmd[0] != "help" && cmd.cmd[0] != "sh" {
 					// TODO clean this up. (cmdPushInteractive, cmdPeek)
 					err := jq.execute([]string{"write"}, nil)
 					if err != nil {