Merge lp:~mvo/snappy/snappy-console into lp:~snappy-dev/snappy/snappy-moved-to-github

[Michael Vogt]

Add new "snappy shell" command.

This is a bit of a proof-of-concept and needs additional work to package the golang-liner package for debian.

It will add a new "snappy console" command that will run a minimal readline like console to run commands.

[John Lenton (chipaca)]

Lovely. Obviously needs work, but lovely. You want to land this? I'm +1 for it.

review: Approve

[Leo Arias (elopio)]

One detail to take into account is that liner has 13.7% of test coverage.
We should unit test our code and increase the liner unit test coverage, or cover both with integration or functional tests. Or well, there's always the option of just accepting the risk of adding untested dependencies to our project.

[Michael Vogt (mvo)]

@Leo Thanks! I haven't actually checked the coverage for liner, that is a good point indeed. I looked into the coverage problems and it seems a lot of it is because of the way it deals with input, I pushed https://github.com/mvo5/liner/commit/485491f62cf2779cd5cc60a05101472576c597ec that covers some more input classes as a starting point. It seems improving coverage is relatively straightforward. Fwiw, I'm not sure the alternatives are better, AFAICS the C libreadline (which is what the others are based on) is not unit tested at all.

[Leo Arias (elopio)]

A small detail found by vet:

$ go vet ./cmd/snappy/
cmd/snappy/cmd_console.go:96: unreachable code
exit status 1

review: Needs Fixing

[Leo Arias (elopio)]

Also, lint doesn't like it.

Lint complains:
cmd/snappy/cmd_console.go:76:10: if block ends with a return statement, so drop this else and outdent its block (move short variable declaration to its own line if necessary)

review: Needs Fixing

[Michael Vogt (mvo)]

Thanks! I fixed the vet/lint issues.

[Michael Vogt (mvo)]

I put this up again, during the Lexington sprint we talked about that we want a snappy console experience. However, feel free to reject if you feel like its not mature enough yet.

[lp:~mvo/snappy/snappy-console]

524. By Michael Vogt on 2015-09-18

merged lp:snappy

[Michael Vogt (mvo)]

All vet/lint issues should be resolved, so I will approve based on the approve from John in the first comment.

review: Approve

=== added file 'cmd/snappy/cmd_console.go'
--- cmd/snappy/cmd_console.go	1970-01-01 00:00:00 +0000
+++ cmd/snappy/cmd_console.go	2015-09-18 05:57:08 +0000
@@ -0,0 +1,165 @@
+// -*- Mode: Go; indent-tabs-mode: t -*-
+
+/*
+ * Copyright (C) 2014-2015 Canonical Ltd
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package main
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/peterh/liner"
+
+	"launchpad.net/snappy/logger"
+)
+
+// for testing
+var stdout io.Writer = os.Stdout
+
+type cmdConsole struct {
+	repl          *liner.State
+	extraCommands []consoleCommand
+}
+
+func init() {
+	_, err := parser.AddCommand("console",
+		"Run snappy console interface",
+		"Run snappy console interface",
+		&cmdConsole{})
+	if err != nil {
+		logger.Panicf("Unable to console: %v", err)
+	}
+}
+
+func (x *cmdConsole) Execute(args []string) error {
+	return x.doConsole()
+}
+
+type consoleCommand struct {
+	name string
+	fn   func(line string) error
+}
+
+func (x *cmdConsole) snappyCompleter(line string) (c []string) {
+	// FIXME: add smartz and also complete arguments of
+	//        commands
+	for _, cmd := range parser.Commands() {
+		if strings.HasPrefix(cmd.Name, strings.ToLower(line)) {
+			c = append(c, cmd.Name)
+		}
+	}
+	for _, cmd := range x.extraCommands {
+		if strings.HasPrefix(cmd.name, line) {
+			c = append(c, cmd.name)
+		}
+	}
+
+	return c
+}
+
+func (x *cmdConsole) initConsole() error {
+	// FIXME: add history (ReadHistory/WriteHistory)
+
+	x.extraCommands = []consoleCommand{
+		{"help", x.doHelp},
+		{"shell", x.doShell},
+	}
+
+	x.repl = liner.NewLiner()
+	x.repl.SetCompleter(x.snappyCompleter)
+
+	return nil
+}
+
+func (x *cmdConsole) CloseConsole() {
+	x.repl.Close()
+}
+
+func (x *cmdConsole) PrintWelcomeMessage() {
+	fmt.Println("Welcome to the snappy console")
+	fmt.Println("Type 'help' for help")
+	fmt.Println("Type 'shell' for entering a shell")
+}
+
+func (x *cmdConsole) doShell(line string) error {
+	// restore terminal for the shell
+	x.CloseConsole()
+	defer x.initConsole()
+
+	sh := os.Getenv("SHELL")
+	if sh == "" {
+		sh = "/bin/sh"
+	}
+	cmd := exec.Command(sh)
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	if err := cmd.Run(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (x *cmdConsole) doHelp(line string) error {
+	line = strings.TrimPrefix(line, "help")
+	line = strings.TrimSpace(line)
+	parser.Active = nil
+	// find subcmd
+	for _, cmd := range parser.Commands() {
+		if strings.HasPrefix(line, cmd.Name) {
+			parser.Active = cmd
+			break
+		}
+	}
+	parser.WriteHelp(stdout)
+
+	return nil
+}
+
+func (x *cmdConsole) doConsole() error {
+	x.initConsole()
+	defer x.CloseConsole()
+	x.PrintWelcomeMessage()
+
+outer:
+	for {
+		line, err := x.repl.Prompt("> ")
+		if err != nil {
+			return err
+		}
+		x.repl.AppendHistory(line)
+
+		for _, cmd := range x.extraCommands {
+			if strings.HasPrefix(line, cmd.name) {
+				if err := cmd.fn(line); err != nil {
+					fmt.Println(err)
+				}
+				continue outer
+			}
+		}
+
+		if _, err = parser.ParseArgs(strings.Fields(line)); err != nil {
+			fmt.Println(err)
+		}
+
+	}
+}

=== added file 'cmd/snappy/cmd_console_test.go'
--- cmd/snappy/cmd_console_test.go	1970-01-01 00:00:00 +0000
+++ cmd/snappy/cmd_console_test.go	2015-09-18 05:57:08 +0000
@@ -0,0 +1,57 @@
+// -*- Mode: Go; indent-tabs-mode: t -*-
+
+/*
+ * Copyright (C) 2014-2015 Canonical Ltd
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 3 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+package main
+
+import (
+	"bytes"
+
+	. "gopkg.in/check.v1"
+)
+
+func (s *CmdTestSuite) TestCmdConsoleCompleter(c *C) {
+	// setup
+	x := cmdConsole{}
+
+	err := x.initConsole()
+	c.Assert(err, IsNil)
+
+	// from cmdline parser
+	c.Check(x.snappyCompleter("hw-"), DeepEquals, []string{"hw-assign", "hw-info", "hw-unassign"})
+
+	// extra consoleCommand
+	c.Check(x.snappyCompleter("he"), DeepEquals, []string{"help"})
+	c.Check(x.snappyCompleter("help"), DeepEquals, []string{"help"})
+}
+
+func (s *CmdTestSuite) TestDoHelpGeneric(c *C) {
+	stdout = bytes.NewBuffer(nil)
+
+	x := cmdConsole{}
+	x.doHelp("")
+	c.Assert(stdout.(*bytes.Buffer).String(), Matches, `(?sm).*Available commands:`)
+}
+
+func (s *CmdTestSuite) TestDoHelpSet(c *C) {
+	stdout = bytes.NewBuffer(nil)
+
+	x := cmdConsole{}
+	x.doHelp("set")
+	c.Assert(stdout.(*bytes.Buffer).String(), Matches, `(?sm).*Set properties of system or package`)
+}

=== modified file 'debian/control'
--- debian/control	2015-09-14 19:04:47 +0000
+++ debian/control	2015-09-18 05:57:08 +0000
@@ -15,6 +15,7 @@
                golang-go-flags-dev,
                golang-go.crypto-dev,
                golang-goconfigparser-dev,
+               golang-go-liner-dev,
                golang-pb-dev,
                golang-uboot-go-dev,
                golang-yaml.v2-dev,

=== modified file 'dependencies.tsv'
--- dependencies.tsv	2015-09-16 12:04:05 +0000
+++ dependencies.tsv	2015-09-18 05:57:08 +0000
@@ -6,6 +6,7 @@
 github.com/gosexy/gettext	git	98b7b91596d20b96909e6b60d57411547dd9959c	2013-02-21T11:21:43Z
 github.com/jessevdk/go-flags	git	1acbbaff2f347c412a0c7884873bd72cc9c1f5b4	2015-08-16T10:05:21Z
 github.com/mvo5/goconfigparser	git	26426272dda20cc76aa1fa44286dc743d2972fe8	2015-02-12T09:37:50Z
+github.com/peterh/liner	git	1bb0d1c1a25ed393d8feb09bab039b2b1b1fbced	2015-04-02T04:04:07Z
 github.com/mvo5/uboot-go	git	361f6ebcbb54f389d15dc9faefa000e996ba3e37	2015-07-22T06:53:46Z
 golang.org/x/crypto	git	60052bd85f2d91293457e8811b0cf26b773de469	2015-06-22T23:34:07Z
 gopkg.in/check.v1	git	64131543e7896d5bcc6bd5a76287eb75ea96c673	2014-10-24T13:38:53Z