cli.py

#!/usr/bin/env python
#coding=utf8

'''
CloudControl CLI class
'''

import os, os.path
import sys
import socket
import ssl
import threading
import subprocess
import ConfigParser
import re

from cccli import printer, command, version, debug
from cccli.command import Command
from cccli.clierror import *
from sjrpc.core.exceptions import *
from sjrpc.client import SimpleRpcClient
from sjrpc.utils import RpcHandler, ConnectionProxy, pure

class Cli(object):
    def __init__(self, settings):
        self.isinteractive = sys.stderr.isatty() and sys.stdin.isatty()
        self.settings = settings
        self.prompt = "> "
        self.rpc = None
        self.alias = Alias()
        self.history = History(self)

    def start(self, line=""):
        '''Start a CLI'''
        # not interactive is command line
        if line:
            self.isinteractive = False
        # start readline and load history
        if self.isinteractive:
            import readline
            self.readline = readline
            self.history.load(self.settings.get("history", ""))
            self.history.maxsize(self.settings.get("hsize", None))
        # load alias
        self.alias.load(self.settings.get("alias", ""))
        printer.debug("Alias: %s"%self.alias)
        # Connecting
        self._connect()
        # authentifications
        self._auth()
        # run parsing args
        if line:
            self._parse_line(line)
        else:
            self._shell()
        self.history.save(self.settings.get("history", ""))


    def _connect(self):
        printer.debug("Connecting...")
        rpcc = SimpleRpcClient.from_addr(self.settings["server"],
                                         self.settings["port"],
                                         enable_ssl=True,
                                         default_handler=CliHandler(),
                                         on_disconnect="quit",
                                         timeout=self.settings["timeout"]
                                        )
        rpcc.start(daemonize=True)
        self.rpc = ConnectionProxy(rpcc)

    def _auth(self):
        printer.debug("Authenticating...")
        if self.rpc.authentify(self.settings["login"], self.settings["pass"]):
            printer.debug("Authenticated.")
        else:
            printer.fatal("Autentification failed!")

    def _shell(self):
        '''Shell parser'''
        while True:
            try:
                line = raw_input(self.prompt)
                self._parse_line(line)
            except EOFError:
                printer.out("")
                break
            except SystemExit:
                break
            except KeyboardInterrupt:
                printer.out("")
        printer.out("Tcho!")

    def _parse_line(self, line):
        '''Parse a line (more than one command)'''
        for cmd in line.split(";"):
            if (cmd.strip() == "" or cmd[0] == "#"):
                continue
            elif (cmd[0] == "!"):
                p = subprocess.Popen(cmd[1:], close_fds=True, shell=True)
                p.wait()
                ret = p.returncode
            elif (cmd[0] == "?"):
                Command(["help"], self).call()
            else:
                self._parse_command(cmd)

    def _parse_command(self, cmd):
        try:
            # lex command
            argv = self._lex_argv(cmd)
            # alias subs
            if argv[0] in self.alias:
                argv[0] = self.alias[argv[0]]
            # execute command
            Command(argv, self).call()
        except BadArgument, e:
            if str(e):
                printer.error("Bad argument: %s."%str(e))
            else:
                printer.error("Bad argument.")
            usage = Command.usage(argv[0])
            if usage != "":
                printer.out("usage: %s."%usage)
        except BadCommand, e:
            if str(e):
                printer.error("command: %s."%str(e))
            else:
                printer.error("No command: %s."%argv[0])
        except RpcError, e:
            if debug: raise
            printer.error("sjRPC: %s"%str(e))
        except Exception, e:
            if debug: raise
            printer.error("%s: %s."%(argv[0], str(e)))

    def _lex_argv(self, string):
        '''Lex command argument'''
        return string.split(" ")

class Alias(dict):
    ''' Alias wrapper'''
    def load(self, filename):
        '''load alias from file'''
        if os.access(filename, os.R_OK):
            fparser = ConfigParser.SafeConfigParser()
            fparser.read(filename)
            if fparser.has_section("alias"):
                self.clear()
                self.update(fparser.items("alias"))

    def save(self, filename):
        '''save alias on file'''
        if os.access(filename, os.R_OK or os.W_OK):
            fparser = ConfigParser.SafeConfigParser()
            fparser.read(filename)
            fparser.remove_section("alias")
            fparser.add_section("alias")
            for n,v in self.items():
                fparser.set("alias", n, v)
            fparser.write(open(filename, "w"))

class History(object):
    '''History class'''
    def __init__(self, cli):
        self.cli = cli

    def __nonzero__(self):
        return not self.cli.readline is None

    def __getattribute__(self, name):
        r = object.__getattribute__(self, "cli")
        if name == "cli":
            return r
        if r.readline is None:
            return lambda *a,**k: None
        return object.__getattribute__(self, name)

    def __iter__(self):
        for i in range(1, len(self)):
            yield self.cli.readline.get_history_item(i)

    def __len__(self):
        return self.cli.readline.get_current_history_length()

    def load(self, path):
        '''Load history from a file'''
        try:
            self.cli.readline.read_history_file(path)
        except IOError:
            pass

    def save(self, path):
        '''Save history into path'''
        try:
            self.cli.readline.write_history_file(path)
        except IOError:
            pass

    def maxsize(self, size=None):
        '''Set or return max history size'''
        if size is not None:
            self.cli.readline.set_history_length(size)
        return self.cli.readline.get_history_length()

    def removelast(self):
        '''Remove last history line'''
        self.cli.readline.remove_history_item(self.cli.readline.get_current_history_length())

    def clear(self):
        '''Clear history'''
        self.cli.readline.clear_history()


class CliHandler(RpcHandler):
    '''Handle RPC incoming request'''

    @pure
    def get_tags(self, tags=()):
        if "version" in tags:
            return { "version": version }

    @pure
    def quit(self, rpc=None):
        printer.fatal("Disconnected from server!")