Merge branch 'master' of ralfj.de:saartuer
[saartuer.git] / tyshell
1 #!/usr/bin/python3
2 import os
3 import readline
4 import shlex
5 import sys
6 import subprocess
7 import socket
8 import pwd
9 import grp
10 import traceback
11 from collections import namedtuple
12
13 tuerSock = "/run/tuer.sock"
14
15 # use a histfile
16 histfile = os.path.join(os.path.expanduser("~"), ".tyshellhist")
17 try:
18     readline.read_history_file(histfile)
19 except IOError:
20     pass
21 import atexit
22 atexit.register(readline.write_history_file, histfile)
23
24 # available commands
25 def helpcmd(c):
26         if (len(c) > 1):
27                 print(commands.get(c[1],(None,'Can\'t find help for command %s'%(c[1]))).helpstring)
28         else:
29                 print("Available commands: %s" % ", ".join(sorted(commands.keys())))
30                 print("Use 'help command' to get more information on the command 'command'")
31
32 def extcmd(cmd):
33         def run(c):
34                 ret = subprocess.call(cmd)
35                 if ret != 0:
36                         print("Command returned non-zero exit statis %d" % ret)
37         return run
38
39 def sendcmd(addr, cmd):
40         def run(c):
41                 print("206 Sending command %s..." % (cmd))
42                 s = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM)
43                 s.connect(addr)
44                 s.settimeout(60.0)
45                 s.send(cmd.encode())
46                 data = s.recv(256)
47                 s.close()
48                 print(data.decode('utf-8'))
49         return run
50
51 def exitcmd(c):
52         print("Bye")
53         return True
54
55 def whocmd(c):
56         for n in grp.getgrnam("tuer").gr_mem:
57                 p = pwd.getpwnam(n)
58                 print (p.pw_name, " - ", p.pw_gecos)
59
60 def alias (cmds, aliases):
61         for newname, oldname in aliases.items():
62                 cmds[newname] = cmds[oldname]
63         return cmds
64
65 CmdEntry = namedtuple('CmdEntry','function helpstring')
66
67 commands = alias({
68         'exit': CmdEntry(exitcmd, 'Quits this shell'),
69         'help': CmdEntry(helpcmd, 'Helps you getting to know the available commands'),
70         'unlock': CmdEntry(sendcmd(tuerSock, 'unlock'), 'Will try to unlock the apartment door'),
71         'buzz': CmdEntry(sendcmd(tuerSock, 'buzz'), 'Will buzz the buzzer for the street door'),
72         'who': CmdEntry(whocmd, 'Shows the list of people, who are allowed to control this system'),
73 },{
74         # aliases
75         'open': 'unlock',
76 })
77
78 def complete_command(cmd):
79         '''returns a list of commands (as strings) starting with cmd'''
80         return list(filter(lambda x: x.startswith(cmd), commands.keys()))
81 readline.set_completer(lambda cmd, num: (complete_command(cmd)+[None])[num]) # wrap complete_command for readline's weird completer API
82 readline.parse_and_bind("tab: complete") # run completion on tab
83
84 # input loop
85 print("Welcome to tyshell. Use help to see what you can do.")
86 while True:
87         try:
88                 command = input("$ ")
89         except EOFError:
90                 print()
91                 break
92         command = shlex.split(command)
93         if not len(command): continue
94         # find suiting commands
95         if command[0] in commands: # needed in case a complete command is a prefix of another one
96                 cmdoptions = [command[0]]
97         else:
98                 cmdoptions = complete_command(command[0])
99         # check how many we found
100         if len(cmdoptions) == 0: # no commands fit prefix
101                 print("Command %s not found. Use help." % command[0])
102         elif len(cmdoptions) == 1: # exactly one command fits (prefix)
103                 try:
104                         res = commands[cmdoptions[0]].function(command)
105                         if res: break
106                 except Exception as e:
107                         print("Error while executing %s: %s" % (command[0], str(e)))
108                         #print(traceback.format_exc())
109         else: # multiple commands fit the prefix
110                 print("Ambiguous command prefix, please choose one of the following:")
111                 print("\t", " ".join(cmdoptions))
112                 # TODO: put current "command[0]" into the shell for the next command, but such that it is deletable with backspace
113