Wait a bit more before starting to complain
[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                 while True:
47                         data = s.recv(256)
48                         if not len(data): break
49                         print(data.decode('utf-8'))
50                 s.close()
51         return run
52
53 def exitcmd(c):
54         print("Bye")
55         return True
56
57 def whocmd(c):
58         for n in grp.getgrnam("tuer").gr_mem:
59                 p = pwd.getpwnam(n)
60                 print (p.pw_name, " - ", p.pw_gecos)
61
62 def alias (cmds, aliases):
63         for newname, oldname in aliases.items():
64                 cmds[newname] = cmds[oldname]
65         return cmds
66
67 CmdEntry = namedtuple('CmdEntry','function helpstring')
68
69 commands = alias({
70         'exit': CmdEntry(exitcmd, 'Quits this shell'),
71         'help': CmdEntry(helpcmd, 'Helps you getting to know the available commands'),
72         'unlock': CmdEntry(sendcmd(tuerSock, 'unlock'), 'Will try to unlock the apartment door'),
73         'buzz': CmdEntry(sendcmd(tuerSock, 'buzz'), 'Will buzz the buzzer for the street door'),
74         'who': CmdEntry(whocmd, 'Shows the list of people, who are allowed to control this system'),
75 },{
76         # aliases
77         'open': 'unlock',
78 })
79
80 def complete_command(cmd):
81         '''returns a list of commands (as strings) starting with cmd'''
82         return list(filter(lambda x: x.startswith(cmd), commands.keys()))
83 readline.set_completer(lambda cmd, num: (complete_command(cmd)+[None])[num]) # wrap complete_command for readline's weird completer API
84 readline.parse_and_bind("tab: complete") # run completion on tab
85
86 # input loop
87 print("Welcome to tyshell. Use help to see what you can do.")
88 while True:
89         try:
90                 command = input("$ ")
91         except EOFError:
92                 print()
93                 break
94         command = shlex.split(command)
95         if not len(command): continue
96         # find suiting commands
97         if command[0] in commands: # needed in case a complete command is a prefix of another one
98                 cmdoptions = [command[0]]
99         else:
100                 cmdoptions = complete_command(command[0])
101         # check how many we found
102         if len(cmdoptions) == 0: # no commands fit prefix
103                 print("Command %s not found. Use help." % command[0])
104         elif len(cmdoptions) == 1: # exactly one command fits (prefix)
105                 try:
106                         res = commands[cmdoptions[0]].function(command)
107                         if res: break
108                 except Exception as e:
109                         print("Error while executing %s: %s" % (command[0], str(e)))
110                         #print(traceback.format_exc())
111         else: # multiple commands fit the prefix
112                 print("Ambiguous command prefix, please choose one of the following:")
113                 print("\t", " ".join(cmdoptions))
114                 # TODO: put current "command[0]" into the shell for the next command, but such that it is deletable with backspace
115