- author
Catherine Devlin
- date
2010-02-20
- slides
- Sargon the Great
Founder of Akkadian Empire
- Command-Line Interface
Unlike the Akkadian Empire, the CLI will never die.
Also known as
- "Line-oriented command interpreter"
- "Command-line interface"
- "Shell"
- Accepts free text input at prompt
- Outputs lines of text
- (repeat)
- Bash, Korn, zsh
- Python shell
- screen
- Zork
- SQL clients: psql, SQL*Plus, mysql...
- ed
(ls
, grep
, ping
, etc.)
- Accept arguments at invocation
- execute
- terminate
Use sys.argv
, optparse
- Use entire (session) screen
- I/O is not line-by-line
- See
curses
,urwid
from cmd import Cmd
class Pirate(Cmd):
pass
pirate = Pirate()
pirate.cmdloop()
(Cmd) foo a b c
becomes
self.do_foo('a b c')
class Pirate(Cmd):
gold = 3
def do_loot(self, arg):
'Seize booty frrrom a passing ship.'
self.gold += 1
print('Now we gots {0} doubloons'
.format(self.gold))
def do_drink(self, arg):
'Drown your sorrrows in rrrum.'
self.gold -= 1
print('Now we gots {0} doubloons'
.format(self.gold))
self.preloop()
self.postloop()
self.precmd(line)
self.postcmd(stop, line)
def do_loot(self, arg):
'Seize booty from a passing ship.'
self.gold += 1
def do_drink(self, arg):
'Drown your sorrrows in rrrum.'
self.gold -= 1
def precmd(self, line):
self.initial_gold = self.gold
return line
def postcmd(self, stop, line):
if self.gold != self.initial_gold:
print('Now we gots {0} doubloons'
.format(self.gold))
def do_drink(self, arg):
'''Drown your sorrrows in rrrum.
drink [n] - drink [n] barrel[s] o' rum.'''
try:
self.gold -= int(arg)
except:
if arg:
print('''What's "{0}"? I'll take rrrum.'''
.format(arg))
self.gold -= 1
def postcmd(self, stop, line):
if self.gold != self.initial_gold:
print('Now we gots {0} doubloons'
.format(self.gold))
if self.gold < 0:
print("Off to debtorrr's prison.")
stop = True
return stop
def do_quit(self, arg):
print("Quiterrr!")
return True
prompt = 'arrr> '
def default(self, line):
print('What mean ye by "{0}"?'
.format(line))
- CmdLoop
- cly
- CMdO
- pycopia
- cmdlin
- cmd2
Convert cmd
app to cmd2
Python 3 compatible
(um, mostly)
Script files
Commands at invocation
Output redirection
Python
Transcript testing
- Abbreviated commands
- Shell commands
- Quitting
- Timing
- Echo
- Debug
default_to_shell = True
multilineCommands = ['sing']
terminators = Cmd.terminators + ['...']
songcolor = 'blue'
settable = Cmd.settable + 'songcolor Color to ``sing`` in (red/blue/green/cyan/magenta, bold, underline)'
Cmd.shortcuts.update({'~': 'sing'})
def do_sing(self, arg):
print(self.colorize(arg, self.songcolor))
options / flags
Quiet (suppress feedback)
BASH-style select
Parsing: terminators, suffixes
@options([make_option('--ho', type='int', default=2,
help="How often to chant 'ho'"),
make_option('-c', '--commas',
action="store_true",
help="Intersperse commas")])
def do_yo(self, arg, opts):
chant = ['yo'] + ['ho'] * opts.ho
separator = ', ' if opts.commas else ' '
chant = separator.join(chant)
print('{0} and a bottle of {1}'
.format(chant, arg))
cmd
-based app by Luca Canali @ CERN
Replacement for Oracle SQL*Plus
Now cmd2
-based; postgreSQL; MySQL
Gather info: Python
Store: postgresql
Report: html
import glob
import os.path
for fullfilename in glob.glob('/home/cat/proj/cmd2/*.py'):
(dirpath, fname) = os.path.split(fullfilename)
stats = os.stat(fullfilename)
binds['path'] = dirpath
binds['name'] = fname
binds['bytes'] = stats.st_size
cmd("""INSERT INTO cat.files (path, name, bytes)
VALUES (%(path)s, %(name)s, %(bytes)s)""")
quit()
- from
cmd2
: scripts, redirection, py, etc. - multiple connections
- UNIX: ls, cat, grep
- Special output