diff options
Diffstat (limited to 'docs/pycon2010/pycon2010.rst')
| -rw-r--r-- | docs/pycon2010/pycon2010.rst | 382 |
1 files changed, 0 insertions, 382 deletions
diff --git a/docs/pycon2010/pycon2010.rst b/docs/pycon2010/pycon2010.rst deleted file mode 100644 index 6c3af676..00000000 --- a/docs/pycon2010/pycon2010.rst +++ /dev/null @@ -1,382 +0,0 @@ -================================================ -Easy command-line interpreters with cmd and cmd2 -================================================ - -:author: Catherine Devlin -:date: 2010-02-20 -:slides: http://pypi.python.org/pypi/cmd2 - -Web 2.0 -======= - -.. image:: web-2-0-logos.gif - :height: 350px - -But first... -============ - -.. image:: sargon.jpg - :height: 250px - -.. image:: akkad.png - :height: 250px - -Sargon the Great - Founder of Akkadian Empire - -.. twenty-third century BC - -In between -========== - -.. image:: apple.jpg - :height: 250px - -Command-Line Interface - Unlike the Akkadian Empire, - the CLI will never die. - -Defining CLI -============ - -Also known as - -- "Line-oriented command interpreter" -- "Command-line interface" -- "Shell" - -1. Accepts free text input at prompt -2. Outputs lines of text -3. (repeat) - -Examples -======== - -.. class:: big - - * Bash, Korn, zsh - * Python shell - * screen - * Zork - * SQL clients: psql, SQL*\Plus, mysql... - * ed - -.. ``ed`` proves that CLI is sometimes the wrong answer. - -!= Command Line Utilities -========================= - -.. class:: big - - (``ls``, ``grep``, ``ping``, etc.) - - 1. Accept arguments at invocation - 2. execute - 3. terminate - - Use ``sys.argv``, ``optparse`` - -!="Text User Interface" -======================= - -* Use entire (session) screen -* I/O is *not* line-by-line -* See ``curses``, ``urwid`` - -.. image:: urwid.png - :height: 250px - - -Decide your priorities -====================== - -.. image:: strategy.png - :height: 350px - -A ``cmd`` app: pirate.py -======================== - -:: - - from cmd import Cmd - - class Pirate(Cmd): - pass - - pirate = Pirate() - pirate.cmdloop() - -.. Nothing here... but history and help - -.. ctrl-r for bash-style history - -Fundamental prrrinciple -======================= - -.. class:: huge - - ``(Cmd) foo a b c`` - - becomes - - ``self.do_foo('a b c')`` - -``do_``-methods: pirate2.py -=========================== - -:: - - 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)) - -.. do_methods; more help - -Hooks -===== - -.. image:: hook.jpg - :height: 250px - -:: - - self.preloop() - self.postloop() - self.precmd(line) - self.postcmd(stop, line) - -Hooks: pirate3.py -================= - -:: - - 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)) - -Arguments: pirate4.py -===================== - -:: - - 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 - -quitting: pirate5.py -==================== - -:: - - 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 - -prompts, defaults: pirate6.py -============================= - -:: - - prompt = 'arrr> ' - def default(self, line): - print('What mean ye by "{0}"?' - .format(line)) - -Other CLI packages -================== - -.. class:: big - - * CmdLoop - * cly - * CMdO - * pycopia - * cmdlin - * cmd2 - -Demo -==== - -.. class:: huge - - Convert ``cmd`` app to ``cmd2`` - -cmd2 -==== - -.. image:: schematic.png - :height: 350px - -As you wish, Guido -================== - -.. class:: huge - - Python 3 compatible - -(um, mostly) - -Absolutely free -=============== - -Script files - -Commands at invocation - -Output redirection - -Python - -Transcript testing - -But wait, there's more -====================== - - * Abbreviated commands - * Shell commands - * Quitting - * Timing - * Echo - * Debug - -Minor changes: pirate7.py -========================= - -:: - - 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)) - -Now how much would you pay? -=========================== - -options / flags - -Quiet (suppress feedback) - -BASH-style ``select`` - -Parsing: terminators, suffixes - -Options: pirate8.py -=================== - -:: - - @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)) - -Serious example: sqlpython -========================== - -.. class:: big - - ``cmd``-based app by Luca Canali @ CERN - - Replacement for Oracle SQL\*Plus - - Now ``cmd2``-based; postgreSQL; MySQL - -File reporter -============= - -.. class:: huge - - Gather info: Python - - Store: postgresql - - Report: html - -fileutil.py -=========== - -:: - - 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() - -sqlpython features -================== - -.. class:: big - - * from ``cmd2``: scripts, redirection, - py, etc. - * multiple connections - * UNIX: ls, cat, grep - * Special output - - -Thank you -========= - -.. class:: big - - http://pypi.python.org/pypi/cmd2 - - http://catherinedevlin.blogspot.com - - http://catherinedevlin.pythoneers.com - - |