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# -*- test-case-name: twisted.test.test_usage -*-
# Copyright (c) 2001-2007 Twisted Matrix Laboratories.
# See LICENSE for details.
"""
twisted.python.usage is a module for parsing/handling the
command line of your program.
For information on how to use it, see
U{http://twistedmatrix.com/projects/core/documentation/howto/options.html},
or doc/howto/options.html in your Twisted directory.
"""
# System Imports
import os
import sys
import getopt
from os import path
# Sibling Imports
from twisted.python import reflect, text, util
class UsageError(Exception):
pass
error = UsageError
class CoerceParameter(object):
"""
Utility class that can corce a parameter before storing it.
"""
def __init__(self, options, coerce):
"""
@param options: parent Options object
@param coerce: callable used to coerce the value.
"""
self.options = options
self.coerce = coerce
self.doc = getattr(self.coerce, 'coerceDoc', '')
def dispatch(self, parameterName, value):
"""
When called in dispatch, do the coerce for C{value} and save the
returned value.
"""
if value is None:
raise UsageError("Parameter '%s' requires an argument."
% (parameterName,))
try:
value = self.coerce(value)
except ValueError, e:
raise UsageError("Parameter type enforcement failed: %s" % (e,))
self.options.opts[parameterName] = value
class Options(dict):
"""
An option list parser class
C{optFlags} and C{optParameters} are lists of available parameters
which your program can handle. The difference between the two
is the 'flags' have an on(1) or off(0) state (off by default)
whereas 'parameters' have an assigned value, with an optional
default. (Compare '--verbose' and '--verbosity=2')
optFlags is assigned a list of lists. Each list represents
a flag parameter, as so::
| optFlags = [['verbose', 'v', 'Makes it tell you what it doing.'],
| ['quiet', 'q', 'Be vewy vewy quiet.']]
As you can see, the first item is the long option name
(prefixed with '--' on the command line), followed by the
short option name (prefixed with '-'), and the description.
The description is used for the built-in handling of the
--help switch, which prints a usage summary.
C{optParameters} is much the same, except the list also contains
a default value::
| optParameters = [['outfile', 'O', 'outfile.log', 'Description...']]
A coerce function can also be specified as the last element: it will be
called with the argument and should return the value that will be stored
for the option. This function can have a C{coerceDoc} attribute which
will be appended to the documentation of the option.
subCommands is a list of 4-tuples of (command name, command shortcut,
parser class, documentation). If the first non-option argument found is
one of the given command names, an instance of the given parser class is
instantiated and given the remainder of the arguments to parse and
self.opts[command] is set to the command name. For example::
| subCommands = [
| ['inquisition', 'inquest', InquisitionOptions,
| 'Perform an inquisition'],
| ['holyquest', 'quest', HolyQuestOptions,
| 'Embark upon a holy quest']
| ]
In this case, C{"<program> holyquest --horseback --for-grail"} will cause
C{HolyQuestOptions} to be instantiated and asked to parse
C{['--horseback', '--for-grail']}. Currently, only the first sub-command
is parsed, and all options following it are passed to its parser. If a
subcommand is found, the subCommand attribute is set to its name and the
subOptions attribute is set to the Option instance that parses the
remaining options. If a subcommand is not given to parseOptions,
the subCommand attribute will be None. You can also mark one of
the subCommands to be the default.
| defaultSubCommand = 'holyquest'
In this case, the subCommand attribute will never be None, and
the subOptions attribute will always be set.
If you want to handle your own options, define a method named
C{opt_paramname} that takes C{(self, option)} as arguments. C{option}
will be whatever immediately follows the parameter on the
command line. Options fully supports the mapping interface, so you
can do things like C{'self["option"] = val'} in these methods.
Advanced functionality is covered in the howto documentation,
available at
U{http://twistedmatrix.com/projects/core/documentation/howto/options.html},
or doc/howto/options.html in your Twisted directory.
"""
subCommand = None
defaultSubCommand = None
parent = None
def __init__(self):
super(Options, self).__init__()
self.opts = self
self.defaults = {}
# These are strings/lists we will pass to getopt
self.longOpt = []
self.shortOpt = ''
self.docs = {}
self.synonyms = {}
self._dispatch = {}
collectors = [
self._gather_flags,
self._gather_parameters,
self._gather_handlers,
]
for c in collectors:
(longOpt, shortOpt, docs, settings, synonyms, dispatch) = c()
self.longOpt.extend(longOpt)
self.shortOpt = self.shortOpt + shortOpt
self.docs.update(docs)
self.opts.update(settings)
self.defaults.update(settings)
self.synonyms.update(synonyms)
self._dispatch.update(dispatch)
def __hash__(self):
"""
Define a custom hash function so that Options instances can be used
as dictionary keys. This is an internal feature used to implement
the parser. Do not rely on it in application code.
"""
return int(id(self) % sys.maxint)
def opt_help(self):
"""
Display this help and exit.
"""
print self.__str__()
sys.exit(0)
def opt_version(self):
from twisted import copyright
print "Twisted version:", copyright.version
sys.exit(0)
#opt_h = opt_help # this conflicted with existing 'host' options.
def parseOptions(self, options=None):
"""
The guts of the command-line parser.
"""
if options is None:
options = sys.argv[1:]
try:
opts, args = getopt.getopt(options,
self.shortOpt, self.longOpt)
except getopt.error, e:
raise UsageError(str(e))
for opt, arg in opts:
if opt[1] == '-':
opt = opt[2:]
else:
opt = opt[1:]
optMangled = opt
if optMangled not in self.synonyms:
optMangled = opt.replace("-", "_")
if optMangled not in self.synonyms:
raise UsageError("No such option '%s'" % (opt,))
optMangled = self.synonyms[optMangled]
if isinstance(self._dispatch[optMangled], CoerceParameter):
self._dispatch[optMangled].dispatch(optMangled, arg)
else:
self._dispatch[optMangled](optMangled, arg)
if (getattr(self, 'subCommands', None)
and (args or self.defaultSubCommand is not None)):
if not args:
args = [self.defaultSubCommand]
sub, rest = args[0], args[1:]
for (cmd, short, parser, doc) in self.subCommands:
if sub == cmd or sub == short:
self.subCommand = cmd
self.subOptions = parser()
self.subOptions.parent = self
self.subOptions.parseOptions(rest)
break
else:
raise UsageError("Unknown command: %s" % sub)
else:
try:
self.parseArgs(*args)
except TypeError:
raise UsageError("Wrong number of arguments.")
self.postOptions()
def postOptions(self):
"""
I am called after the options are parsed.
Override this method in your subclass to do something after
the options have been parsed and assigned, like validate that
all options are sane.
"""
def parseArgs(self):
"""
I am called with any leftover arguments which were not options.
Override me to do something with the remaining arguments on
the command line, those which were not flags or options. e.g.
interpret them as a list of files to operate on.
Note that if there more arguments on the command line
than this method accepts, parseArgs will blow up with
a getopt.error. This means if you don't override me,
parseArgs will blow up if I am passed any arguments at
all!
"""
def _generic_flag(self, flagName, value=None):
if value not in ('', None):
raise UsageError("Flag '%s' takes no argument."
" Not even \"%s\"." % (flagName, value))
self.opts[flagName] = 1
def _gather_flags(self):
"""
Gather up boolean (flag) options.
"""
longOpt, shortOpt = [], ''
docs, settings, synonyms, dispatch = {}, {}, {}, {}
flags = []
reflect.accumulateClassList(self.__class__, 'optFlags', flags)
for flag in flags:
long, short, doc = util.padTo(3, flag)
if not long:
raise ValueError("A flag cannot be without a name.")
docs[long] = doc
settings[long] = 0
if short:
shortOpt = shortOpt + short
synonyms[short] = long
longOpt.append(long)
synonyms[long] = long
dispatch[long] = self._generic_flag
return longOpt, shortOpt, docs, settings, synonyms, dispatch
def _gather_parameters(self):
"""
Gather options which take a value.
"""
longOpt, shortOpt = [], ''
docs, settings, synonyms, dispatch = {}, {}, {}, {}
parameters = []
reflect.accumulateClassList(self.__class__, 'optStrings',
parameters)
if parameters:
import warnings
warnings.warn("Options.optStrings is deprecated, "
"please use optParameters instead.", stacklevel=2)
reflect.accumulateClassList(self.__class__, 'optParameters',
parameters)
synonyms = {}
for parameter in parameters:
long, short, default, doc, paramType = util.padTo(5, parameter)
if not long:
raise ValueError("A parameter cannot be without a name.")
docs[long] = doc
settings[long] = default
if short:
shortOpt = shortOpt + short + ':'
synonyms[short] = long
longOpt.append(long + '=')
synonyms[long] = long
if paramType is not None:
dispatch[long] = CoerceParameter(self, paramType)
else:
dispatch[long] = CoerceParameter(self, str)
return longOpt, shortOpt, docs, settings, synonyms, dispatch
def _gather_handlers(self):
"""
Gather up options with their own handler methods.
"""
longOpt, shortOpt = [], ''
docs, settings, synonyms, dispatch = {}, {}, {}, {}
dct = {}
reflect.addMethodNamesToDict(self.__class__, dct, "opt_")
for name in dct.keys():
method = getattr(self, 'opt_'+name)
takesArg = not flagFunction(method, name)
prettyName = name.replace('_', '-')
doc = getattr(method, '__doc__', None)
if doc:
## Only use the first line.
#docs[name] = doc.split('\n')[0]
docs[prettyName] = doc
else:
docs[prettyName] = self.docs.get(prettyName)
synonyms[prettyName] = prettyName
# A little slight-of-hand here makes dispatching much easier
# in parseOptions, as it makes all option-methods have the
# same signature.
if takesArg:
fn = lambda name, value, m=method: m(value)
else:
# XXX: This won't raise a TypeError if it's called
# with a value when it shouldn't be.
fn = lambda name, value=None, m=method: m()
dispatch[prettyName] = fn
if len(name) == 1:
shortOpt = shortOpt + name
if takesArg:
shortOpt = shortOpt + ':'
else:
if takesArg:
prettyName = prettyName + '='
longOpt.append(prettyName)
reverse_dct = {}
# Map synonyms
for name in dct.keys():
method = getattr(self, 'opt_' + name)
if method not in reverse_dct:
reverse_dct[method] = []
reverse_dct[method].append(name)
cmpLength = lambda a, b: cmp(len(a), len(b))
for method, names in reverse_dct.items():
if len(names) < 2:
continue
names_ = names[:]
names_.sort(cmpLength)
longest = names_.pop()
for name in names_:
synonyms[name] = longest
return longOpt, shortOpt, docs, settings, synonyms, dispatch
def __str__(self):
return self.getSynopsis() + '\n' + self.getUsage(width=None)
def getSynopsis(self):
"""
Returns a string containing a description of these options and how to
pass them to the executed file.
"""
default = "%s%s" % (path.basename(sys.argv[0]),
(self.longOpt and " [options]") or '')
if self.parent is None:
default = "Usage: %s%s" % (path.basename(sys.argv[0]),
(self.longOpt and " [options]") or '')
else:
default = '%s' % ((self.longOpt and "[options]") or '')
synopsis = getattr(self, "synopsis", default)
synopsis = synopsis.rstrip()
if self.parent is not None:
synopsis = ' '.join((self.parent.getSynopsis(),
self.parent.subCommand, synopsis))
return synopsis
def getUsage(self, width=None):
# If subOptions exists by now, then there was probably an error while
# parsing its options.
if hasattr(self, 'subOptions'):
return self.subOptions.getUsage(width=width)
if not width:
width = int(os.environ.get('COLUMNS', '80'))
if hasattr(self, 'subCommands'):
cmdDicts = []
for (cmd, short, parser, desc) in self.subCommands:
cmdDicts.append(
{'long': cmd,
'short': short,
'doc': desc,
'optType': 'command',
'default': None
})
chunks = docMakeChunks(cmdDicts, width)
commands = 'Commands:\n' + ''.join(chunks)
else:
commands = ''
longToShort = {}
for key, value in self.synonyms.items():
longname = value
if (key != longname) and (len(key) == 1):
longToShort[longname] = key
else:
if longname not in longToShort:
longToShort[longname] = None
else:
pass
optDicts = []
for opt in self.longOpt:
if opt[-1] == '=':
optType = 'parameter'
opt = opt[:-1]
else:
optType = 'flag'
optDicts.append(
{'long': opt,
'short': longToShort[opt],
'doc': self.docs[opt],
'optType': optType,
'default': self.defaults.get(opt, None),
'dispatch': self._dispatch.get(opt, None)
})
if not (getattr(self, "longdesc", None) is None):
longdesc = self.longdesc
else:
import __main__
if getattr(__main__, '__doc__', None):
longdesc = __main__.__doc__
else:
longdesc = ''
if longdesc:
longdesc = ('\n' +
'\n'.join(text.wordWrap(longdesc, width)).strip()
+ '\n')
if optDicts:
chunks = docMakeChunks(optDicts, width)
s = "Options:\n%s" % (''.join(chunks))
else:
s = "Options: None\n"
return s + longdesc + commands
#def __repr__(self):
# XXX: It'd be cool if we could return a succinct representation
# of which flags and options are set here.
def docMakeChunks(optList, width=80):
"""
Makes doc chunks for option declarations.
Takes a list of dictionaries, each of which may have one or more
of the keys 'long', 'short', 'doc', 'default', 'optType'.
Returns a list of strings.
The strings may be multiple lines,
all of them end with a newline.
"""
# XXX: sanity check to make sure we have a sane combination of keys.
maxOptLen = 0
for opt in optList:
optLen = len(opt.get('long', ''))
if optLen:
if opt.get('optType', None) == "parameter":
# these take up an extra character
optLen = optLen + 1
maxOptLen = max(optLen, maxOptLen)
colWidth1 = maxOptLen + len(" -s, -- ")
colWidth2 = width - colWidth1
# XXX - impose some sane minimum limit.
# Then if we don't have enough room for the option and the doc
# to share one line, they can take turns on alternating lines.
colFiller1 = " " * colWidth1
optChunks = []
seen = {}
for opt in optList:
if opt.get('short', None) in seen or opt.get('long', None) in seen:
continue
for x in opt.get('short', None), opt.get('long', None):
if x is not None:
seen[x] = 1
optLines = []
comma = " "
if opt.get('short', None):
short = "-%c" % (opt['short'],)
else:
short = ''
if opt.get('long', None):
long = opt['long']
if opt.get("optType", None) == "parameter":
long = long + '='
long = "%-*s" % (maxOptLen, long)
if short:
comma = ","
else:
long = " " * (maxOptLen + len('--'))
if opt.get('optType', None) == 'command':
column1 = ' %s ' % long
else:
column1 = " %2s%c --%s " % (short, comma, long)
if opt.get('doc', ''):
doc = opt['doc'].strip()
else:
doc = ''
if (opt.get("optType", None) == "parameter") \
and not (opt.get('default', None) is None):
doc = "%s [default: %s]" % (doc, opt['default'])
if (opt.get("optType", None) == "parameter") \
and opt.get('dispatch', None) is not None:
d = opt['dispatch']
if isinstance(d, CoerceParameter) and d.doc:
doc = "%s. %s" % (doc, d.doc)
if doc:
column2_l = text.wordWrap(doc, colWidth2)
else:
column2_l = ['']
optLines.append("%s%s\n" % (column1, column2_l.pop(0)))
for line in column2_l:
optLines.append("%s%s\n" % (colFiller1, line))
optChunks.append(''.join(optLines))
return optChunks
def flagFunction(method, name=None):
reqArgs = method.im_func.func_code.co_argcount
if reqArgs > 2:
raise UsageError('Invalid Option function for %s' %
(name or method.func_name))
if reqArgs == 2:
# argName = method.im_func.func_code.co_varnames[1]
return 0
return 1
def portCoerce(value):
"""
Coerce a string value to an int port number, and checks the validity.
"""
value = int(value)
if value < 0 or value > 65535:
raise ValueError("Port number not in range: %s" % (value,))
return value
portCoerce.coerceDoc = "Must be an int between 0 and 65535."
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