def _fix_compat_issue29(function):
#
# TODO: remove before 1.0 release (will break backwards compatibility)
#
if getattr(function, ATTR_EXPECTS_NAMESPACE_OBJECT, False):
# a modern decorator is used, no compatibility issues
return function
if getattr(function, ATTR_INFER_ARGS_FROM_SIGNATURE, False):
# wrapped in outdated decorator but it implies modern behaviour
return function
# Okay, now we've got either a modern-style function (plain signature)
# or an old-style function which implicitly expects a namespace object.
# It's very likely that in the latter case the function accepts one and
# only argument named "args". If so, we simply wrap this function in
# @expects_obj and issue a warning.
spec = compat.getargspec(function)
if spec.args in [['arg'], ['args'], ['self', 'arg'], ['self', 'args']]:
# this is it -- a classic old-style function, goddamnit.
# no checking *args and **kwargs because they are unlikely to matter.
import warnings
warnings.warn(
'Function {0} is very likely to be old-style, i.e. '
'implicitly expects a namespace object. This behaviour '
'is deprecated. Wrap it in @expects_obj decorator or '
'convert to plain signature.'.format(function.__name__),
DeprecationWarning)
setattr(function, ATTR_EXPECTS_NAMESPACE_OBJECT, True)
return function
def _fix_compat_issue29(function):
#
# TODO: remove before 1.0 release (will break backwards compatibility)
#
if getattr(function, ATTR_EXPECTS_NAMESPACE_OBJECT, False):
# a modern decorator is used, no compatibility issues
return function
if getattr(function, ATTR_INFER_ARGS_FROM_SIGNATURE, False):
# wrapped in outdated decorator but it implies modern behaviour
return function
# Okay, now we've got either a modern-style function (plain signature)
# or an old-style function which implicitly expects a namespace object.
# It's very likely that in the latter case the function accepts one and
# only argument named "args". If so, we simply wrap this function in
# @expects_obj and issue a warning.
spec = compat.getargspec(function)
if spec.args in [['arg'], ['args'], ['self', 'arg'], ['self', 'args']]:
# this is it -- a classic old-style function, goddamnit.
# no checking *args and **kwargs because they are unlikely to matter.
import warnings
warnings.warn('Function {0} is very likely to be old-style, i.e. '
'implicitly expects a namespace object. This behaviour '
'is deprecated. Wrap it in @expects_obj decorator or '
'convert to plain signature.'.format(function.__name__),
DeprecationWarning)
setattr(function, ATTR_EXPECTS_NAMESPACE_OBJECT, True)
return function
def get_arg_spec(function):
"""Returns argument specification for given function. Omits special
arguments of instance methods (`self`) and static methods (usually `cls`
or something like this).
"""
spec = compat.getargspec(function)
if inspect.ismethod(function):
spec = spec._replace(args=spec.args[1:])
return spec
def get_arg_spec(function):
"""
Returns argument specification for given function. Omits special
arguments of instance methods (`self`) and static methods (usually `cls`
or something like this).
"""
spec = compat.getargspec(function)
if inspect.ismethod(function):
spec = spec._replace(args=spec.args[1:])
return spec
def get_arg_names(function):
"""Returns argument names for given function. Omits special arguments
of instance methods (`self`) and static methods (usually `cls` or something
like this).
"""
spec = compat.getargspec(function)
names = spec.args
if not names:
return []
if inspect.ismethod(function):
return names[1:]
else:
return names
def get_arg_names(function):
"""Returns argument names for given function. Omits special arguments
of instance methods (`self`) and static methods (usually `cls` or something
like this).
"""
spec = compat.getargspec(function)
names = spec.args
if not names:
return []
if inspect.ismethod(function):
return names[1:]
else:
return names
def _get_args_from_signature(function):
if getattr(function, ATTR_EXPECTS_NAMESPACE_OBJECT, False):
return
spec = compat.getargspec(function)
names = get_arg_names(function)
kwargs = dict(zip(*[reversed(x) for x in (names, spec.defaults or [])]))
if sys.version_info < (3,0):
annotations = {}
else:
annotations = dict((k,v) for k,v in function.__annotations__.items()
if isinstance(v, str))
# define the list of conflicting option strings
# (short forms, i.e. single-character ones)
chars = [a[0] for a in names]
char_counts = dict((char, chars.count(char)) for char in set(chars))
conflicting_opts = tuple(char for char in char_counts
if 1 < char_counts[char])
for name in names:
flags = [] # name_or_flags
akwargs = {} # keyword arguments for add_argument()
if name in annotations:
# help message: func(a : "b") -> add_argument("a", help="b")
akwargs.update(help=annotations.get(name))
if name in kwargs:
akwargs.update(default=kwargs.get(name))
flags = ('-{0}'.format(name[0]), '--{0}'.format(name))
if name.startswith(conflicting_opts):
# remove short name
flags = flags[1:]
else:
# positional argument
flags = (name,)
# cmd(foo_bar) -> add_argument('foo-bar')
flags = tuple(x.replace('_', '-') for x in flags)
yield dict(option_strings=flags, **akwargs)
if spec.varargs:
# *args
yield dict(option_strings=[spec.varargs], nargs='*')
def _get_args_from_signature(function):
if getattr(function, ATTR_EXPECTS_NAMESPACE_OBJECT, False):
return
spec = compat.getargspec(function)
names = get_arg_names(function)
kwargs = dict(zip(*[reversed(x) for x in (names, spec.defaults or [])]))
if sys.version_info < (3, 0):
annotations = {}
else:
annotations = dict((k, v) for k, v in function.__annotations__.items()
if isinstance(v, str))
# define the list of conflicting option strings
# (short forms, i.e. single-character ones)
chars = [a[0] for a in names]
char_counts = dict((char, chars.count(char)) for char in set(chars))
conflicting_opts = tuple(char for char in char_counts
if 1 < char_counts[char])
for name in names:
flags = [] # name_or_flags
akwargs = {} # keyword arguments for add_argument()
if name in annotations:
# help message: func(a : "b") -> add_argument("a", help="b")
akwargs.update(help=annotations.get(name))
if name in kwargs:
akwargs.update(default=kwargs.get(name))
flags = ('-{0}'.format(name[0]), '--{0}'.format(name))
if name.startswith(conflicting_opts):
# remove short name
flags = flags[1:]
else:
# positional argument
flags = (name, )
# cmd(foo_bar) -> add_argument('foo-bar')
flags = tuple(x.replace('_', '-') for x in flags)
yield dict(option_strings=flags, **akwargs)
if spec.varargs:
# *args
yield dict(option_strings=[spec.varargs], nargs='*')
def _call():
# Actually call the function
if getattr(args.function, ATTR_EXPECTS_NAMESPACE_OBJECT, False):
result = args.function(args)
else:
# namespace -> dictionary
_flat_key = lambda key: key.replace('-', '_')
all_input = dict((_flat_key(k), v) for k,v in vars(args).items())
# filter the namespace variables so that only those expected by the
# actual function will pass
spec = compat.getargspec(args.function)
names = get_arg_names(args.function)
positional = [all_input[k] for k in names]
keywords = {}
# *args
if spec.varargs:
positional += getattr(args, spec.varargs)
# **kwargs
varkw = getattr(spec, 'varkw', getattr(spec, 'keywords', []))
if varkw:
not_kwargs = ['function'] + spec.args + [spec.varargs]
extra = [k for k in vars(args) if k not in not_kwargs]
for k in extra:
keywords[k] = getattr(args, k)
result = args.function(*positional, **keywords)
# Yield the results
if isinstance(result, (GeneratorType, list, tuple)):
# yield each line ASAP, convert CommandError message to a line
for line in result:
yield line
else:
# yield non-empty non-iterable result as a single line
if result is not None:
yield result
def _call():
# Actually call the function
if getattr(args.function, ATTR_EXPECTS_NAMESPACE_OBJECT, False):
result = args.function(args)
else:
# namespace -> dictionary
_flat_key = lambda key: key.replace('-', '_')
all_input = dict((_flat_key(k), v) for k, v in vars(args).items())
# filter the namespace variables so that only those expected by the
# actual function will pass
spec = compat.getargspec(args.function)
names = get_arg_names(args.function)
positional = [all_input[k] for k in names]
keywords = {}
# *args
if spec.varargs:
positional += getattr(args, spec.varargs)
# **kwargs
varkw = getattr(spec, 'varkw', getattr(spec, 'keywords', []))
if varkw:
not_kwargs = ['function'] + spec.args + [spec.varargs]
extra = [k for k in vars(args) if k not in not_kwargs]
for k in extra:
keywords[k] = getattr(args, k)
result = args.function(*positional, **keywords)
# Yield the results
if isinstance(result, (GeneratorType, list, tuple)):
# yield each line ASAP, convert CommandError message to a line
for line in result:
yield line
else:
# yield non-empty non-iterable result as a single line
if result is not None:
yield result
def set_default_command(parser, function):
""" Sets default command (i.e. a function) for given parser.
If `parser.description` is empty and the function has a docstring,
it is used as the description.
.. note::
An attempt to set default command to a parser which already has
subparsers (e.g. added with :func:`~argh.assembling.add_commands`)
results in a `RuntimeError`.
.. note::
If there are both explicitly declared arguments (e.g. via
:func:`~argh.decorators.arg`) and ones inferred from the function
signature (e.g. via :func:`~argh.decorators.command`), declared ones
will be merged into inferred ones. If an argument does not conform
function signature, `ValueError` is raised.
.. note::
If the parser was created with ``add_help=True`` (which is by default),
option name ``-h`` is silently removed from any argument.
"""
if parser._subparsers:
raise RuntimeError('Cannot set default command to a parser with '
'existing subparsers')
function = _fix_compat_issue29(function)
spec = compat.getargspec(function)
declared_args = getattr(function, ATTR_ARGS, [])
inferred_args = list(_get_args_from_signature(function))
if inferred_args and declared_args:
# We've got a mixture of declared and inferred arguments
# FIXME this is an ugly hack for preserving order
dests = []
inferred_dict = {}
for x in inferred_args:
dest = _get_dest(parser, x)
dests.append(dest)
inferred_dict[dest] = x
for kw in declared_args:
# 1) make sure that this declared arg conforms to the function
# signature and therefore only refines an inferred arg:
#
# @arg('foo') maps to func(foo)
# @arg('--bar') maps to func(bar=...)
#
dest = _get_dest(parser, kw)
if dest in inferred_dict:
# 2) merge declared args into inferred ones (e.g. help=...)
inferred_dict[dest].update(**kw)
else:
varkw = getattr(spec, 'varkw', getattr(spec, 'keywords', []))
if varkw:
# function accepts **kwargs
dests.append(dest)
inferred_dict[dest] = kw
else:
xs = (inferred_dict[x]['option_strings'] for x in dests)
raise ValueError('{func}: argument {flags} does not fit '
'function signature: {sig}'.format(
flags=', '.join(kw['option_strings']),
func=function.__name__,
sig=', '.join('/'.join(x) for x in xs)))
# pack the modified data back into a list
inferred_args = [inferred_dict[x] for x in dests]
command_args = inferred_args or declared_args
# add types, actions, etc. (e.g. default=3 implies type=int)
command_args = [_guess(x) for x in command_args]
for draft in command_args:
draft = draft.copy()
dest_or_opt_strings = draft.pop('option_strings')
if parser.add_help and '-h' in dest_or_opt_strings:
dest_or_opt_strings = [x for x in dest_or_opt_strings if x != '-h']
completer = draft.pop('completer', None)
try:
action = parser.add_argument(*dest_or_opt_strings, **draft)
if COMPLETION_ENABLED and completer:
action.completer = completer
except Exception as e:
raise type(e)('{func}: cannot add arg {args}: {msg}'.format(
args='/'.join(dest_or_opt_strings), func=function.__name__, msg=e))
if function.__doc__ and not parser.description:
parser.description = function.__doc__
parser.set_defaults(function=function)
def set_default_command(parser, function):
""" Sets default command (i.e. a function) for given parser.
If `parser.description` is empty and the function has a docstring,
it is used as the description.
.. note::
An attempt to set default command to a parser which already has
subparsers (e.g. added with :func:`~argh.assembling.add_commands`)
results in a `RuntimeError`.
.. note::
If there are both explicitly declared arguments (e.g. via
:func:`~argh.decorators.arg`) and ones inferred from the function
signature (e.g. via :func:`~argh.decorators.command`), declared ones
will be merged into inferred ones. If an argument does not conform
function signature, `ValueError` is raised.
.. note::
If the parser was created with ``add_help=True`` (which is by default),
option name ``-h`` is silently removed from any argument.
"""
if parser._subparsers:
raise RuntimeError('Cannot set default command to a parser with '
'existing subparsers')
function = _fix_compat_issue29(function)
spec = compat.getargspec(function)
declared_args = getattr(function, ATTR_ARGS, [])
inferred_args = list(_get_args_from_signature(function))
if inferred_args and declared_args:
# We've got a mixture of declared and inferred arguments
# FIXME this is an ugly hack for preserving order
dests = []
inferred_dict = {}
for x in inferred_args:
dest = _get_dest(parser, x)
dests.append(dest)
inferred_dict[dest] = x
for kw in declared_args:
# 1) make sure that this declared arg conforms to the function
# signature and therefore only refines an inferred arg:
#
# @arg('foo') maps to func(foo)
# @arg('--bar') maps to func(bar=...)
#
dest = _get_dest(parser, kw)
if dest in inferred_dict:
# 2) merge declared args into inferred ones (e.g. help=...)
inferred_dict[dest].update(**kw)
else:
varkw = getattr(spec, 'varkw', getattr(spec, 'keywords', []))
if varkw:
# function accepts **kwargs
dests.append(dest)
inferred_dict[dest] = kw
else:
xs = (inferred_dict[x]['option_strings'] for x in dests)
raise ValueError('{func}: argument {flags} does not fit '
'function signature: {sig}'.format(
flags=', '.join(kw['option_strings']),
func=function.__name__,
sig=', '.join('/'.join(x)
for x in xs)))
# pack the modified data back into a list
inferred_args = [inferred_dict[x] for x in dests]
command_args = inferred_args or declared_args
# add types, actions, etc. (e.g. default=3 implies type=int)
command_args = [_guess(x) for x in command_args]
for draft in command_args:
draft = draft.copy()
dest_or_opt_strings = draft.pop('option_strings')
if parser.add_help and '-h' in dest_or_opt_strings:
dest_or_opt_strings = [x for x in dest_or_opt_strings if x != '-h']
completer = draft.pop('completer', None)
try:
action = parser.add_argument(*dest_or_opt_strings, **draft)
if COMPLETION_ENABLED and completer:
action.completer = completer
except Exception as e:
raise type(e)('{func}: cannot add arg {args}: {msg}'.format(
args='/'.join(dest_or_opt_strings),
func=function.__name__,
msg=e))
if function.__doc__ and not parser.description:
parser.description = function.__doc__
parser.set_defaults(function=function)