import errno
import inspect
import os
import sys
from contextlib import contextmanager
from functools import update_wrapper
from itertools import repeat
from ._compat import isidentifier
from ._compat import iteritems
from ._compat import PY2
from ._compat import string_types
from ._unicodefun import _check_for_unicode_literals
from ._unicodefun import _verify_python3_env
from .exceptions import Abort
from .exceptions import BadParameter
from .exceptions import ClickException
from .exceptions import Exit
from .exceptions import MissingParameter
from .exceptions import UsageError
from .formatting import HelpFormatter
from .formatting import join_options
from .globals import pop_context
from .globals import push_context
from .parser import OptionParser
from .parser import split_opt
from .termui import confirm
from .termui import prompt
from .termui import style
from .types import BOOL
from .types import convert_type
from .types import IntRange
from .utils import echo
from .utils import get_os_args
from .utils import make_default_short_help
from .utils import make_str
from .utils import PacifyFlushWrapper
_missing = object()
SUBCOMMAND_METAVAR = "COMMAND [ARGS]..."
SUBCOMMANDS_METAVAR = "COMMAND1 [ARGS]... [COMMAND2 [ARGS]...]..."
DEPRECATED_HELP_NOTICE = " (DEPRECATED)"
DEPRECATED_INVOKE_NOTICE = "DeprecationWarning: The command %(name)s is deprecated."
def _maybe_show_deprecated_notice(cmd):
if cmd.deprecated:
echo(style(DEPRECATED_INVOKE_NOTICE % {"name": cmd.name}, fg="red"), err=True)
def fast_exit(code):
"""Exit without garbage collection, this speeds up exit by about 10ms for
things like bash completion.
"""
sys.stdout.flush()
sys.stderr.flush()
os._exit(code)
def _bashcomplete(cmd, prog_name, complete_var=None):
"""Internal handler for the bash completion support."""
if complete_var is None:
complete_var = "_{}_COMPLETE".format(prog_name.replace("-", "_").upper())
complete_instr = os.environ.get(complete_var)
if not complete_instr:
return
from ._bashcomplete import bashcomplete
if bashcomplete(cmd, prog_name, complete_var, complete_instr):
fast_exit(1)
def _check_multicommand(base_command, cmd_name, cmd, register=False):
if not base_command.chain or not isinstance(cmd, MultiCommand):
return
if register:
hint = (
"It is not possible to add multi commands as children to"
" another multi command that is in chain mode."
)
else:
hint = (
"Found a multi command as subcommand to a multi command"
" that is in chain mode. This is not supported."
)
raise RuntimeError(
"{}. Command '{}' is set to chain and '{}' was added as"
" subcommand but it in itself is a multi command. ('{}' is a {}"
" within a chained {} named '{}').".format(
hint,
base_command.name,
cmd_name,
cmd_name,
cmd.__class__.__name__,
base_command.__class__.__name__,
base_command.name,
)
)
def batch(iterable, batch_size):
return list(zip(*repeat(iter(iterable), batch_size)))
def invoke_param_callback(callback, ctx, param, value):
code = getattr(callback, "__code__", None)
args = getattr(code, "co_argcount", 3)
if args < 3:
from warnings import warn
warn(
"Parameter callbacks take 3 args, (ctx, param, value). The"
" 2-arg style is deprecated and will be removed in 8.0.".format(callback),
DeprecationWarning,
stacklevel=3,
)
return callback(ctx, value)
return callback(ctx, param, value)
@contextmanager
def augment_usage_errors(ctx, param=None):
"""Context manager that attaches extra information to exceptions."""
try:
yield
except BadParameter as e:
if e.ctx is None:
e.ctx = ctx
if param is not None and e.param is None:
e.param = param
raise
except UsageError as e:
if e.ctx is None:
e.ctx = ctx
raise
def iter_params_for_processing(invocation_order, declaration_order):
"""Given a sequence of parameters in the order as should be considered
for processing and an iterable of parameters that exist, this returns
a list in the correct order as they should be processed.
"""
def sort_key(item):
try:
idx = invocation_order.index(item)
except ValueError:
idx = float("inf")
return (not item.is_eager, idx)
return sorted(declaration_order, key=sort_key)
[docs]class Context(object):
"""The context is a special internal object that holds state relevant
for the script execution at every single level. It's normally invisible
to commands unless they opt-in to getting access to it.
The context is useful as it can pass internal objects around and can
control special execution features such as reading data from
environment variables.
A context can be used as context manager in which case it will call
:meth:`close` on teardown.
.. versionadded:: 2.0
Added the `resilient_parsing`, `help_option_names`,
`token_normalize_func` parameters.
.. versionadded:: 3.0
Added the `allow_extra_args` and `allow_interspersed_args`
parameters.
.. versionadded:: 4.0
Added the `color`, `ignore_unknown_options`, and
`max_content_width` parameters.
.. versionadded:: 7.1
Added the `show_default` parameter.
:param command: the command class for this context.
:param parent: the parent context.
:param info_name: the info name for this invocation. Generally this
is the most descriptive name for the script or
command. For the toplevel script it is usually
the name of the script, for commands below it it's
the name of the script.
:param obj: an arbitrary object of user data.
:param auto_envvar_prefix: the prefix to use for automatic environment
variables. If this is `None` then reading
from environment variables is disabled. This
does not affect manually set environment
variables which are always read.
:param default_map: a dictionary (like object) with default values
for parameters.
:param terminal_width: the width of the terminal. The default is
inherit from parent context. If no context
defines the terminal width then auto
detection will be applied.
:param max_content_width: the maximum width for content rendered by
Click (this currently only affects help
pages). This defaults to 80 characters if
not overridden. In other words: even if the
terminal is larger than that, Click will not
format things wider than 80 characters by
default. In addition to that, formatters might
add some safety mapping on the right.
:param resilient_parsing: if this flag is enabled then Click will
parse without any interactivity or callback
invocation. Default values will also be
ignored. This is useful for implementing
things such as completion support.
:param allow_extra_args: if this is set to `True` then extra arguments
at the end will not raise an error and will be
kept on the context. The default is to inherit
from the command.
:param allow_interspersed_args: if this is set to `False` then options
and arguments cannot be mixed. The
default is to inherit from the command.
:param ignore_unknown_options: instructs click to ignore options it does
not know and keeps them for later
processing.
:param help_option_names: optionally a list of strings that define how
the default help parameter is named. The
default is ``['--help']``.
:param token_normalize_func: an optional function that is used to
normalize tokens (options, choices,
etc.). This for instance can be used to
implement case insensitive behavior.
:param color: controls if the terminal supports ANSI colors or not. The
default is autodetection. This is only needed if ANSI
codes are used in texts that Click prints which is by
default not the case. This for instance would affect
help output.
:param show_default: if True, shows defaults for all options.
Even if an option is later created with show_default=False,
this command-level setting overrides it.
"""
def __init__(
self,
command,
parent=None,
info_name=None,
obj=None,
auto_envvar_prefix=None,
default_map=None,
terminal_width=None,
max_content_width=None,
resilient_parsing=False,
allow_extra_args=None,
allow_interspersed_args=None,
ignore_unknown_options=None,
help_option_names=None,
token_normalize_func=None,
color=None,
show_default=None,
):
#: the parent context or `None` if none exists.
self.parent = parent
#: the :class:`Command` for this context.
self.command = command
#: the descriptive information name
self.info_name = info_name
#: the parsed parameters except if the value is hidden in which
#: case it's not remembered.
self.params = {}
#: the leftover arguments.
self.args = []
#: protected arguments. These are arguments that are prepended
#: to `args` when certain parsing scenarios are encountered but
#: must be never propagated to another arguments. This is used
#: to implement nested parsing.
self.protected_args = []
if obj is None and parent is not None:
obj = parent.obj
#: the user object stored.
self.obj = obj
self._meta = getattr(parent, "meta", {})
#: A dictionary (-like object) with defaults for parameters.
if (
default_map is None
and parent is not None
and parent.default_map is not None
):
default_map = parent.default_map.get(info_name)
self.default_map = default_map
#: This flag indicates if a subcommand is going to be executed. A
#: group callback can use this information to figure out if it's
#: being executed directly or because the execution flow passes
#: onwards to a subcommand. By default it's None, but it can be
#: the name of the subcommand to execute.
#:
#: If chaining is enabled this will be set to ``'*'`` in case
#: any commands are executed. It is however not possible to
#: figure out which ones. If you require this knowledge you
#: should use a :func:`resultcallback`.
self.invoked_subcommand = None
if terminal_width is None and parent is not None:
terminal_width = parent.terminal_width
#: The width of the terminal (None is autodetection).
self.terminal_width = terminal_width
if max_content_width is None and parent is not None:
max_content_width = parent.max_content_width
#: The maximum width of formatted content (None implies a sensible
#: default which is 80 for most things).
self.max_content_width = max_content_width
if allow_extra_args is None:
allow_extra_args = command.allow_extra_args
#: Indicates if the context allows extra args or if it should
#: fail on parsing.
#:
#: .. versionadded:: 3.0
self.allow_extra_args = allow_extra_args
if allow_interspersed_args is None:
allow_interspersed_args = command.allow_interspersed_args
#: Indicates if the context allows mixing of arguments and
#: options or not.
#:
#: .. versionadded:: 3.0
self.allow_interspersed_args = allow_interspersed_args
if ignore_unknown_options is None:
ignore_unknown_options = command.ignore_unknown_options
#: Instructs click to ignore options that a command does not
#: understand and will store it on the context for later
#: processing. This is primarily useful for situations where you
#: want to call into external programs. Generally this pattern is
#: strongly discouraged because it's not possibly to losslessly
#: forward all arguments.
#:
#: .. versionadded:: 4.0
self.ignore_unknown_options = ignore_unknown_options
if help_option_names is None:
if parent is not None:
help_option_names = parent.help_option_names
else:
help_option_names = ["--help"]
#: The names for the help options.
self.help_option_names = help_option_names
if token_normalize_func is None and parent is not None:
token_normalize_func = parent.token_normalize_func
#: An optional normalization function for tokens. This is
#: options, choices, commands etc.
self.token_normalize_func = token_normalize_func
#: Indicates if resilient parsing is enabled. In that case Click
#: will do its best to not cause any failures and default values
#: will be ignored. Useful for completion.
self.resilient_parsing = resilient_parsing
# If there is no envvar prefix yet, but the parent has one and
# the command on this level has a name, we can expand the envvar
# prefix automatically.
if auto_envvar_prefix is None:
if (
parent is not None
and parent.auto_envvar_prefix is not None
and self.info_name is not None
):
auto_envvar_prefix = "{}_{}".format(
parent.auto_envvar_prefix, self.info_name.upper()
)
else:
auto_envvar_prefix = auto_envvar_prefix.upper()
if auto_envvar_prefix is not None:
auto_envvar_prefix = auto_envvar_prefix.replace("-", "_")
self.auto_envvar_prefix = auto_envvar_prefix
if color is None and parent is not None:
color = parent.color
#: Controls if styling output is wanted or not.
self.color = color
self.show_default = show_default
self._close_callbacks = []
self._depth = 0
def __enter__(self):
self._depth += 1
push_context(self)
return self
def __exit__(self, exc_type, exc_value, tb):
self._depth -= 1
if self._depth == 0:
self.close()
pop_context()
[docs] @contextmanager
def scope(self, cleanup=True):
"""This helper method can be used with the context object to promote
it to the current thread local (see :func:`get_current_context`).
The default behavior of this is to invoke the cleanup functions which
can be disabled by setting `cleanup` to `False`. The cleanup
functions are typically used for things such as closing file handles.
If the cleanup is intended the context object can also be directly
used as a context manager.
Example usage::
with ctx.scope():
assert get_current_context() is ctx
This is equivalent::
with ctx:
assert get_current_context() is ctx
.. versionadded:: 5.0
:param cleanup: controls if the cleanup functions should be run or
not. The default is to run these functions. In
some situations the context only wants to be
temporarily pushed in which case this can be disabled.
Nested pushes automatically defer the cleanup.
"""
if not cleanup:
self._depth += 1
try:
with self as rv:
yield rv
finally:
if not cleanup:
self._depth -= 1
@property
def meta(self):
"""This is a dictionary which is shared with all the contexts
that are nested. It exists so that click utilities can store some
state here if they need to. It is however the responsibility of
that code to manage this dictionary well.
The keys are supposed to be unique dotted strings. For instance
module paths are a good choice for it. What is stored in there is
irrelevant for the operation of click. However what is important is
that code that places data here adheres to the general semantics of
the system.
Example usage::
LANG_KEY = f'{__name__}.lang'
def set_language(value):
ctx = get_current_context()
ctx.meta[LANG_KEY] = value
def get_language():
return get_current_context().meta.get(LANG_KEY, 'en_US')
.. versionadded:: 5.0
"""
return self._meta
[docs] def make_formatter(self):
"""Creates the formatter for the help and usage output."""
return HelpFormatter(
width=self.terminal_width, max_width=self.max_content_width
)
[docs] def call_on_close(self, f):
"""This decorator remembers a function as callback that should be
executed when the context tears down. This is most useful to bind
resource handling to the script execution. For instance, file objects
opened by the :class:`File` type will register their close callbacks
here.
:param f: the function to execute on teardown.
"""
self._close_callbacks.append(f)
return f
[docs] def close(self):
"""Invokes all close callbacks."""
for cb in self._close_callbacks:
cb()
self._close_callbacks = []
@property
def command_path(self):
"""The computed command path. This is used for the ``usage``
information on the help page. It's automatically created by
combining the info names of the chain of contexts to the root.
"""
rv = ""
if self.info_name is not None:
rv = self.info_name
if self.parent is not None:
rv = "{} {}".format(self.parent.command_path, rv)
return rv.lstrip()
[docs] def find_root(self):
"""Finds the outermost context."""
node = self
while node.parent is not None:
node = node.parent
return node
[docs] def find_object(self, object_type):
"""Finds the closest object of a given type."""
node = self
while node is not None:
if isinstance(node.obj, object_type):
return node.obj
node = node.parent
[docs] def ensure_object(self, object_type):
"""Like :meth:`find_object` but sets the innermost object to a
new instance of `object_type` if it does not exist.
"""
rv = self.find_object(object_type)
if rv is None:
self.obj = rv = object_type()
return rv
[docs] def lookup_default(self, name):
"""Looks up the default for a parameter name. This by default
looks into the :attr:`default_map` if available.
"""
if self.default_map is not None:
rv = self.default_map.get(name)
if callable(rv):
rv = rv()
return rv
[docs] def fail(self, message):
"""Aborts the execution of the program with a specific error
message.
:param message: the error message to fail with.
"""
raise UsageError(message, self)
[docs] def abort(self):
"""Aborts the script."""
raise Abort()
[docs] def exit(self, code=0):
"""Exits the application with a given exit code."""
raise Exit(code)
[docs] def get_usage(self):
"""Helper method to get formatted usage string for the current
context and command.
"""
return self.command.get_usage(self)
[docs] def get_help(self):
"""Helper method to get formatted help page for the current
context and command.
"""
return self.command.get_help(self)
[docs] def invoke(*args, **kwargs): # noqa: B902
"""Invokes a command callback in exactly the way it expects. There
are two ways to invoke this method:
1. the first argument can be a callback and all other arguments and
keyword arguments are forwarded directly to the function.
2. the first argument is a click command object. In that case all
arguments are forwarded as well but proper click parameters
(options and click arguments) must be keyword arguments and Click
will fill in defaults.
Note that before Click 3.2 keyword arguments were not properly filled
in against the intention of this code and no context was created. For
more information about this change and why it was done in a bugfix
release see :ref:`upgrade-to-3.2`.
"""
self, callback = args[:2]
ctx = self
# It's also possible to invoke another command which might or
# might not have a callback. In that case we also fill
# in defaults and make a new context for this command.
if isinstance(callback, Command):
other_cmd = callback
callback = other_cmd.callback
ctx = Context(other_cmd, info_name=other_cmd.name, parent=self)
if callback is None:
raise TypeError(
"The given command does not have a callback that can be invoked."
)
for param in other_cmd.params:
if param.name not in kwargs and param.expose_value:
kwargs[param.name] = param.get_default(ctx)
args = args[2:]
with augment_usage_errors(self):
with ctx:
return callback(*args, **kwargs)
[docs] def forward(*args, **kwargs): # noqa: B902
"""Similar to :meth:`invoke` but fills in default keyword
arguments from the current context if the other command expects
it. This cannot invoke callbacks directly, only other commands.
"""
self, cmd = args[:2]
# It's also possible to invoke another command which might or
# might not have a callback.
if not isinstance(cmd, Command):
raise TypeError("Callback is not a command.")
for param in self.params:
if param not in kwargs:
kwargs[param] = self.params[param]
return self.invoke(cmd, **kwargs)
[docs]class BaseCommand(object):
"""The base command implements the minimal API contract of commands.
Most code will never use this as it does not implement a lot of useful
functionality but it can act as the direct subclass of alternative
parsing methods that do not depend on the Click parser.
For instance, this can be used to bridge Click and other systems like
argparse or docopt.
Because base commands do not implement a lot of the API that other
parts of Click take for granted, they are not supported for all
operations. For instance, they cannot be used with the decorators
usually and they have no built-in callback system.
.. versionchanged:: 2.0
Added the `context_settings` parameter.
:param name: the name of the command to use unless a group overrides it.
:param context_settings: an optional dictionary with defaults that are
passed to the context object.
"""
#: the default for the :attr:`Context.allow_extra_args` flag.
allow_extra_args = False
#: the default for the :attr:`Context.allow_interspersed_args` flag.
allow_interspersed_args = True
#: the default for the :attr:`Context.ignore_unknown_options` flag.
ignore_unknown_options = False
def __init__(self, name, context_settings=None):
#: the name the command thinks it has. Upon registering a command
#: on a :class:`Group` the group will default the command name
#: with this information. You should instead use the
#: :class:`Context`\'s :attr:`~Context.info_name` attribute.
self.name = name
if context_settings is None:
context_settings = {}
#: an optional dictionary with defaults passed to the context.
self.context_settings = context_settings
def __repr__(self):
return "<{} {}>".format(self.__class__.__name__, self.name)
[docs] def get_usage(self, ctx):
raise NotImplementedError("Base commands cannot get usage")
[docs] def get_help(self, ctx):
raise NotImplementedError("Base commands cannot get help")
[docs] def make_context(self, info_name, args, parent=None, **extra):
"""This function when given an info name and arguments will kick
off the parsing and create a new :class:`Context`. It does not
invoke the actual command callback though.
:param info_name: the info name for this invokation. Generally this
is the most descriptive name for the script or
command. For the toplevel script it's usually
the name of the script, for commands below it it's
the name of the script.
:param args: the arguments to parse as list of strings.
:param parent: the parent context if available.
:param extra: extra keyword arguments forwarded to the context
constructor.
"""
for key, value in iteritems(self.context_settings):
if key not in extra:
extra[key] = value
ctx = Context(self, info_name=info_name, parent=parent, **extra)
with ctx.scope(cleanup=False):
self.parse_args(ctx, args)
return ctx
[docs] def parse_args(self, ctx, args):
"""Given a context and a list of arguments this creates the parser
and parses the arguments, then modifies the context as necessary.
This is automatically invoked by :meth:`make_context`.
"""
raise NotImplementedError("Base commands do not know how to parse arguments.")
[docs] def invoke(self, ctx):
"""Given a context, this invokes the command. The default
implementation is raising a not implemented error.
"""
raise NotImplementedError("Base commands are not invokable by default")
[docs] def main(
self,
args=None,
prog_name=None,
complete_var=None,
standalone_mode=True,
**extra
):
"""This is the way to invoke a script with all the bells and
whistles as a command line application. This will always terminate
the application after a call. If this is not wanted, ``SystemExit``
needs to be caught.
This method is also available by directly calling the instance of
a :class:`Command`.
.. versionadded:: 3.0
Added the `standalone_mode` flag to control the standalone mode.
:param args: the arguments that should be used for parsing. If not
provided, ``sys.argv[1:]`` is used.
:param prog_name: the program name that should be used. By default
the program name is constructed by taking the file
name from ``sys.argv[0]``.
:param complete_var: the environment variable that controls the
bash completion support. The default is
``"_<prog_name>_COMPLETE"`` with prog_name in
uppercase.
:param standalone_mode: the default behavior is to invoke the script
in standalone mode. Click will then
handle exceptions and convert them into
error messages and the function will never
return but shut down the interpreter. If
this is set to `False` they will be
propagated to the caller and the return
value of this function is the return value
of :meth:`invoke`.
:param extra: extra keyword arguments are forwarded to the context
constructor. See :class:`Context` for more information.
"""
# If we are in Python 3, we will verify that the environment is
# sane at this point or reject further execution to avoid a
# broken script.
if not PY2:
_verify_python3_env()
else:
_check_for_unicode_literals()
if args is None:
args = get_os_args()
else:
args = list(args)
if prog_name is None:
prog_name = make_str(
os.path.basename(sys.argv[0] if sys.argv else __file__)
)
# Hook for the Bash completion. This only activates if the Bash
# completion is actually enabled, otherwise this is quite a fast
# noop.
_bashcomplete(self, prog_name, complete_var)
try:
try:
with self.make_context(prog_name, args, **extra) as ctx:
rv = self.invoke(ctx)
if not standalone_mode:
return rv
# it's not safe to `ctx.exit(rv)` here!
# note that `rv` may actually contain data like "1" which
# has obvious effects
# more subtle case: `rv=[None, None]` can come out of
# chained commands which all returned `None` -- so it's not
# even always obvious that `rv` indicates success/failure
# by its truthiness/falsiness
ctx.exit()
except (EOFError, KeyboardInterrupt):
echo(file=sys.stderr)
raise Abort()
except ClickException as e:
if not standalone_mode:
raise
e.show()
sys.exit(e.exit_code)
except IOError as e:
if e.errno == errno.EPIPE:
sys.stdout = PacifyFlushWrapper(sys.stdout)
sys.stderr = PacifyFlushWrapper(sys.stderr)
sys.exit(1)
else:
raise
except Exit as e:
if standalone_mode:
sys.exit(e.exit_code)
else:
# in non-standalone mode, return the exit code
# note that this is only reached if `self.invoke` above raises
# an Exit explicitly -- thus bypassing the check there which
# would return its result
# the results of non-standalone execution may therefore be
# somewhat ambiguous: if there are codepaths which lead to
# `ctx.exit(1)` and to `return 1`, the caller won't be able to
# tell the difference between the two
return e.exit_code
except Abort:
if not standalone_mode:
raise
echo("Aborted!", file=sys.stderr)
sys.exit(1)
def __call__(self, *args, **kwargs):
"""Alias for :meth:`main`."""
return self.main(*args, **kwargs)
[docs]class Command(BaseCommand):
"""Commands are the basic building block of command line interfaces in
Click. A basic command handles command line parsing and might dispatch
more parsing to commands nested below it.
.. versionchanged:: 2.0
Added the `context_settings` parameter.
.. versionchanged:: 7.1
Added the `no_args_is_help` parameter.
:param name: the name of the command to use unless a group overrides it.
:param context_settings: an optional dictionary with defaults that are
passed to the context object.
:param callback: the callback to invoke. This is optional.
:param params: the parameters to register with this command. This can
be either :class:`Option` or :class:`Argument` objects.
:param help: the help string to use for this command.
:param epilog: like the help string but it's printed at the end of the
help page after everything else.
:param short_help: the short help to use for this command. This is
shown on the command listing of the parent command.
:param add_help_option: by default each command registers a ``--help``
option. This can be disabled by this parameter.
:param no_args_is_help: this controls what happens if no arguments are
provided. This option is disabled by default.
If enabled this will add ``--help`` as argument
if no arguments are passed
:param hidden: hide this command from help outputs.
:param deprecated: issues a message indicating that
the command is deprecated.
"""
def __init__(
self,
name,
context_settings=None,
callback=None,
params=None,
help=None,
epilog=None,
short_help=None,
options_metavar="[OPTIONS]",
add_help_option=True,
no_args_is_help=False,
hidden=False,
deprecated=False,
):
BaseCommand.__init__(self, name, context_settings)
#: the callback to execute when the command fires. This might be
#: `None` in which case nothing happens.
self.callback = callback
#: the list of parameters for this command in the order they
#: should show up in the help page and execute. Eager parameters
#: will automatically be handled before non eager ones.
self.params = params or []
# if a form feed (page break) is found in the help text, truncate help
# text to the content preceding the first form feed
if help and "\f" in help:
help = help.split("\f", 1)[0]
self.help = help
self.epilog = epilog
self.options_metavar = options_metavar
self.short_help = short_help
self.add_help_option = add_help_option
self.no_args_is_help = no_args_is_help
self.hidden = hidden
self.deprecated = deprecated
[docs] def get_usage(self, ctx):
"""Formats the usage line into a string and returns it.
Calls :meth:`format_usage` internally.
"""
formatter = ctx.make_formatter()
self.format_usage(ctx, formatter)
return formatter.getvalue().rstrip("\n")
[docs] def get_params(self, ctx):
rv = self.params
help_option = self.get_help_option(ctx)
if help_option is not None:
rv = rv + [help_option]
return rv
[docs] def collect_usage_pieces(self, ctx):
"""Returns all the pieces that go into the usage line and returns
it as a list of strings.
"""
rv = [self.options_metavar]
for param in self.get_params(ctx):
rv.extend(param.get_usage_pieces(ctx))
return rv
[docs] def get_help_option_names(self, ctx):
"""Returns the names for the help option."""
all_names = set(ctx.help_option_names)
for param in self.params:
all_names.difference_update(param.opts)
all_names.difference_update(param.secondary_opts)
return all_names
[docs] def get_help_option(self, ctx):
"""Returns the help option object."""
help_options = self.get_help_option_names(ctx)
if not help_options or not self.add_help_option:
return
def show_help(ctx, param, value):
if value and not ctx.resilient_parsing:
echo(ctx.get_help(), color=ctx.color)
ctx.exit()
return Option(
help_options,
is_flag=True,
is_eager=True,
expose_value=False,
callback=show_help,
help="Show this message and exit.",
)
[docs] def make_parser(self, ctx):
"""Creates the underlying option parser for this command."""
parser = OptionParser(ctx)
for param in self.get_params(ctx):
param.add_to_parser(parser, ctx)
return parser
[docs] def get_help(self, ctx):
"""Formats the help into a string and returns it.
Calls :meth:`format_help` internally.
"""
formatter = ctx.make_formatter()
self.format_help(ctx, formatter)
return formatter.getvalue().rstrip("\n")
[docs] def get_short_help_str(self, limit=45):
"""Gets short help for the command or makes it by shortening the
long help string.
"""
return (
self.short_help
or self.help
and make_default_short_help(self.help, limit)
or ""
)
[docs] def format_help_text(self, ctx, formatter):
"""Writes the help text to the formatter if it exists."""
if self.help:
formatter.write_paragraph()
with formatter.indentation():
help_text = self.help
if self.deprecated:
help_text += DEPRECATED_HELP_NOTICE
formatter.write_text(help_text)
elif self.deprecated:
formatter.write_paragraph()
with formatter.indentation():
formatter.write_text(DEPRECATED_HELP_NOTICE)
[docs] def parse_args(self, ctx, args):
if not args and self.no_args_is_help and not ctx.resilient_parsing:
echo(ctx.get_help(), color=ctx.color)
ctx.exit()
parser = self.make_parser(ctx)
opts, args, param_order = parser.parse_args(args=args)
for param in iter_params_for_processing(param_order, self.get_params(ctx)):
value, args = param.handle_parse_result(ctx, opts, args)
if args and not ctx.allow_extra_args and not ctx.resilient_parsing:
ctx.fail(
"Got unexpected extra argument{} ({})".format(
"s" if len(args) != 1 else "", " ".join(map(make_str, args))
)
)
ctx.args = args
return args
[docs] def invoke(self, ctx):
"""Given a context, this invokes the attached callback (if it exists)
in the right way.
"""
_maybe_show_deprecated_notice(self)
if self.callback is not None:
return ctx.invoke(self.callback, **ctx.params)
[docs]class MultiCommand(Command):
"""A multi command is the basic implementation of a command that
dispatches to subcommands. The most common version is the
:class:`Group`.
:param invoke_without_command: this controls how the multi command itself
is invoked. By default it's only invoked
if a subcommand is provided.
:param no_args_is_help: this controls what happens if no arguments are
provided. This option is enabled by default if
`invoke_without_command` is disabled or disabled
if it's enabled. If enabled this will add
``--help`` as argument if no arguments are
passed.
:param subcommand_metavar: the string that is used in the documentation
to indicate the subcommand place.
:param chain: if this is set to `True` chaining of multiple subcommands
is enabled. This restricts the form of commands in that
they cannot have optional arguments but it allows
multiple commands to be chained together.
:param result_callback: the result callback to attach to this multi
command.
"""
allow_extra_args = True
allow_interspersed_args = False
def __init__(
self,
name=None,
invoke_without_command=False,
no_args_is_help=None,
subcommand_metavar=None,
chain=False,
result_callback=None,
**attrs
):
Command.__init__(self, name, **attrs)
if no_args_is_help is None:
no_args_is_help = not invoke_without_command
self.no_args_is_help = no_args_is_help
self.invoke_without_command = invoke_without_command
if subcommand_metavar is None:
if chain:
subcommand_metavar = SUBCOMMANDS_METAVAR
else:
subcommand_metavar = SUBCOMMAND_METAVAR
self.subcommand_metavar = subcommand_metavar
self.chain = chain
#: The result callback that is stored. This can be set or
#: overridden with the :func:`resultcallback` decorator.
self.result_callback = result_callback
if self.chain:
for param in self.params:
if isinstance(param, Argument) and not param.required:
raise RuntimeError(
"Multi commands in chain mode cannot have"
" optional arguments."
)
[docs] def collect_usage_pieces(self, ctx):
rv = Command.collect_usage_pieces(self, ctx)
rv.append(self.subcommand_metavar)
return rv
[docs] def resultcallback(self, replace=False):
"""Adds a result callback to the chain command. By default if a
result callback is already registered this will chain them but
this can be disabled with the `replace` parameter. The result
callback is invoked with the return value of the subcommand
(or the list of return values from all subcommands if chaining
is enabled) as well as the parameters as they would be passed
to the main callback.
Example::
@click.group()
@click.option('-i', '--input', default=23)
def cli(input):
return 42
@cli.resultcallback()
def process_result(result, input):
return result + input
.. versionadded:: 3.0
:param replace: if set to `True` an already existing result
callback will be removed.
"""
def decorator(f):
old_callback = self.result_callback
if old_callback is None or replace:
self.result_callback = f
return f
def function(__value, *args, **kwargs):
return f(old_callback(__value, *args, **kwargs), *args, **kwargs)
self.result_callback = rv = update_wrapper(function, f)
return rv
return decorator
[docs] def parse_args(self, ctx, args):
if not args and self.no_args_is_help and not ctx.resilient_parsing:
echo(ctx.get_help(), color=ctx.color)
ctx.exit()
rest = Command.parse_args(self, ctx, args)
if self.chain:
ctx.protected_args = rest
ctx.args = []
elif rest:
ctx.protected_args, ctx.args = rest[:1], rest[1:]
return ctx.args
[docs] def invoke(self, ctx):
def _process_result(value):
if self.result_callback is not None:
value = ctx.invoke(self.result_callback, value, **ctx.params)
return value
if not ctx.protected_args:
# If we are invoked without command the chain flag controls
# how this happens. If we are not in chain mode, the return
# value here is the return value of the command.
# If however we are in chain mode, the return value is the
# return value of the result processor invoked with an empty
# list (which means that no subcommand actually was executed).
if self.invoke_without_command:
if not self.chain:
return Command.invoke(self, ctx)
with ctx:
Command.invoke(self, ctx)
return _process_result([])
ctx.fail("Missing command.")
# Fetch args back out
args = ctx.protected_args + ctx.args
ctx.args = []
ctx.protected_args = []
# If we're not in chain mode, we only allow the invocation of a
# single command but we also inform the current context about the
# name of the command to invoke.
if not self.chain:
# Make sure the context is entered so we do not clean up
# resources until the result processor has worked.
with ctx:
cmd_name, cmd, args = self.resolve_command(ctx, args)
ctx.invoked_subcommand = cmd_name
Command.invoke(self, ctx)
sub_ctx = cmd.make_context(cmd_name, args, parent=ctx)
with sub_ctx:
return _process_result(sub_ctx.command.invoke(sub_ctx))
# In chain mode we create the contexts step by step, but after the
# base command has been invoked. Because at that point we do not
# know the subcommands yet, the invoked subcommand attribute is
# set to ``*`` to inform the command that subcommands are executed
# but nothing else.
with ctx:
ctx.invoked_subcommand = "*" if args else None
Command.invoke(self, ctx)
# Otherwise we make every single context and invoke them in a
# chain. In that case the return value to the result processor
# is the list of all invoked subcommand's results.
contexts = []
while args:
cmd_name, cmd, args = self.resolve_command(ctx, args)
sub_ctx = cmd.make_context(
cmd_name,
args,
parent=ctx,
allow_extra_args=True,
allow_interspersed_args=False,
)
contexts.append(sub_ctx)
args, sub_ctx.args = sub_ctx.args, []
rv = []
for sub_ctx in contexts:
with sub_ctx:
rv.append(sub_ctx.command.invoke(sub_ctx))
return _process_result(rv)
[docs] def resolve_command(self, ctx, args):
cmd_name = make_str(args[0])
original_cmd_name = cmd_name
# Get the command
cmd = self.get_command(ctx, cmd_name)
# If we can't find the command but there is a normalization
# function available, we try with that one.
if cmd is None and ctx.token_normalize_func is not None:
cmd_name = ctx.token_normalize_func(cmd_name)
cmd = self.get_command(ctx, cmd_name)
# If we don't find the command we want to show an error message
# to the user that it was not provided. However, there is
# something else we should do: if the first argument looks like
# an option we want to kick off parsing again for arguments to
# resolve things like --help which now should go to the main
# place.
if cmd is None and not ctx.resilient_parsing:
if split_opt(cmd_name)[0]:
self.parse_args(ctx, ctx.args)
ctx.fail("No such command '{}'.".format(original_cmd_name))
return cmd_name, cmd, args[1:]
[docs] def get_command(self, ctx, cmd_name):
"""Given a context and a command name, this returns a
:class:`Command` object if it exists or returns `None`.
"""
raise NotImplementedError()
[docs] def list_commands(self, ctx):
"""Returns a list of subcommand names in the order they should
appear.
"""
return []
[docs]class Group(MultiCommand):
"""A group allows a command to have subcommands attached. This is the
most common way to implement nesting in Click.
:param commands: a dictionary of commands.
"""
def __init__(self, name=None, commands=None, **attrs):
MultiCommand.__init__(self, name, **attrs)
#: the registered subcommands by their exported names.
self.commands = commands or {}
[docs] def add_command(self, cmd, name=None):
"""Registers another :class:`Command` with this group. If the name
is not provided, the name of the command is used.
"""
name = name or cmd.name
if name is None:
raise TypeError("Command has no name.")
_check_multicommand(self, name, cmd, register=True)
self.commands[name] = cmd
[docs] def command(self, *args, **kwargs):
"""A shortcut decorator for declaring and attaching a command to
the group. This takes the same arguments as :func:`command` but
immediately registers the created command with this instance by
calling into :meth:`add_command`.
"""
from .decorators import command
def decorator(f):
cmd = command(*args, **kwargs)(f)
self.add_command(cmd)
return cmd
return decorator
[docs] def group(self, *args, **kwargs):
"""A shortcut decorator for declaring and attaching a group to
the group. This takes the same arguments as :func:`group` but
immediately registers the created command with this instance by
calling into :meth:`add_command`.
"""
from .decorators import group
def decorator(f):
cmd = group(*args, **kwargs)(f)
self.add_command(cmd)
return cmd
return decorator
[docs] def get_command(self, ctx, cmd_name):
return self.commands.get(cmd_name)
[docs] def list_commands(self, ctx):
return sorted(self.commands)
[docs]class CommandCollection(MultiCommand):
"""A command collection is a multi command that merges multiple multi
commands together into one. This is a straightforward implementation
that accepts a list of different multi commands as sources and
provides all the commands for each of them.
"""
def __init__(self, name=None, sources=None, **attrs):
MultiCommand.__init__(self, name, **attrs)
#: The list of registered multi commands.
self.sources = sources or []
[docs] def add_source(self, multi_cmd):
"""Adds a new multi command to the chain dispatcher."""
self.sources.append(multi_cmd)
[docs] def get_command(self, ctx, cmd_name):
for source in self.sources:
rv = source.get_command(ctx, cmd_name)
if rv is not None:
if self.chain:
_check_multicommand(self, cmd_name, rv)
return rv
[docs] def list_commands(self, ctx):
rv = set()
for source in self.sources:
rv.update(source.list_commands(ctx))
return sorted(rv)
[docs]class Parameter(object):
r"""A parameter to a command comes in two versions: they are either
:class:`Option`\s or :class:`Argument`\s. Other subclasses are currently
not supported by design as some of the internals for parsing are
intentionally not finalized.
Some settings are supported by both options and arguments.
:param param_decls: the parameter declarations for this option or
argument. This is a list of flags or argument
names.
:param type: the type that should be used. Either a :class:`ParamType`
or a Python type. The later is converted into the former
automatically if supported.
:param required: controls if this is optional or not.
:param default: the default value if omitted. This can also be a callable,
in which case it's invoked when the default is needed
without any arguments.
:param callback: a callback that should be executed after the parameter
was matched. This is called as ``fn(ctx, param,
value)`` and needs to return the value.
:param nargs: the number of arguments to match. If not ``1`` the return
value is a tuple instead of single value. The default for
nargs is ``1`` (except if the type is a tuple, then it's
the arity of the tuple).
:param metavar: how the value is represented in the help page.
:param expose_value: if this is `True` then the value is passed onwards
to the command callback and stored on the context,
otherwise it's skipped.
:param is_eager: eager values are processed before non eager ones. This
should not be set for arguments or it will inverse the
order of processing.
:param envvar: a string or list of strings that are environment variables
that should be checked.
.. versionchanged:: 7.1
Empty environment variables are ignored rather than taking the
empty string value. This makes it possible for scripts to clear
variables if they can't unset them.
.. versionchanged:: 2.0
Changed signature for parameter callback to also be passed the
parameter. The old callback format will still work, but it will
raise a warning to give you a chance to migrate the code easier.
"""
param_type_name = "parameter"
def __init__(
self,
param_decls=None,
type=None,
required=False,
default=None,
callback=None,
nargs=None,
metavar=None,
expose_value=True,
is_eager=False,
envvar=None,
autocompletion=None,
):
self.name, self.opts, self.secondary_opts = self._parse_decls(
param_decls or (), expose_value
)
self.type = convert_type(type, default)
# Default nargs to what the type tells us if we have that
# information available.
if nargs is None:
if self.type.is_composite:
nargs = self.type.arity
else:
nargs = 1
self.required = required
self.callback = callback
self.nargs = nargs
self.multiple = False
self.expose_value = expose_value
self.default = default
self.is_eager = is_eager
self.metavar = metavar
self.envvar = envvar
self.autocompletion = autocompletion
def __repr__(self):
return "<{} {}>".format(self.__class__.__name__, self.name)
@property
def human_readable_name(self):
"""Returns the human readable name of this parameter. This is the
same as the name for options, but the metavar for arguments.
"""
return self.name
[docs] def get_default(self, ctx):
"""Given a context variable this calculates the default value."""
# Otherwise go with the regular default.
if callable(self.default):
rv = self.default()
else:
rv = self.default
return self.type_cast_value(ctx, rv)
[docs] def add_to_parser(self, parser, ctx):
pass
[docs] def consume_value(self, ctx, opts):
value = opts.get(self.name)
if value is None:
value = self.value_from_envvar(ctx)
if value is None:
value = ctx.lookup_default(self.name)
return value
[docs] def type_cast_value(self, ctx, value):
"""Given a value this runs it properly through the type system.
This automatically handles things like `nargs` and `multiple` as
well as composite types.
"""
if self.type.is_composite:
if self.nargs <= 1:
raise TypeError(
"Attempted to invoke composite type but nargs has"
" been set to {}. This is not supported; nargs"
" needs to be set to a fixed value > 1.".format(self.nargs)
)
if self.multiple:
return tuple(self.type(x or (), self, ctx) for x in value or ())
return self.type(value or (), self, ctx)
def _convert(value, level):
if level == 0:
return self.type(value, self, ctx)
return tuple(_convert(x, level - 1) for x in value or ())
return _convert(value, (self.nargs != 1) + bool(self.multiple))
[docs] def process_value(self, ctx, value):
"""Given a value and context this runs the logic to convert the
value as necessary.
"""
# If the value we were given is None we do nothing. This way
# code that calls this can easily figure out if something was
# not provided. Otherwise it would be converted into an empty
# tuple for multiple invocations which is inconvenient.
if value is not None:
return self.type_cast_value(ctx, value)
[docs] def value_is_missing(self, value):
if value is None:
return True
if (self.nargs != 1 or self.multiple) and value == ():
return True
return False
[docs] def full_process_value(self, ctx, value):
value = self.process_value(ctx, value)
if value is None and not ctx.resilient_parsing:
value = self.get_default(ctx)
if self.required and self.value_is_missing(value):
raise MissingParameter(ctx=ctx, param=self)
return value
[docs] def resolve_envvar_value(self, ctx):
if self.envvar is None:
return
if isinstance(self.envvar, (tuple, list)):
for envvar in self.envvar:
rv = os.environ.get(envvar)
if rv is not None:
return rv
else:
rv = os.environ.get(self.envvar)
if rv != "":
return rv
[docs] def value_from_envvar(self, ctx):
rv = self.resolve_envvar_value(ctx)
if rv is not None and self.nargs != 1:
rv = self.type.split_envvar_value(rv)
return rv
[docs] def handle_parse_result(self, ctx, opts, args):
with augment_usage_errors(ctx, param=self):
value = self.consume_value(ctx, opts)
try:
value = self.full_process_value(ctx, value)
except Exception:
if not ctx.resilient_parsing:
raise
value = None
if self.callback is not None:
try:
value = invoke_param_callback(self.callback, ctx, self, value)
except Exception:
if not ctx.resilient_parsing:
raise
if self.expose_value:
ctx.params[self.name] = value
return value, args
[docs] def get_help_record(self, ctx):
pass
[docs] def get_usage_pieces(self, ctx):
return []
[docs] def get_error_hint(self, ctx):
"""Get a stringified version of the param for use in error messages to
indicate which param caused the error.
"""
hint_list = self.opts or [self.human_readable_name]
return " / ".join(repr(x) for x in hint_list)
[docs]class Option(Parameter):
"""Options are usually optional values on the command line and
have some extra features that arguments don't have.
All other parameters are passed onwards to the parameter constructor.
:param show_default: controls if the default value should be shown on the
help page. Normally, defaults are not shown. If this
value is a string, it shows the string instead of the
value. This is particularly useful for dynamic options.
:param show_envvar: controls if an environment variable should be shown on
the help page. Normally, environment variables
are not shown.
:param prompt: if set to `True` or a non empty string then the user will be
prompted for input. If set to `True` the prompt will be the
option name capitalized.
:param confirmation_prompt: if set then the value will need to be confirmed
if it was prompted for.
:param hide_input: if this is `True` then the input on the prompt will be
hidden from the user. This is useful for password
input.
:param is_flag: forces this option to act as a flag. The default is
auto detection.
:param flag_value: which value should be used for this flag if it's
enabled. This is set to a boolean automatically if
the option string contains a slash to mark two options.
:param multiple: if this is set to `True` then the argument is accepted
multiple times and recorded. This is similar to ``nargs``
in how it works but supports arbitrary number of
arguments.
:param count: this flag makes an option increment an integer.
:param allow_from_autoenv: if this is enabled then the value of this
parameter will be pulled from an environment
variable in case a prefix is defined on the
context.
:param help: the help string.
:param hidden: hide this option from help outputs.
"""
param_type_name = "option"
def __init__(
self,
param_decls=None,
show_default=False,
prompt=False,
confirmation_prompt=False,
hide_input=False,
is_flag=None,
flag_value=None,
multiple=False,
count=False,
allow_from_autoenv=True,
type=None,
help=None,
hidden=False,
show_choices=True,
show_envvar=False,
**attrs
):
default_is_missing = attrs.get("default", _missing) is _missing
Parameter.__init__(self, param_decls, type=type, **attrs)
if prompt is True:
prompt_text = self.name.replace("_", " ").capitalize()
elif prompt is False:
prompt_text = None
else:
prompt_text = prompt
self.prompt = prompt_text
self.confirmation_prompt = confirmation_prompt
self.hide_input = hide_input
self.hidden = hidden
# Flags
if is_flag is None:
if flag_value is not None:
is_flag = True
else:
is_flag = bool(self.secondary_opts)
if is_flag and default_is_missing:
self.default = False
if flag_value is None:
flag_value = not self.default
self.is_flag = is_flag
self.flag_value = flag_value
if self.is_flag and isinstance(self.flag_value, bool) and type in [None, bool]:
self.type = BOOL
self.is_bool_flag = True
else:
self.is_bool_flag = False
# Counting
self.count = count
if count:
if type is None:
self.type = IntRange(min=0)
if default_is_missing:
self.default = 0
self.multiple = multiple
self.allow_from_autoenv = allow_from_autoenv
self.help = help
self.show_default = show_default
self.show_choices = show_choices
self.show_envvar = show_envvar
# Sanity check for stuff we don't support
if __debug__:
if self.nargs < 0:
raise TypeError("Options cannot have nargs < 0")
if self.prompt and self.is_flag and not self.is_bool_flag:
raise TypeError("Cannot prompt for flags that are not bools.")
if not self.is_bool_flag and self.secondary_opts:
raise TypeError("Got secondary option for non boolean flag.")
if self.is_bool_flag and self.hide_input and self.prompt is not None:
raise TypeError("Hidden input does not work with boolean flag prompts.")
if self.count:
if self.multiple:
raise TypeError(
"Options cannot be multiple and count at the same time."
)
elif self.is_flag:
raise TypeError(
"Options cannot be count and flags at the same time."
)
def _parse_decls(self, decls, expose_value):
opts = []
secondary_opts = []
name = None
possible_names = []
for decl in decls:
if isidentifier(decl):
if name is not None:
raise TypeError("Name defined twice")
name = decl
else:
split_char = ";" if decl[:1] == "/" else "/"
if split_char in decl:
first, second = decl.split(split_char, 1)
first = first.rstrip()
if first:
possible_names.append(split_opt(first))
opts.append(first)
second = second.lstrip()
if second:
secondary_opts.append(second.lstrip())
else:
possible_names.append(split_opt(decl))
opts.append(decl)
if name is None and possible_names:
possible_names.sort(key=lambda x: -len(x[0])) # group long options first
name = possible_names[0][1].replace("-", "_").lower()
if not isidentifier(name):
name = None
if name is None:
if not expose_value:
return None, opts, secondary_opts
raise TypeError("Could not determine name for option")
if not opts and not secondary_opts:
raise TypeError(
"No options defined but a name was passed ({}). Did you"
" mean to declare an argument instead of an option?".format(name)
)
return name, opts, secondary_opts
[docs] def add_to_parser(self, parser, ctx):
kwargs = {
"dest": self.name,
"nargs": self.nargs,
"obj": self,
}
if self.multiple:
action = "append"
elif self.count:
action = "count"
else:
action = "store"
if self.is_flag:
kwargs.pop("nargs", None)
action_const = "{}_const".format(action)
if self.is_bool_flag and self.secondary_opts:
parser.add_option(self.opts, action=action_const, const=True, **kwargs)
parser.add_option(
self.secondary_opts, action=action_const, const=False, **kwargs
)
else:
parser.add_option(
self.opts, action=action_const, const=self.flag_value, **kwargs
)
else:
kwargs["action"] = action
parser.add_option(self.opts, **kwargs)
[docs] def get_help_record(self, ctx):
if self.hidden:
return
any_prefix_is_slash = []
def _write_opts(opts):
rv, any_slashes = join_options(opts)
if any_slashes:
any_prefix_is_slash[:] = [True]
if not self.is_flag and not self.count:
rv += " {}".format(self.make_metavar())
return rv
rv = [_write_opts(self.opts)]
if self.secondary_opts:
rv.append(_write_opts(self.secondary_opts))
help = self.help or ""
extra = []
if self.show_envvar:
envvar = self.envvar
if envvar is None:
if self.allow_from_autoenv and ctx.auto_envvar_prefix is not None:
envvar = "{}_{}".format(ctx.auto_envvar_prefix, self.name.upper())
if envvar is not None:
extra.append(
"env var: {}".format(
", ".join(str(d) for d in envvar)
if isinstance(envvar, (list, tuple))
else envvar
)
)
if self.default is not None and (self.show_default or ctx.show_default):
if isinstance(self.show_default, string_types):
default_string = "({})".format(self.show_default)
elif isinstance(self.default, (list, tuple)):
default_string = ", ".join(str(d) for d in self.default)
elif inspect.isfunction(self.default):
default_string = "(dynamic)"
else:
default_string = self.default
extra.append("default: {}".format(default_string))
if self.required:
extra.append("required")
if extra:
help = "{}[{}]".format(
"{} ".format(help) if help else "", "; ".join(extra)
)
return ("; " if any_prefix_is_slash else " / ").join(rv), help
[docs] def get_default(self, ctx):
# If we're a non boolean flag our default is more complex because
# we need to look at all flags in the same group to figure out
# if we're the the default one in which case we return the flag
# value as default.
if self.is_flag and not self.is_bool_flag:
for param in ctx.command.params:
if param.name == self.name and param.default:
return param.flag_value
return None
return Parameter.get_default(self, ctx)
[docs] def prompt_for_value(self, ctx):
"""This is an alternative flow that can be activated in the full
value processing if a value does not exist. It will prompt the
user until a valid value exists and then returns the processed
value as result.
"""
# Calculate the default before prompting anything to be stable.
default = self.get_default(ctx)
# If this is a prompt for a flag we need to handle this
# differently.
if self.is_bool_flag:
return confirm(self.prompt, default)
return prompt(
self.prompt,
default=default,
type=self.type,
hide_input=self.hide_input,
show_choices=self.show_choices,
confirmation_prompt=self.confirmation_prompt,
value_proc=lambda x: self.process_value(ctx, x),
)
[docs] def resolve_envvar_value(self, ctx):
rv = Parameter.resolve_envvar_value(self, ctx)
if rv is not None:
return rv
if self.allow_from_autoenv and ctx.auto_envvar_prefix is not None:
envvar = "{}_{}".format(ctx.auto_envvar_prefix, self.name.upper())
return os.environ.get(envvar)
[docs] def value_from_envvar(self, ctx):
rv = self.resolve_envvar_value(ctx)
if rv is None:
return None
value_depth = (self.nargs != 1) + bool(self.multiple)
if value_depth > 0 and rv is not None:
rv = self.type.split_envvar_value(rv)
if self.multiple and self.nargs != 1:
rv = batch(rv, self.nargs)
return rv
[docs] def full_process_value(self, ctx, value):
if value is None and self.prompt is not None and not ctx.resilient_parsing:
return self.prompt_for_value(ctx)
return Parameter.full_process_value(self, ctx, value)
[docs]class Argument(Parameter):
"""Arguments are positional parameters to a command. They generally
provide fewer features than options but can have infinite ``nargs``
and are required by default.
All parameters are passed onwards to the parameter constructor.
"""
param_type_name = "argument"
def __init__(self, param_decls, required=None, **attrs):
if required is None:
if attrs.get("default") is not None:
required = False
else:
required = attrs.get("nargs", 1) > 0
Parameter.__init__(self, param_decls, required=required, **attrs)
if self.default is not None and self.nargs < 0:
raise TypeError(
"nargs=-1 in combination with a default value is not supported."
)
@property
def human_readable_name(self):
if self.metavar is not None:
return self.metavar
return self.name.upper()
def _parse_decls(self, decls, expose_value):
if not decls:
if not expose_value:
return None, [], []
raise TypeError("Could not determine name for argument")
if len(decls) == 1:
name = arg = decls[0]
name = name.replace("-", "_").lower()
else:
raise TypeError(
"Arguments take exactly one parameter declaration, got"
" {}".format(len(decls))
)
return name, [arg], []
[docs] def get_usage_pieces(self, ctx):
return [self.make_metavar()]
[docs] def get_error_hint(self, ctx):
return repr(self.make_metavar())
[docs] def add_to_parser(self, parser, ctx):
parser.add_argument(dest=self.name, nargs=self.nargs, obj=self)