# Copyright 2013 Amazon.com, Inc. or its affiliates. All Rights Reserved.

#

# Licensed under the Apache License, Version 2.0 (the "License"). You

# may not use this file except in compliance with the License. A copy of

# the License is located at

#

# http://aws.amazon.com/apache2.0/

#

# or in the "license" file accompanying this file. This file is

# distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF

# ANY KIND, either express or implied. See the License for the specific

# language governing permissions and limitations under the License.

"""Module for processing CLI args."""

import os

import logging

from awscli.compat import six

from botocore.compat import OrderedDict, json

from awscli import SCALAR_TYPES, COMPLEX_TYPES

from awscli.paramfile import get_paramfile, ResourceLoadingError

from awscli.paramfile import PARAMFILE_DISABLED

from awscli import shorthand

LOG = logging.getLogger('awscli.argprocess')

class ParamError(Exception):

def __init__(self, cli_name, message):

"""

:type cli_name: string

:param cli_name: The complete cli argument name,

e.g. "--foo-bar". It should include the leading

hyphens if that's how a user would specify the name.

:type message: string

:param message: The error message to display to the user.

"""

full_message = ("Error parsing parameter '%s': %s" %

(cli_name, message))

super(ParamError, self).__init__(full_message)

self.cli_name = cli_name

self.message = message

class ParamSyntaxError(Exception):

pass

class ParamUnknownKeyError(Exception):

def __init__(self, key, valid_keys):

valid_keys = ', '.join(valid_keys)

full_message = (

"Unknown key '%s', valid choices "

"are: %s" % (key, valid_keys))

super(ParamUnknownKeyError, self).__init__(full_message)

class TooComplexError(Exception):

pass

def unpack_argument(session, service_name, operation_name, cli_argument, value):

"""

Unpack an argument's value from the commandline. This is part one of a two

step process in handling commandline arguments. Emits the load-cli-arg

event with service, operation, and parameter names. Example::

load-cli-arg.ec2.describe-instances.foo

"""

param_name = getattr(cli_argument, 'name', 'anonymous')

value_override = session.emit_first_non_none_response(

'load-cli-arg.%s.%s.%s' % (service_name,

operation_name,

param_name),

param=cli_argument, value=value, service_name=service_name,

operation_name=operation_name)

if value_override is not None:

value = value_override

return value

def uri_param(event_name, param, value, **kwargs):

"""Handler that supports param values from URIs.

"""

cli_argument = param

qualified_param_name = '.'.join(event_name.split('.')[1:])

if qualified_param_name in PARAMFILE_DISABLED or \

getattr(cli_argument, 'no_paramfile', None):

return

else:

return _check_for_uri_param(cli_argument, value)

def _check_for_uri_param(param, value):

if isinstance(value, list) and len(value) == 1:

value = value[0]

try:

return get_paramfile(value)

except ResourceLoadingError as e:

raise ParamError(param.cli_name, six.text_type(e))

def detect_shape_structure(param):

stack = []

return _detect_shape_structure(param, stack)

def _detect_shape_structure(param, stack):

if param.name in stack:

return 'recursive'

else:

stack.append(param.name)

try:

if param.type_name in SCALAR_TYPES:

return 'scalar'

elif param.type_name == 'structure':

sub_types = [_detect_shape_structure(p, stack)

for p in param.members.values()]

# We're distinguishing between structure(scalar)

# and structure(scalars), because for the case of

# a single scalar in a structure we can simplify

# more than a structure(scalars).

if len(sub_types) == 1 and all(p == 'scalar' for p in sub_types):

return 'structure(scalar)'

elif len(sub_types) > 1 and all(p == 'scalar' for p in sub_types):

return 'structure(scalars)'

else:

return 'structure(%s)' % ', '.join(sorted(set(sub_types)))

elif param.type_name == 'list':

return 'list-%s' % _detect_shape_structure(param.member, stack)

elif param.type_name == 'map':

if param.value.type_name in SCALAR_TYPES:

return 'map-scalar'

else:

return 'map-%s' % _detect_shape_structure(param.value, stack)

finally:

stack.pop()

def unpack_cli_arg(cli_argument, value):

"""

Parses and unpacks the encoded string command line parameter

and returns native Python data structures that can be passed

to the Operation.

:type cli_argument: :class:`awscli.arguments.BaseCLIArgument`

:param cli_argument: The CLI argument object.

:param value: The value of the parameter. This can be a number of

different python types (str, list, etc). This is the value as

it's specified on the command line.

:return: The "unpacked" argument than can be sent to the `Operation`

object in python.

"""

return _unpack_cli_arg(cli_argument.argument_model, value,

cli_argument.cli_name)

def _unpack_cli_arg(argument_model, value, cli_name):

if argument_model.type_name in SCALAR_TYPES:

return unpack_scalar_cli_arg(

argument_model, value, cli_name)

elif argument_model.type_name in COMPLEX_TYPES:

return _unpack_complex_cli_arg(

argument_model, value, cli_name)

else:

return six.text_type(value)

def _unpack_complex_cli_arg(argument_model, value, cli_name):

type_name = argument_model.type_name

if type_name == 'structure' or type_name == 'map':

if value.lstrip()[0] == '{':

try:

return json.loads(value, object_pairs_hook=OrderedDict)

except ValueError as e:

raise ParamError(

cli_name, "Invalid JSON: %s\nJSON received: %s"

% (e, value))

raise ParamError(cli_name, "Invalid JSON:\n%s" % value)

elif type_name == 'list':

if isinstance(value, six.string_types):

if value.lstrip()[0] == '[':

return json.loads(value, object_pairs_hook=OrderedDict)

elif isinstance(value, list) and len(value) == 1:

single_value = value[0].strip()

if single_value and single_value[0] == '[':

return json.loads(value[0], object_pairs_hook=OrderedDict)

try:

# There's a couple of cases remaining here.

# 1. It's possible that this is just a list of strings, i.e

# --security-group-ids sg-1 sg-2 sg-3 => ['sg-1', 'sg-2', 'sg-3']

# 2. It's possible this is a list of json objects:

# --filters '{"Name": ..}' '{"Name": ...}'

member_shape_model = argument_model.member

return [_unpack_cli_arg(member_shape_model, v, cli_name)

for v in value]

except (ValueError, TypeError) as e:

# The list params don't have a name/cli_name attached to them

# so they will have bad error messages. We're going to

# attach the parent parameter to this error message to provide

# a more helpful error message.

raise ParamError(cli_name, value[0])

def unpack_scalar_cli_arg(argument_model, value, cli_name=''):

# Note the cli_name is used strictly for error reporting. It's

# not required to use unpack_scalar_cli_arg

if argument_model.type_name == 'integer' or argument_model.type_name == 'long':

return int(value)

elif argument_model.type_name == 'float' or argument_model.type_name == 'double':

# TODO: losing precision on double types

return float(value)

elif argument_model.type_name == 'blob' and \

argument_model.serialization.get('streaming'):

file_path = os.path.expandvars(value)

file_path = os.path.expanduser(file_path)

if not os.path.isfile(file_path):

msg = 'Blob values must be a path to a file.'

raise ParamError(cli_name, msg)

return open(file_path, 'rb')

elif argument_model.type_name == 'boolean':

if isinstance(value, six.string_types) and value.lower() == 'false':

return False

return bool(value)

else:

return value

def _is_complex_shape(model):

if model.type_name not in ['structure', 'list', 'map']:

return False

elif model.type_name == 'list':

if model.member.type_name not in ['structure', 'list', 'map']:

return False

return True

class ParamShorthand(object):

def __init__(self):

self._parser = shorthand.ShorthandParser()

self._visitor = shorthand.BackCompatVisitor()

def __call__(self, cli_argument, value, **kwargs):

"""Attempt to parse shorthand syntax for values.

This is intended to be hooked up as an event handler (hence the

**kwargs). Given ``param`` object and its string ``value``,

figure out if we can parse it. If we can parse it, we return

the parsed value (typically some sort of python dict).

:type cli_argument: :class:`awscli.arguments.BaseCLIArgument`

:param cli_argument: The CLI argument object.

:type param: :class:`botocore.parameters.Parameter`

:param param: The parameter object (includes various metadata

about the parameter).

:type value: str

:param value: The value for the parameter type on the command

line, e.g ``--foo this_value``, value would be ``"this_value"``.

:returns: If we can parse the value we return the parsed value.

If it looks like JSON, we return None (which tells the event

emitter to use the default ``unpack_cli_arg`` provided that

no other event handlers can parsed the value). If we

run into an error parsing the value, a ``ParamError`` will

be raised.

"""

if not self._should_parse_as_shorthand(cli_argument, value):

return

else:

return self._parse_as_shorthand(cli_argument, value)

def _parse_as_shorthand(self, cli_argument, value):

try:

LOG.debug("Parsing param %s as shorthand",

cli_argument.cli_name)

handled_value = self._handle_special_cases(cli_argument, value)

if handled_value is not None:

return handled_value

if isinstance(value, list):

# Because of how we're using argparse, list shapes

# are configured with nargs='+' which means the ``value``

# is given to us "conveniently" as a list. When

# this happens we need to parse each list element

# individually.

parsed = [self._parser.parse(v) for v in value]

self._visitor.visit(parsed, cli_argument.argument_model)

else:

# Otherwise value is just a string.

parsed = self._parser.parse(value)

self._visitor.visit(parsed, cli_argument.argument_model)

except shorthand.ShorthandParseError as e:

raise ParamError(cli_argument.cli_name, str(e))

except (ParamError, ParamUnknownKeyError) as e:

# The shorthand parse methods don't have the cli_name,

# so any ParamError won't have this value. To accomodate

# this, ParamErrors are caught and reraised with the cli_name

# injected.

raise ParamError(cli_argument.cli_name, str(e))

return parsed

def _handle_special_cases(self, cli_argument, value):

# We need to handle a few special cases that the previous

# parser handled in order to stay backwards compatible.

model = cli_argument.argument_model

if model.type_name == 'list' and \

model.member.type_name == 'structure' and \

len(model.member.members) == 1:

# First special case is handling a list of structures

# of a single element such as:

#

# --instance-ids id-1 id-2 id-3

#

# gets parsed as:

#

# [{"InstanceId": "id-1"}, {"InstanceId": "id-2"},

# {"InstanceId": "id-3"}]

key_name = list(model.member.members.keys())[0]

new_values = [{key_name: v} for v in value]

return new_values

elif model.type_name == 'structure' and \

len(model.members) == 1 and \

'Value' in model.members and \

model.members['Value'].type_name == 'string' and \

'=' not in value:

# Second special case is where a structure of a single

# value whose member name is "Value" can be specified

# as:

# --instance-terminate-behavior shutdown

#

# gets parsed as:

# {"Value": "shutdown"}

return {'Value': value}

def _should_parse_as_shorthand(self, cli_argument, value):

# We first need to make sure this is a parameter that qualifies

# for simplification. The first short-circuit case is if it looks

# like json we immediately return.

if value and isinstance(value, list):

check_val = value[0]

else:

check_val = value

if isinstance(check_val, six.string_types) and check_val.strip().startswith(

('[', '{')):

LOG.debug("Param %s looks like JSON, not considered for "

"param shorthand.", cli_argument.py_name)

return False

model = cli_argument.argument_model

# The second case is to make sure the argument is sufficiently

# complex, that is, it's base type is a complex type *and*

# if it's a list, then it can't be a list of scalar types.

return _is_complex_shape(model)

class ParamShorthandDocGen(object):

"""Documentation generator for param shorthand syntax."""

_DONT_DOC = object()

_MAX_STACK = 3

def supports_shorthand(self, argument_model):

"""Checks if a CLI argument supports shorthand syntax."""

if argument_model is not None:

return _is_complex_shape(argument_model)

return False

def generate_shorthand_example(self, cli_name, argument_model):

"""Generate documentation for a CLI argument.

:type cli_argument: awscli.arguments.BaseCLIArgument

:param cli_argument: The CLI argument which to generate

documentation for.

:return: Returns either a string or ``None``. If a string

is returned, it is the generated shorthand example.

If a value of ``None`` is returned then this indicates

that no shorthand syntax is available for the provided

``argument_model``.

"""

docstring = self._handle_special_cases(cli_name, argument_model)

if docstring is self._DONT_DOC:

return None

elif docstring:

return docstring

# Otherwise we fall back to the normal docgen for shorthand

# syntax.

stack = []

try:

if argument_model.type_name == 'list':

argument_model = argument_model.member

return self._shorthand_docs(argument_model, stack) + ' ...'

else:

return self._shorthand_docs(argument_model, stack)

except TooComplexError:

return ''

def _handle_special_cases(self, cli_name, model):

if model.type_name == 'list' and \

model.member.type_name == 'structure' and \

len(model.member.members) == 1:

member_name = list(model.member.members)[0]

return '%s %s1 %s2 %s3' % (cli_name, member_name,

member_name, member_name)

elif model.type_name == 'structure' and \

len(model.members) == 1 and \

'Value' in model.members and \

model.members['Value'].type_name == 'string':

return self._DONT_DOC

return ''

def _shorthand_docs(self, argument_model, stack):

if len(stack) > self._MAX_STACK:

raise TooComplexError()

if argument_model.type_name == 'structure':

return self._structure_docs(argument_model, stack)

elif argument_model.type_name == 'list':

return self._list_docs(argument_model, stack)

elif argument_model.type_name == 'map':

return self._map_docs(argument_model, stack)

else:

return argument_model.type_name

def _list_docs(self, argument_model, stack):

list_member = argument_model.member

stack.append(list_member.name)

try:

element_docs = self._shorthand_docs(argument_model.member, stack)

finally:

stack.pop()

if list_member.type_name in COMPLEX_TYPES or len(stack) > 1:

return '[%s,%s]' % (element_docs, element_docs)

else:

return '%s,%s' % (element_docs, element_docs)

def _map_docs(self, argument_model, stack):

k = argument_model.key

value_docs = self._shorthand_docs(argument_model.value, stack)

start = 'KeyName1=%s,KeyName2=%s' % (value_docs, value_docs)

if k.enum and not stack:

start += '\n\nWhere valid key names are:\n'

for enum in k.enum:

start += ' %s\n' % enum

elif stack:

start = '{%s}' % start

return start

def _structure_docs(self, argument_model, stack):

parts = []

for name, member_shape in argument_model.members.items():

parts.append(self._member_docs(name, member_shape, stack))

inner_part = ','.join(parts)

if not stack:

return inner_part

return '{%s}' % inner_part

def _member_docs(self, name, shape, stack):

if stack.count(shape.name) > 0:

return '( ... recursive ... )'

stack.append(shape.name)

try:

value_doc = self._shorthand_docs(shape, stack)

finally:

stack.pop()

return '%s=%s' % (name, value_doc)