httpie-cli/httpie/input.py
2012-07-26 07:23:00 +02:00

431 lines
12 KiB
Python

"""Parsing and processing of CLI input (args, auth credentials, files, stdin).
"""
import os
import sys
import re
import json
import argparse
import mimetypes
import getpass
try:
from collections import OrderedDict
except ImportError:
OrderedDict = dict
from requests.structures import CaseInsensitiveDict
from requests.compat import str
from . import __version__
HTTP_POST = 'POST'
HTTP_GET = 'GET'
# Various separators used in args
SEP_HEADERS = ':'
SEP_CREDENTIALS = ':'
SEP_PROXY = ':'
SEP_DATA = '='
SEP_DATA_RAW_JSON = ':='
SEP_FILES = '@'
SEP_QUERY = '=='
# Separators that become request data
SEP_GROUP_DATA_ITEMS = frozenset([
SEP_DATA,
SEP_DATA_RAW_JSON,
SEP_FILES
])
# Separators allowed in ITEM arguments
SEP_GROUP_ITEMS = frozenset([
SEP_HEADERS,
SEP_QUERY,
SEP_DATA,
SEP_DATA_RAW_JSON,
SEP_FILES
])
# Output options
OUT_REQ_HEAD = 'H'
OUT_REQ_BODY = 'B'
OUT_RESP_HEAD = 'h'
OUT_RESP_BODY = 'b'
OUTPUT_OPTIONS = frozenset([
OUT_REQ_HEAD,
OUT_REQ_BODY,
OUT_RESP_HEAD,
OUT_RESP_BODY
])
# Defaults
OUTPUT_OPTIONS_DEFAULT = OUT_RESP_HEAD + OUT_RESP_BODY
OUTPUT_OPTIONS_DEFAULT_STDOUT_REDIRECTED = OUT_RESP_BODY
PRETTIFY_STDOUT_TTY_ONLY = object()
DEFAULT_UA = 'HTTPie/%s' % __version__
class Parser(argparse.ArgumentParser):
"""Adds additional logic to `argparse.ArgumentParser`.
Handles all input (CLI args, file args, stdin), applies defaults,
and performs extra validation.
"""
def __init__(self, *args, **kwargs):
kwargs['add_help'] = False
super(Parser, self).__init__(*args, **kwargs)
# Help only as --help (-h is used for --headers).
self.add_argument('--help',
action='help', default=argparse.SUPPRESS,
help=argparse._('show this help message and exit'))
#noinspection PyMethodOverriding
def parse_args(self, env, args=None, namespace=None):
args = super(Parser, self).parse_args(args, namespace)
self._process_output_options(args, env)
self._guess_method(args, env)
self._parse_items(args)
if not env.stdin_isatty:
self._body_from_file(args, env.stdin)
if args.auth and not args.auth.has_password():
# Stdin already read (if not a tty) so it's save to prompt.
args.auth.prompt_password()
return args
def _body_from_file(self, args, f):
"""Use the content of `f` as the `request.data`.
There can only be one source of request data.
"""
if args.data:
self.error('Request body (from stdin or a file) and request '
'data (key=value) cannot be mixed.')
args.data = f.read()
def _guess_method(self, args, env):
"""Set `args.method` if not specified to either POST or GET
based on whether the request has data or not.
"""
if args.method is None:
# Invoked as `http URL'.
assert not args.items
if not env.stdin_isatty:
args.method = HTTP_POST
else:
args.method = HTTP_GET
# FIXME: False positive, e.g., "localhost" matches but is a valid URL.
elif not re.match('^[a-zA-Z]+$', args.method):
# Invoked as `http URL item+'. The URL is now in `args.method`
# and the first ITEM is now incorrectly in `args.url`.
try:
# Parse the URL as an ITEM and store it as the first ITEM arg.
args.items.insert(
0, KeyValueArgType(*SEP_GROUP_ITEMS).__call__(args.url))
except argparse.ArgumentTypeError as e:
if args.traceback:
raise
self.error(e.message)
else:
# Set the URL correctly
args.url = args.method
# Infer the method
has_data = not env.stdin_isatty or any(
item.sep in SEP_GROUP_DATA_ITEMS for item in args.items)
args.method = HTTP_POST if has_data else HTTP_GET
def _parse_items(self, args):
"""Parse `args.items` into `args.headers`, `args.data`,
`args.`, and `args.files`.
"""
args.headers = CaseInsensitiveDict()
args.headers['User-Agent'] = DEFAULT_UA
args.data = ParamDict() if args.form else OrderedDict()
args.files = OrderedDict()
args.params = ParamDict()
try:
parse_items(items=args.items,
headers=args.headers,
data=args.data,
files=args.files,
params=args.params)
except ParseError as e:
if args.traceback:
raise
self.error(e.message)
if args.files and not args.form:
# `http url @/path/to/file`
# It's not --form so the file contents will be used as the
# body of the requests. Also, we try to detect the appropriate
# Content-Type.
if len(args.files) > 1:
self.error(
'Only one file can be specified unless'
' --form is used. File fields: %s'
% ','.join(args.files.keys()))
f = list(args.files.values())[0]
self._body_from_file(args, f)
# Reset files
args.files = {}
if 'Content-Type' not in args.headers:
mime, encoding = mimetypes.guess_type(f.name, strict=False)
if mime:
content_type = mime
if encoding:
content_type = '%s; charset=%s' % (mime, encoding)
args.headers['Content-Type'] = content_type
def _process_output_options(self, args, env):
"""Apply defaults to output options or validate the provided ones.
The default output options are stdout-type-sensitive.
"""
if not args.output_options:
args.output_options = (OUTPUT_OPTIONS_DEFAULT if env.stdout_isatty
else OUTPUT_OPTIONS_DEFAULT_STDOUT_REDIRECTED)
unknown = set(args.output_options) - OUTPUT_OPTIONS
if unknown:
self.error('Unknown output options: %s' % ','.join(unknown))
class ParseError(Exception):
pass
class KeyValue(object):
"""Base key-value pair parsed from CLI."""
def __init__(self, key, value, sep, orig):
self.key = key
self.value = value
self.sep = sep
self.orig = orig
def __eq__(self, other):
return self.__dict__ == other.__dict__
class KeyValueArgType(object):
"""A key-value pair argument type used with `argparse`.
Parses a key-value arg and constructs a `KeyValue` instance.
Used for headers, form data, and other key-value pair types.
"""
key_value_class = KeyValue
def __init__(self, *separators):
self.separators = separators
def __call__(self, string):
"""Parse `string` and return `self.key_value_class()` instance.
The best of `self.separators` is determined (first found, longest).
Back slash escaped characters aren't considered as separators
(or parts thereof). Literal back slash characters have to be escaped
as well (r'\\').
"""
class Escaped(str):
"""Represents an escaped character."""
def tokenize(s):
"""Tokenize `s`. There are only two token types - strings
and escaped characters:
>>> tokenize(r'foo\=bar\\baz')
['foo', Escaped('='), 'bar', Escaped('\\'), 'baz']
"""
tokens = ['']
esc = False
for c in s:
if esc:
tokens.extend([Escaped(c), ''])
esc = False
else:
if c == '\\':
esc = True
else:
tokens[-1] += c
return tokens
tokens = tokenize(string)
# Sorting by length ensures that the longest one will be
# chosen as it will overwrite any shorter ones starting
# at the same position in the `found` dictionary.
separators = sorted(self.separators, key=len)
for i, token in enumerate(tokens):
if isinstance(token, Escaped):
continue
found = {}
for sep in separators:
pos = token.find(sep)
if pos != -1:
found[pos] = sep
if found:
# Starting first, longest separator found.
sep = found[min(found.keys())]
key, value = token.split(sep, 1)
# Any preceding tokens are part of the key.
key = ''.join(tokens[:i]) + key
# Any following tokens are part of the value.
value += ''.join(tokens[i + 1:])
break
else:
raise argparse.ArgumentTypeError(
'"%s" is not a valid value' % string)
return self.key_value_class(
key=key, value=value, sep=sep, orig=string)
class AuthCredentials(KeyValue):
"""Represents parsed credentials."""
def _getpass(self, prompt):
# To allow mocking.
return getpass.getpass(prompt)
def has_password(self):
return self.value is not None
def prompt_password(self):
try:
self.value = self._getpass("Password for user '%s': " % self.key)
except (EOFError, KeyboardInterrupt):
sys.stderr.write('\n')
sys.exit(0)
class AuthCredentialsArgType(KeyValueArgType):
"""A key-value arg type that parses credentials."""
key_value_class = AuthCredentials
def __call__(self, string):
"""Parse credentials from `string`.
("username" or "username:password").
"""
try:
return super(AuthCredentialsArgType, self).__call__(string)
except argparse.ArgumentTypeError:
# No password provided, will prompt for it later.
return self.key_value_class(
key=string,
value=None,
sep=SEP_CREDENTIALS,
orig=string
)
class ParamDict(OrderedDict):
"""Multi-value dict for URL parameters and form data."""
#noinspection PyMethodOverriding
def __setitem__(self, key, value):
""" If `key` is assigned more than once, `self[key]` holds a
`list` of all the values.
This allows having multiple fields with the same name in form
data and URL params.
"""
# NOTE: Won't work when used for form data with multiple values
# for a field and a file field is present:
# https://github.com/kennethreitz/requests/issues/737
if key not in self:
super(ParamDict, self).__setitem__(key, value)
else:
if not isinstance(self[key], list):
super(ParamDict, self).__setitem__(key, [self[key]])
self[key].append(value)
def parse_items(items, data=None, headers=None, files=None, params=None):
"""Parse `KeyValue` `items` into `data`, `headers`, `files`,
and `params`.
"""
if headers is None:
headers = CaseInsensitiveDict()
if data is None:
data = OrderedDict()
if files is None:
files = OrderedDict()
if params is None:
params = ParamDict()
for item in items:
value = item.value
key = item.key
if item.sep == SEP_HEADERS:
target = headers
elif item.sep == SEP_QUERY:
target = params
elif item.sep == SEP_FILES:
try:
value = open(os.path.expanduser(item.value), 'r')
except IOError as e:
raise ParseError(
'Invalid argument "%s": %s' % (item.orig, e))
if not key:
key = os.path.basename(value.name)
target = files
elif item.sep in [SEP_DATA, SEP_DATA_RAW_JSON]:
if item.sep == SEP_DATA_RAW_JSON:
try:
value = json.loads(item.value)
except ValueError:
raise ParseError('"%s" is not valid JSON' % item.orig)
target = data
else:
raise TypeError(item)
target[key] = value
return headers, data, files, params