httpie-cli/httpie/input.py
2013-04-12 11:59:23 -03:00

595 lines
18 KiB
Python

"""Parsing and processing of CLI input (args, auth credentials, files, stdin).
"""
import os
import sys
import re
import json
import mimetypes
import getpass
from io import BytesIO
from argparse import ArgumentParser, ArgumentTypeError, ArgumentError
try:
from collections import OrderedDict
except ImportError:
OrderedDict = dict
# TODO: Use MultiDict for headers once added to `requests`.
# https://github.com/jkbr/httpie/issues/130
from requests.structures import CaseInsensitiveDict
from .compat import urlsplit, str
HTTP_POST = 'POST'
HTTP_GET = 'GET'
HTTP = 'http://'
HTTPS = 'https://'
# 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
])
# Pretty
PRETTY_MAP = {
'all': ['format', 'colors'],
'colors': ['colors'],
'format': ['format'],
'none': []
}
PRETTY_STDOUT_TTY_ONLY = object()
# Defaults
OUTPUT_OPTIONS_DEFAULT = OUT_RESP_HEAD + OUT_RESP_BODY
OUTPUT_OPTIONS_DEFAULT_STDOUT_REDIRECTED = OUT_RESP_BODY
class Parser(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)
#noinspection PyMethodOverriding
def parse_args(self, env, args=None, namespace=None):
self.env = env
self.args, no_options = super(Parser, self)\
.parse_known_args(args, namespace)
if self.args.debug:
self.args.traceback = True
# Arguments processing and environment setup.
self._apply_no_options(no_options)
self._apply_config()
self._validate_download_options()
self._setup_standard_streams()
self._process_output_options()
self._process_pretty_options()
self._guess_method()
self._parse_items()
if not env.stdin_isatty:
self._body_from_file(self.env.stdin)
if not (self.args.url.startswith(HTTP)
or self.args.url.startswith(HTTPS)):
# Default to 'https://' if invoked as `https args`.
scheme = HTTPS if self.env.progname == 'https' else HTTP
self.args.url = scheme + self.args.url
self._process_auth()
return self.args
# noinspection PyShadowingBuiltins
def _print_message(self, message, file=None):
# Sneak in our stderr/stdout.
file = {
sys.stdout: self.env.stdout,
sys.stderr: self.env.stderr,
None: self.env.stderr
}.get(file, file)
super(Parser, self)._print_message(message, file)
def _setup_standard_streams(self):
"""
Modify `env.stdout` and `env.stdout_isatty` based on args, if needed.
"""
if not self.env.stdout_isatty and self.args.output_file:
self.error('Cannot use --output, -o with redirected output.')
# FIXME: Come up with a cleaner solution.
if self.args.download:
if not self.env.stdout_isatty:
# Use stdout as tge download output file.
self.args.output_file = self.env.stdout
# With `--download`, we write everything that would normally go to
# `stdout` to `stderr` instead. Let's replace the stream so that
# we don't have to use many `if`s throughout the codebase.
# The response body will be treated separately.
self.env.stdout = self.env.stderr
self.env.stdout_isatty = self.env.stderr_isatty
elif self.args.output_file:
# When not `--download`ing, then `--output` simply replaces
# `stdout`. The file is opened for appending, which isn't what
# we want in this case.
self.args.output_file.seek(0)
self.args.output_file.truncate()
self.env.stdout = self.args.output_file
self.env.stdout_isatty = False
def _apply_config(self):
if (not self.args.json
and self.env.config.implicit_content_type == 'form'):
self.args.form = True
def _process_auth(self):
"""
If only a username provided via --auth, then ask for a password.
Or, take credentials from the URL, if provided.
"""
url = urlsplit(self.args.url)
if self.args.auth:
if not self.args.auth.has_password():
# Stdin already read (if not a tty) so it's save to prompt.
self.args.auth.prompt_password(url.netloc)
elif url.username is not None:
# Handle http://username:password@hostname/
username, password = url.username, url.password
self.args.auth = AuthCredentials(
key=username,
value=password,
sep=SEP_CREDENTIALS,
orig=SEP_CREDENTIALS.join([username, password])
)
def _apply_no_options(self, no_options):
"""For every `--no-OPTION` in `no_options`, set `args.OPTION` to
its default value. This allows for un-setting of options, e.g.,
specified in config.
"""
invalid = []
for option in no_options:
if not option.startswith('--no-'):
invalid.append(option)
continue
# --no-option => --option
inverted = '--' + option[5:]
for action in self._actions:
if inverted in action.option_strings:
setattr(self.args, action.dest, action.default)
break
else:
invalid.append(option)
if invalid:
msg = 'unrecognized arguments: %s'
self.error(msg % ' '.join(invalid))
def _body_from_file(self, fd):
"""There can only be one source of request data.
Bytes are always read.
"""
if self.args.data:
self.error('Request body (from stdin or a file) and request '
'data (key=value) cannot be mixed.')
self.args.data = getattr(fd, 'buffer', fd).read()
def _guess_method(self):
"""Set `args.method` if not specified to either POST or GET
based on whether the request has data or not.
"""
if self.args.method is None:
# Invoked as `http URL'.
assert not self.args.items
if not self.env.stdin_isatty:
self.args.method = HTTP_POST
else:
self.args.method = HTTP_GET
# FIXME: False positive, e.g., "localhost" matches but is a valid URL.
elif not re.match('^[a-zA-Z]+$', self.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.
self.args.items.insert(
0,
KeyValueArgType(*SEP_GROUP_ITEMS).__call__(self.args.url)
)
except ArgumentTypeError as e:
if self.args.traceback:
raise
self.error(e.message)
else:
# Set the URL correctly
self.args.url = self.args.method
# Infer the method
has_data = not self.env.stdin_isatty or any(
item.sep in SEP_GROUP_DATA_ITEMS
for item in self.args.items
)
self.args.method = HTTP_POST if has_data else HTTP_GET
def _parse_items(self):
"""Parse `args.items` into `args.headers`, `args.data`, `args.params`,
and `args.files`.
"""
self.args.headers = CaseInsensitiveDict()
self.args.data = ParamDict() if self.args.form else OrderedDict()
self.args.files = OrderedDict()
self.args.params = ParamDict()
try:
parse_items(items=self.args.items,
headers=self.args.headers,
data=self.args.data,
files=self.args.files,
params=self.args.params)
except ParseError as e:
if self.args.traceback:
raise
self.error(e.message)
if self.args.files and not self.args.form:
# `http url @/path/to/file`
file_fields = list(self.args.files.keys())
if file_fields != ['']:
self.error(
'Invalid file fields (perhaps you meant --form?): %s'
% ','.join(file_fields))
fn, fd = self.args.files['']
self.args.files = {}
self._body_from_file(fd)
if 'Content-Type' not in self.args.headers:
mime, encoding = mimetypes.guess_type(fn, strict=False)
if mime:
content_type = mime
if encoding:
content_type = '%s; charset=%s' % (mime, encoding)
self.args.headers['Content-Type'] = content_type
def _process_output_options(self):
"""Apply defaults to output options, or validate the provided ones.
The default output options are stdout-type-sensitive.
"""
if not self.args.output_options:
self.args.output_options = (
OUTPUT_OPTIONS_DEFAULT
if self.env.stdout_isatty
else OUTPUT_OPTIONS_DEFAULT_STDOUT_REDIRECTED
)
unknown_output_options = set(self.args.output_options) - OUTPUT_OPTIONS
if unknown_output_options:
self.error(
'Unknown output options: %s' % ','.join(unknown_output_options)
)
if self.args.download and OUT_RESP_BODY in self.args.output_options:
# Response body is always downloaded with --download and it goes
# through a different routine, so we remove it.
self.args.output_options = str(
set(self.args.output_options) - set(OUT_RESP_BODY))
def _process_pretty_options(self):
if self.args.prettify == PRETTY_STDOUT_TTY_ONLY:
self.args.prettify = PRETTY_MAP[
'all' if self.env.stdout_isatty else 'none']
elif self.args.prettify and self.env.is_windows:
self.error('Only terminal output can be colorized on Windows.')
else:
# noinspection PyTypeChecker
self.args.prettify = PRETTY_MAP[self.args.prettify]
def _validate_download_options(self):
if not self.args.download:
if self.args.download_resume:
self.error('--continue only works with --download')
if self.args.download_resume and not (
self.args.download and self.args.output_file):
self.error('--continue requires --output to be specified')
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__
def session_name_arg_type(name):
from .sessions import Session
if not Session.is_valid_name(name):
raise ArgumentTypeError(
'special characters and spaces are not'
' allowed in session names: "%s"'
% name)
return name
class RegexValidator(object):
def __init__(self, pattern, error_message):
self.pattern = re.compile(pattern)
self.error_message = error_message
def __call__(self, value):
if not self.pattern.search(value):
raise ArgumentError(None, self.error_message)
return value
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 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, host):
try:
self.value = self._getpass(
'http: password for %s@%s: ' % (self.key, host))
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 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.
"""
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:
with open(os.path.expanduser(value), 'rb') as f:
value = (os.path.basename(value),
BytesIO(f.read()))
except IOError as e:
raise ParseError(
'Invalid argument "%s": %s' % (item.orig, e))
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