Application: gvSIG desktop » gvSIG scripting

from __future__ import absolute_import

import email.utils

import mimetypes

from .packages import six

def guess_content_type(filename, default='application/octet-stream'):

    """

    Guess the "Content-Type" of a file.

    :param filename:

        The filename to guess the "Content-Type" of using :mod:`mimetypes`.

    :param default:

        If no "Content-Type" can be guessed, default to `default`.

    """

    if filename:

        return mimetypes.guess_type(filename)[0] or default

    return default

def format_header_param(name, value):

    """

    Helper function to format and quote a single header parameter.

    Particularly useful for header parameters which might contain

    non-ASCII values, like file names. This follows RFC 2231, as

    suggested by RFC 2388 Section 4.4.

    :param name:

        The name of the parameter, a string expected to be ASCII only.

    :param value:

        The value of the parameter, provided as a unicode string.

    """

    if not any(ch in value for ch in '"\\\r\n'):

        result = '%s="%s"' % (name, value)

        try:

            result.encode('ascii')

        except UnicodeEncodeError:

            pass

        else:

            return result

    if not six.PY3:  # Python 2:

        value = value.encode('utf-8')

    value = email.utils.encode_rfc2231(value, 'utf-8')

    value = '%s*=%s' % (name, value)

    return value

class RequestField(object):

    """

    A data container for request body parameters.

    :param name:

        The name of this request field.

    :param data:

        The data/value body.

    :param filename:

        An optional filename of the request field.

    :param headers:

        An optional dict-like object of headers to initially use for the field.

    """

    def __init__(self, name, data, filename=None, headers=None):

        self._name = name

        self._filename = filename

        self.data = data

        self.headers = {}

        if headers:

            self.headers = dict(headers)

    @classmethod

    def from_tuples(cls, fieldname, value):

        """

        A :class:`~urllib3.fields.RequestField` factory from old-style tuple parameters.

        Supports constructing :class:`~urllib3.fields.RequestField` from

        parameter of key/value strings AND key/filetuple. A filetuple is a

        (filename, data, MIME type) tuple where the MIME type is optional.

        For example::

            'foo': 'bar',

            'fakefile': ('foofile.txt', 'contents of foofile'),

            'realfile': ('barfile.txt', open('realfile').read()),

            'typedfile': ('bazfile.bin', open('bazfile').read(), 'image/jpeg'),

            'nonamefile': 'contents of nonamefile field',

        Field names and filenames must be unicode.

        """

        if isinstance(value, tuple):

            if len(value) == 3:

                filename, data, content_type = value

            else:

                filename, data = value

                content_type = guess_content_type(filename)

        else:

            filename = None

            content_type = None

            data = value

        request_param = cls(fieldname, data, filename=filename)

        request_param.make_multipart(content_type=content_type)

        return request_param

    def _render_part(self, name, value):

        """

        Overridable helper function to format a single header parameter.

        :param name:

            The name of the parameter, a string expected to be ASCII only.

        :param value:

            The value of the parameter, provided as a unicode string.

        """

        return format_header_param(name, value)

    def _render_parts(self, header_parts):

        """

        Helper function to format and quote a single header.

        Useful for single headers that are composed of multiple items. E.g.,

        'Content-Disposition' fields.

        :param header_parts:

            A sequence of (k, v) typles or a :class:`dict` of (k, v) to format

            as `k1="v1"; k2="v2"; ...`.

        """

        parts = []

        iterable = header_parts

        if isinstance(header_parts, dict):

            iterable = header_parts.items()

        for name, value in iterable:

            if value:

                parts.append(self._render_part(name, value))

        return '; '.join(parts)

    def render_headers(self):

        """

        Renders the headers for this request field.

        """

        lines = []

        sort_keys = ['Content-Disposition', 'Content-Type', 'Content-Location']

        for sort_key in sort_keys:

            if self.headers.get(sort_key, False):

                lines.append('%s: %s' % (sort_key, self.headers[sort_key]))

        for header_name, header_value in self.headers.items():

            if header_name not in sort_keys:

                if header_value:

                    lines.append('%s: %s' % (header_name, header_value))

        lines.append('\r\n')

        return '\r\n'.join(lines)

    def make_multipart(self, content_disposition=None, content_type=None,

                       content_location=None):

        """

        Makes this request field into a multipart request field.

        This method overrides "Content-Disposition", "Content-Type" and

        "Content-Location" headers to the request parameter.

        :param content_type:

            The 'Content-Type' of the request body.

        :param content_location:

            The 'Content-Location' of the request body.

        """

        self.headers['Content-Disposition'] = content_disposition or 'form-data'

        self.headers['Content-Disposition'] += '; '.join([

            '', self._render_parts(

                (('name', self._name), ('filename', self._filename))

            )

        ])

        self.headers['Content-Type'] = content_type

        self.headers['Content-Location'] = content_location