blog/source/_posts/python-request.md

---

title: python_request date: 2019-05-08 15:53:14 tags: [python,reptile]

categories: [python,reptile]

python requests

requests 是出入python时就接触的网路请求神器，在学习了这么久后总结一些经验保存、学习。 这也是第一个python博客，顺便吐槽下 python的源码 注释真少 = = 好多都必须得看doc才能了解

安装

pip install requests
or
conda install requests (Anaconda)

用法

# -*- coding: utf-8 -*-

"""
requests.api
~~~~~~~~~~~~

This module implements the Requests API.

:copyright: (c) 2012 by Kenneth Reitz.
:license: Apache2, see LICENSE for more details.
"""

from . import sessions


def request(method, url, **kwargs):
    """Constructs and sends a :class:`Request <Request>`.

    :param method: method for the new :class:`Request` object.
    :param url: URL for the new :class:`Request` object.
    :param params: (optional) Dictionary, list of tuples or bytes to send
        in the body of the :class:`Request`.
    :param data: (optional) Dictionary, list of tuples, bytes, or file-like
        object to send in the body of the :class:`Request`.
    :param json: (optional) A JSON serializable Python object to send in the body of the :class:`Request`.
    :param headers: (optional) Dictionary of HTTP Headers to send with the :class:`Request`.
    :param cookies: (optional) Dict or CookieJar object to send with the :class:`Request`.
    :param files: (optional) Dictionary of ``'name': file-like-objects`` (or ``{'name': file-tuple}``) for multipart encoding upload.
        ``file-tuple`` can be a 2-tuple ``('filename', fileobj)``, 3-tuple ``('filename', fileobj, 'content_type')``
        or a 4-tuple ``('filename', fileobj, 'content_type', custom_headers)``, where ``'content-type'`` is a string
        defining the content type of the given file and ``custom_headers`` a dict-like object containing additional headers
        to add for the file.
    :param auth: (optional) Auth tuple to enable Basic/Digest/Custom HTTP Auth.
    :param timeout: (optional) How many seconds to wait for the server to send data
        before giving up, as a float, or a :ref:`(connect timeout, read
        timeout) <timeouts>` tuple.
    :type timeout: float or tuple
    :param allow_redirects: (optional) Boolean. Enable/disable GET/OPTIONS/POST/PUT/PATCH/DELETE/HEAD redirection. Defaults to ``True``.
    :type allow_redirects: bool
    :param proxies: (optional) Dictionary mapping protocol to the URL of the proxy.
    :param verify: (optional) Either a boolean, in which case it controls whether we verify
            the server's TLS certificate, or a string, in which case it must be a path
            to a CA bundle to use. Defaults to ``True``.
    :param stream: (optional) if ``False``, the response content will be immediately downloaded.
    :param cert: (optional) if String, path to ssl client cert file (.pem). If Tuple, ('cert', 'key') pair.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response

    Usage::

      >>> import requests
      >>> req = requests.request('GET', 'https://httpbin.org/get')
      <Response [200]>
    """

    # By using the 'with' statement we are sure the session is closed, thus we
    # avoid leaving sockets open which can trigger a ResourceWarning in some
    # cases, and look like a memory leak in others.
    with sessions.Session() as session:
        return session.request(method=method, url=url, **kwargs)


def get(url, params=None, **kwargs):
    r"""Sends a GET request.

    :param url: URL for the new :class:`Request` object.
    :param params: (optional) Dictionary, list of tuples or bytes to send
        in the body of the :class:`Request`.
    :param \*\*kwargs: Optional arguments that ``request`` takes.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response
    """

    kwargs.setdefault('allow_redirects', True)
    return request('get', url, params=params, **kwargs)


def options(url, **kwargs):
    r"""Sends an OPTIONS request.

    :param url: URL for the new :class:`Request` object.
    :param \*\*kwargs: Optional arguments that ``request`` takes.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response
    """

    kwargs.setdefault('allow_redirects', True)
    return request('options', url, **kwargs)


def head(url, **kwargs):
    r"""Sends a HEAD request.

    :param url: URL for the new :class:`Request` object.
    :param \*\*kwargs: Optional arguments that ``request`` takes.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response
    """

    kwargs.setdefault('allow_redirects', False)
    return request('head', url, **kwargs)


def post(url, data=None, json=None, **kwargs):
    r"""Sends a POST request.

    :param url: URL for the new :class:`Request` object.
    :param data: (optional) Dictionary, list of tuples, bytes, or file-like
        object to send in the body of the :class:`Request`.
    :param json: (optional) json data to send in the body of the :class:`Request`.
    :param \*\*kwargs: Optional arguments that ``request`` takes.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response
    """

    return request('post', url, data=data, json=json, **kwargs)


def put(url, data=None, **kwargs):
    r"""Sends a PUT request.

    :param url: URL for the new :class:`Request` object.
    :param data: (optional) Dictionary, list of tuples, bytes, or file-like
        object to send in the body of the :class:`Request`.
    :param json: (optional) json data to send in the body of the :class:`Request`.
    :param \*\*kwargs: Optional arguments that ``request`` takes.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response
    """

    return request('put', url, data=data, **kwargs)


def patch(url, data=None, **kwargs):
    r"""Sends a PATCH request.

    :param url: URL for the new :class:`Request` object.
    :param data: (optional) Dictionary, list of tuples, bytes, or file-like
        object to send in the body of the :class:`Request`.
    :param json: (optional) json data to send in the body of the :class:`Request`.
    :param \*\*kwargs: Optional arguments that ``request`` takes.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response
    """

    return request('patch', url, data=data, **kwargs)


def delete(url, **kwargs):
    r"""Sends a DELETE request.

    :param url: URL for the new :class:`Request` object.
    :param \*\*kwargs: Optional arguments that ``request`` takes.
    :return: :class:`Response <Response>` object
    :rtype: requests.Response
    """

    return request('delete', url, **kwargs)

包中已经包含了常用的几种请求方式，例如 GET/POST/PUT/DELETE等

传参

这部分是最主要的部分，判断合适的请求方式并且修改拼接参数对数据进行爬取。

重要参数

• param 用于 GET 请求

• data 用于 application/x-www-form-urlencoded 格式数据

• json 用于 application/json 格式数据

• files 用于 multipart/form-data 格式数据

eg.混合传参分别写

其他参数

• header 头信息
• cookies 身份认证信息等
• timeout 超时
• proxies 代理
• verify TLS 校验

返回数据

返回数据可以直接通过text拿到文本数据，如果是json数据可直接通过json() 获取

更多用法可查看官网文档 🔗

这里推荐一个开源项目，堪称神器 可以把curl请求转为请求，部分时候参数需要调整这个用上面提到的方法就可尝试。(https://curl.trillworks.com/)

下篇写拿到返回数据如何提取和处理