requests 是Python中一个非常出名的库,它极大的简化了 Python中进行HTTP请求的流程,我们来看一个简单的例子:
In [1]: import requests In [2]: requests.get("https://jiajunhuang.com") Out[2]:
只需要两行便可以发起一个HTTP请求,多么的简单。
针对HTTP协议的 GET
, POST
, PUT
, DELETE
等方法, requests
分别有:
requests.get requests.options requests.head requests.post requests.put requests.patch requests.delete
等对应的方法,他们都是 requests.request
的便捷版,也就是说,调用 requests.get
其实相当于调用 requests.request("GET", xxx)
。
接下来我们看看 requests.request
都能接受哪些参数,这其实也就是上述对应的 get
等方法能传入的参数:
def request(method, url, **kwargs): """Constructs and sends a :class:`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) ` 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 ` object :rtype: requests.Response Usage:: >>> import requests >>> req = requests.request('GET', 'https://httpbin.org/get') """ # 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)
我们来看看这些便捷函数的参数:
url
,这就是要请求的 url
,例如 https://jiajunhuang.com
,是必填的。params
是query string,它可以是一个字典,或者一个list,list的内容是一堆的tuple,也可以是bytes。data
是 HTTP
请求中的 body
,它可以是一个字典,或者一个list,list的内容是一堆的tuple,也可以是bytes或者文件json
是为了方便请求而提供的参数,它其实相当于 data
,但是会自动把请求的 Content-Type
设置为 application/json
headers
是 HTTP
请求中的头部,它是一个字典cookies
是所携带的 Cookie
,它可以是一个字典或者 CookieJar
的实例files
是要上传的文件,它可以是一个字典,字典的内容是tupleauth
用于开启 HTTP
请求的认证timeout
是超时时间allow_redirects
是否允许重定向,它是一个布尔值proxies
是是否使用代理verify
是否检查服务端的证书,传布尔值或者 CA
的路径stream
是布尔值,代表是否以流的方式读取结果cert
传入客户端的SSL证书而 requests
中, HTTP
请求的返回结果是 Response
的实例,包括方法:
json
用于把返回结果自动转换成 JSON
ok
用于检查返回的状态码是否是 400 以下,注意,ok是一个propertytext
用于以文本方式输出返回结果,注意,text是一个 property因此,我们可以看看常见的两种用法,一种是请求接口并且转换成 JSON
:
import requests resp = requests.get("https://api.jiajunhuang.com/v1/ip") print(resp.json())
另外一种是打印状态码并且打印出响应结果:
import requests resp = requests.get("https://api.jiajunhuang.com/v1/ip") print(resp.status_code) print(resp.text)