原文地址：http://www.lihuai.net/program/python/1617.html
Python Requests库：HTTP for Humans
时间: 2014/12/30 | 分类: Python | 作者: 李坏 | 浏览：287 | 抢沙发
Python标准库中用来处理HTTP的模块是urllib2，不过其中的API太零碎了，requests是更简单更人性化的第三方库。
用pip下载：
pip install requests
或者git：
git clone git://github.com/kennethreitz/requests.git
发送请求：
GET方法
>>> import requests >>> r = requests.get(‘https://api.github.com/events‘) POST方法： >>> r = requests.post("http://httpbin.org/post") 也可以使用其它方法： >>> r = requests.put("http://httpbin.org/put") >>> r = requests.delete("http://httpbin.org/delete") >>> r = requests.head("http://httpbin.org/get") >>> r = requests.options("http://httpbin.org/get")
也可以将请求方法放在参数中：
>>> import requests >>> req = requests.request(‘GET‘, ‘http://httpbin.org/get‘)
传递参数或上传文件：
1.如果要将参数放在url中传递，使用params参数，可以是字典或者字符串：
>>> payload = {‘key1‘: ‘value1‘, ‘key2‘: ‘value2‘}
>>> r = requests.get("http://httpbin.org/get", params=payload)
>>> r.url
u‘http://httpbin.org/get?key2=value2&key1=value1‘
2.如果要将参数放在request body中传递，使用data参数，可以是字典，字符串或者是类文件对象。
使用字典时将发送form-encoded data：
>>> payload = {‘key1‘: ‘value1‘, ‘key2‘: ‘value2‘}
>>> r = requests.post("http://httpbin.org/post", data=payload)
>>> print(r.text)
{
...
"form": {
"key2": "value2",
"key1": "value1"
},
...
}
使用字符串时将直接发送数据：
>>> import json >>> url = ‘https://api.github.com/some/endpoint‘ >>> payload = {‘some‘: ‘data‘} >>> r = requests.post(url, data=json.dumps(payload))
流上传：
with open(‘massive-body‘, ‘rb‘) as f: requests.post(‘http://some.url/streamed‘, data=f) Chunk-Encoded上传： def gen(): yield ‘hi‘ yield ‘there‘ requests.post(‘http://some.url/chunked‘, data=gen())
3.如果要上传文件，可以使用file参数发送Multipart-encoded数据，file参数是{ ‘name’: file-like-objects}格式的字典 (or {‘name’:(‘filename’, fileobj)}) ：
>>> url = ‘http://httpbin.org/post‘ >>> files = {‘file‘: open(‘report.xls‘, ‘rb‘)} >>> r = requests.post(url, files=files) >>> r.text { ... "files": { "file": "<censored...binary...data>" }, ... }
也可以明确设置filename, content_type and headers：
>>> url = ‘http://httpbin.org/post‘ >>> files = {‘file‘: (‘report.xls‘, open(‘report.xls‘, ‘rb‘), ‘application/vnd.ms-excel‘, {‘Expires‘: ‘0‘})} >>> r = requests.post(url, files=files) >>> print r.text { "args": {}, "data": "", "files": { "file": "1\t2\r\n" }, "form": {}, "headers": { "Content-Type": "multipart/form-data; boundary=e0f9ff1303b841498ae53a903f27e565", "Host": "httpbin.org", "User-Agent": "python-requests/2.2.1 CPython/2.7.3 Windows/7", }, "url": "http://httpbin.org/post" }
一次性上传多个文件：
>>> url = ‘http://httpbin.org/post‘ >>> multiple_files = [(‘images‘, (‘foo.png‘, open(‘foo.png‘, ‘rb‘), ‘image/png‘)), (‘images‘, (‘bar.png‘, open(‘bar.png‘, ‘rb‘), ‘image/png‘))] >>> r = requests.post(url, files=multiple_files) >>> r.text { ... ‘files‘: {‘images‘: ‘data:image/png;base64,iVBORw ....‘} ‘Content-Type‘: ‘multipart/form-data; boundary=3131623adb2043caaeb5538cc7aa0b3a‘, ... }
设置Headers
>>> import json >>> url = ‘https://api.github.com/some/endpoint‘ >>> payload = {‘some‘: ‘data‘} >>> headers = {‘content-type‘: ‘application/json‘} >>> r = requests.post(url, data=json.dumps(payload), headers=headers)
Response对象：
获取unicode字符串，会自动根据响应头部的字符编码(r.encoding)进行解码，当然也可以自己设定r.encoding：
>>> r = requests.get(‘https://github.com/timeline.json‘) >>> r.text u‘{"message":"Hello there, wayfaring stranger...
获取bytes字符串，会自动解码gzip和deflate数据：
>>> r.content ‘{"message":"Hello there, wayfaring stranger. ..
要存储web图片，可以：
>>> from PIL import Image >>> from StringIO import StringIO >>> i = Image.open(StringIO(r.content))
可以解码json对象：
>>> r.json() {u‘documentation_url‘: u‘https://developer... 返回raw response，需要在requests请求中将stream设为True： >>> r = requests.get(‘https://github.com/timeline.json‘, stream=True) >>> r.raw <requests.packages.urllib3.response.HTTPResponse object at 0x101194810> >>> r.raw.read(10) ‘\x1f\x8b\x08\x00\x00\x00\x00\x00\x00\x03‘
如果不想一次性处理全部的数据，可以：
tarball_url = ‘https://github.com/kennethreitz/requests/tarball/master‘ r = requests.get(tarball_url, stream=True) if int(r.headers[‘content-length‘]) < TOO_LONG: content = r.content ...
也可以迭代的处理数据：
with open(filename, ‘wb‘) as fd: for chunk in r.iter_content(chunk_size): fd.write(chunk)
或者：
import json import requests r = requests.get(‘http://httpbin.org/stream/20‘, stream=True) for line in r.iter_lines(): # filter out keep-alive new lines if line: print(json.loads(line))
获取响应代码：
>>> r = requests.get(‘http://httpbin.org/get‘) >>> r.status_code 200
获取响应headers：
>>> r.headers { ‘content-encoding‘: ‘gzip‘, ‘transfer-encoding‘: ‘chunked‘, ‘connection‘: ‘close‘, ‘server‘: ‘nginx/1.0.4‘, ‘x-runtime‘: ‘148ms‘, ‘etag‘: ‘"e1ca502697e5c9317743dc078f67693f"‘, ‘content-type‘: ‘application/json‘ }
获取发送的headers
>>> r.request.headers {‘Accept-Encoding‘: ‘identity, deflate, compress, gzip‘, ‘Accept‘: ‘*/*‘, ‘User-Agent‘: ‘python-requests/1.2.0‘} Cookie
获取cookie，返回CookieJar对象： >>> url = ‘http://www.baidu.com‘ >>> r = requests.get(url) >>> r.cookies
将CookieJar转为字典：
>>> requests.utils.dict_from_cookiejar(r.cookies) {‘BAIDUID‘: ‘84722199DF8EDC372D549EC56CA1A0E2:FG=1‘, ‘BD_HOME‘: ‘0‘, ‘BDSVRTM‘: ‘0‘}
将字典转为CookieJar：
requests.utils.cookiejar_from_dict(cookie_dict, cookiejar=None, overwrite=True)
上传自己设置的cookie，使用cookies参数，可以是字典或者CookieJar对象：
>>> url = ‘http://httpbin.org/cookies‘ >>> cookies = dict(cookies_are=‘working‘) >>> r = requests.get(url, cookies=cookies) >>> r.text ‘{"cookies": {"cookies_are": "working"}}‘
如果需要在会话中保留cookie，需要用到后面要说的Session。
Redirection and History
可以用history属性来追踪redirection
>>> r = requests.get(‘http://github.com‘) >>> r.url ‘https://github.com/‘ >>> r.status_code 200 >>> r.history [<Response [301]>] Session
要在会话中保留状态，可以使用request.Session()。
Session可以使用get，post等方法，Session对象在请求时允许你保留一定的参数和自动设置cookie
s = requests.Session() s.get(‘http://httpbin.org/cookies/set/sessioncookie/123456789‘) #cookie保留在s中 r = s.get("http://httpbin.org/cookies") #再次访问时会保留cookie print(r.text) # ‘{"cookies": {"sessioncookie": "123456789"}}‘
也可以自己设置headers，cookies：
s = requests.Session() s.auth = (‘user‘, ‘pass‘) s.headers.update({‘x-test‘: ‘true‘}) s.get(‘http://httpbin.org/headers‘, headers={‘x-test2‘: ‘true‘}) # ‘x-test‘ and ‘x-test2‘ 都会被发送
预设Request
可以在发送request前做些额外的设定
from requests import Request, Session s = Session() req = Request(‘GET‘, url, data=data, headers=header ) prepped = req.prepare() # do something with prepped.body # do something with prepped.headers resp = s.send(prepped, stream=stream, verify=verify, proxies=proxies, cert=cert, timeout=timeout ) print(resp.status_code)
验证
Basic Authentication
>>> from requests.auth import HTTPBasicAuth >>> requests.get(‘https://api.github.com/user‘, auth=HTTPBasicAuth(‘user‘, ‘pass‘)) <Response [200]>
因为HTTP Basic Auth很常用，所以也可以直接验证：
>>> requests.get(‘https://api.github.com/user‘, auth=(‘user‘, ‘pass‘)) <Response [200]> Digest Authentication >>> from requests.auth import HTTPDigestAuth >>> url = ‘http://httpbin.org/digest-auth/auth/user/pass‘ >>> requests.get(url, auth=HTTPDigestAuth(‘user‘, ‘pass‘)) <Response [200]> OAuth 1 Authentication >>> import requests >>> from requests_oauthlib import OAuth1 >>> url = ‘https://api.twitter.com/1.1/account/verify_credentials.json‘ >>> auth = OAuth1(‘YOUR_APP_KEY‘, ‘YOUR_APP_SECRET‘, ‘USER_OAUTH_TOKEN‘, ‘USER_OAUTH_TOKEN_SECRET‘) >>> requests.get(url, auth=auth) <Response [200]> 也可以使用自己写的验证类。比如某个web服务接受将X-Pizza报头设置成密码的验证，可以这样写验证类： from requests.auth import AuthBase class PizzaAuth(AuthBase): """Attaches HTTP Pizza Authentication to the given Request object.""" def __init__(self, username): # setup any auth-related data here self.username = username def __call__(self, r): # modify and return the request r.headers[‘X-Pizza‘] = self.username return r
使用：
>>> requests.get(‘http://pizzabin.org/admin‘, auth=PizzaAuth(‘kenneth‘)) <Response [200]>
SSL证书验证
检查主机的ssl证书：
>>> requests.get(‘https://kennethreitz.com‘, verify=True) raise ConnectionError(e) ConnectionError: HTTPSConnectionPool(host=‘kennethreitz.com‘, port=443): Max retries exceeded with url: / (Caused by <class ‘socket.error‘>: [Errno 10061] )
github是有的：
>>> requests.get(‘https://github.com‘, verify=True) <Response [200]>
如果你设置验证设置为False，也可以忽略验证SSL证书。
可以读取验证文件：
>>> requests.get(‘https://kennethreitz.com‘, cert=(‘/path/server.crt‘, ‘/path/key‘))
代理
使用代理：
import requests proxies = { "http": "http://10.10.1.10:3128", "https": "http://10.10.1.10:1080", } requests.get("http://example.org", proxies=proxies)
可以设置环境变量：
$ export HTTP_PROXY="http://10.10.1.10:3128" $ export HTTPS_PROXY="http://10.10.1.10:1080" $ python >>> import requests >>> requests.get("http://example.org")
如果代理需要验证：
proxies = { "http": "http://user:pass@10.10.1.10:3128/", }
