python中数据爬虫requests库使用方法详解一、什么是Requests Requests 是Python语编写，基于urllib，采Apache2 Licensed开源协议的 HTTP 库。它urllib 更加方便，可以节约我们大量的工作，完全满足HTTP测试需求。一句话——requests是python实现的简单易用的HTTP库二、安装Requests库进入命令行win+R执行命令：pip install requests 项目导入：import requests 三、各种请求方式直接上代码，不明白可以查看我的urllib的基本使用方法 import requests requests.post('http://httpbin.org/post') requests.put('http://httpbin.org/put') requests.delete('http://httpbin.org/delete') requests.head('http://httpbin.org/get') requests.options('http://httpbin.org/get') 这么多请求方式，都有什么含义，所以问下度娘： GET：请求指定的页面信息，并返回实体主体。 HEAD：只请求页面的首部。 POST：请求服务器接受所指定的文档作为对所标识的URI的新的从属实体。 PUT：从客户端向服务器传送的数据取代指定的文档的内容。 DELETE：请求服务器删除指定的页面。 get 和 post比较常见 GET请求将提交的数据放置在HTTP请求协议头中 POST提交的数据则放在实体数据中（1）、基本的GET请求 import requests response = requests.get('http://httpbin.org/get') print(response.text) 返回值： { "args": {}, "headers": { "Accept": "*/*", "Accept-Encoding": "gzip, deflate", "Connection": "close", "Host": "httpbin.org", "User-Agent": "python-requests/2.18.4" }, "origin": "183.64.61.29", "url": "http://httpbin.org/get" } （2）、带参数的GET请求将name和age传进去 import requests response = requests.get("http://httpbin.org/get?name=germey&age=22") print(response.text) { "args": { "age": "22", "name": "germey" }, "headers": { "Accept": "*/*", "Accept-Encoding": "gzip, deflate", "Connection": "close", "Host": "httpbin.org", "User-Agent": "python-requests/2.18.4" }, "origin": "183.64.61.29", "url": "http://httpbin.org/get?name=germey&age=22" } 或者使用params的方法： import requests data = { 'name': 'germey', 'age': 22 } response = requests.get("http://httpbin.org/get", params=data) print(response.text) 返回值一样（3）、解析json 将返回值已json的形式展示： import requests import json response = requests.get("http://httpbin.org/get") print(type(response.text)) print(response.json()) print(json.loads(response.text)) print(type(response.json())) 返回值： {'args': {}, 'headers': {'Accept': '*/*', 'Accept-Encoding': 'gzip, deflate', 'Connection': 'close', 'Host': 'httpbin.org', 'User-Agent': 'python-requests/2.18.4'}, 'origin': '183.64.61.29', 'url': 'http://httpbin.org/get'} {'args': {}, 'headers': {'Accept': '*/*', 'Accept-Encoding': 'gzip, deflate', 'Connection': 'close', 'Host': 'httpbin.org', 'User-Agent': 'python-requests/2.18.4'}, 'origin': '183.64.61.29', 'url': 'http://httpbin.org/get'} （4）、获取二进制数据记住返回值.content就ok了 import requests response = requests.get("http://github.com/favicon.ico") print(type(response.text), type(response.content)) print(response.text) print(response.content) 返回值为二进制不必再进行展示，（5）、添加headers 有些网站访问时必须带有浏览器等信息，如果不传入headers就会报错，如下 import requests response = requests.get("http://www.zhihu.com/explore") print(response.text) 返回值：

500 Server Error

An internal server error occured. 当传入headers时： import requests headers = { 'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_4) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36' } response = requests.get("http://www.zhihu.com/explore", headers=headers) print(response.text) 成功返回网页源代码不做展示（6）、基本POST请求不明白见我博文urllib的使用方法 import requests data = {'name': 'germey', 'age': '22'} response = requests.post("http://httpbin.org/post", data=data) print(response.text) 返回： { "args": {}, "data": "", "files": {}, "form": { "age": "22", "name": "germey" }, "headers": { "Accept": "*/*", "Accept-Encoding": "gzip, deflate", "Connection": "close", "Content-Length": "18", "Content-Type": "application/x-www-form-urlencoded", "Host": "httpbin.org", "User-Agent": "python-requests/2.18.4" }, "json": null, "origin": "183.64.61.29", "url": "http://httpbin.org/post" } 三、响应 response属性 import requests response = requests.get('http://www.jianshu.com') print(type(response.status_code), response.status_code) print(type(response.headers), response.headers) print(type(response.cookies), response.cookies) print(type(response.url), response.url) print(type(response.history), response.history) return： 200 {'Date': 'Thu, 01 Feb 2018 20:47:08 GMT', 'Server': 'Tengine', 'Content-Type': 'text/html; charset=utf-8', 'Transfer-Encoding': 'chunked', 'X-Frame-Options': 'DENY', 'X-XSS-Protection': '1; mode=block', 'X-Content-Type-Options': 'nosniff', 'ETag': 'W/"9f70e869e7cce214b6e9d90f4ceaa53d"', 'Cache-Control': 'max-age=0, private, must-revalidate', 'Set-Cookie': 'locale=zh-CN; path=/', 'X-Request-Id': '366f4cba-8414-4841-bfe2-792aeb8cf302', 'X-Runtime': '0.008350', 'Content-Encoding': 'gzip', 'X-Via': '1.1 gjf22:8 (Cdn Cache Server V2.0), 1.1 PSzqstdx2ps251:10 (Cdn Cache Server V2.0)', 'Connection': 'keep-alive'} ]> http://www.jianshu.com/ [] 状态码判断：常见的网页状态码： 100: ('continue',), 101: ('switching_protocols',), 102: ('processing',), 103: ('checkpoint',), 122: ('uri_too_long', 'request_uri_too_long'), 200: ('ok', 'okay', 'all_ok', 'all_okay', 'all_good', '\\o/', '✓'), 201: ('created',), 202: ('accepted',), 203: ('non_authoritative_info', 'non_authoritative_information'), 204: ('no_content',), 205: ('reset_content', 'reset'), 206: ('partial_content', 'partial'), 207: ('multi_status', 'multiple_status', 'multi_stati', 'multiple_stati'), 208: ('already_reported',), 226: ('im_used',), # Redirection. 300: ('multiple_choices',), 301: ('moved_permanently', 'moved', '\\o-'), 302: ('found',), 303: ('see_other', 'other'), 304: ('not_modified',), 305: ('use_proxy',), 306: ('switch_proxy',), 307: ('temporary_redirect', 'temporary_moved', 'temporary'), 308: ('permanent_redirect', 'resume_incomplete', 'resume',), # These 2 to be removed in 3.0 # Client Error. 400: ('bad_request', 'bad'), 401: ('unauthorized',), 402: ('payment_required', 'payment'), 403: ('forbidden',), 404: ('not_found', '-o-'), 405: ('method_not_allowed', 'not_allowed'), 406: ('not_acceptable',), 407: ('proxy_authentication_required', 'proxy_auth', 'proxy_authentication'), 408: ('request_timeout', 'timeout'), 409: ('conflict',), 410: ('gone',), 411: ('length_required',), 412: ('precondition_failed', 'precondition'), 413: ('request_entity_too_large',), 414: ('request_uri_too_large',), 415: ('unsupported_media_type', 'unsupported_media', 'media_type'), 416: ('requested_range_not_satisfiable', 'requested_range', 'range_not_satisfiable'), 417: ('expectation_failed',), 418: ('im_a_teapot', 'teapot', 'i_am_a_teapot'), 421: ('misdirected_request',), 422: ('unprocessable_entity', 'unprocessable'), 423: ('locked',), 424: ('failed_dependency', 'dependency'), 425: ('unordered_collection', 'unordered'), 426: ('upgrade_required', 'upgrade'), 428: ('precondition_required', 'precondition'), 429: ('too_many_requests', 'too_many'), 431: ('header_fields_too_large', 'fields_too_large'), 444: ('no_response', 'none'), 449: ('retry_with', 'retry'), 450: ('blocked_by_windows_parental_controls', 'parental_controls'), 451: ('unavailable_for_legal_reasons', 'legal_reasons'), 499: ('client_closed_request',), # Server Error. 500: ('internal_server_error', 'server_error', '/o\\', '✗'), 501: ('not_implemented',), 502: ('bad_gateway',), 503: ('service_unavailable', 'unavailable'), 504: ('gateway_timeout',), 505: ('http_version_not_supported', 'http_version'), 506: ('variant_also_negotiates',), 507: ('insufficient_storage',), 509: ('bandwidth_limit_exceeded', 'bandwidth'), 510: ('not_extended',), 511: ('network_authentication_required', 'network_auth', 'network_authentication'), 四、高级操作（1）、文件上传使用 Requests 模块，上传文件也是如此简单的，文件的类型会自动进行处理：实例： import requests files = {'file': open('cookie.txt', 'rb')} response = requests.post("http://httpbin.org/post", files=files) print(response.text) 这是通过测试网站做的一个测试，返回值如下： { "args": {}, "data": "", "files": { "file": "#LWP-Cookies-2.0\r\nSet-Cookie3: BAIDUID=\"D2B4E137DE67E271D87F03A8A15DC459:FG=1\"; path=\"/\"; domain=\".baidu.com\"; path_spec; domain_dot; expires=\"2086-02-13 11:15:12Z\"; version=0\r\nSet-Cookie3: BIDUPSID=D2B4E137DE67E271D87F03A8A15DC459; path=\"/\"; domain=\".baidu.com\"; path_spec; domain_dot; expires=\"2086-02-13 11:15:12Z\"; version=0\r\nSet-Cookie3: H_PS_PSSID=25641_1465_21087_17001_22159; path=\"/\"; domain=\".baidu.com\"; path_spec; domain_dot; discard; version=0\r\nSet-Cookie3: PSTM=1516953672; path=\"/\"; domain=\".baidu.com\"; path_spec; domain_dot; expires=\"2086-02-13 11:15:12Z\"; version=0\r\nSet-Cookie3: BDSVRTM=0; path=\"/\"; domain=\"www.baidu.com\"; path_spec; discard; version=0\r\nSet-Cookie3: BD_HOME=0; path=\"/\"; domain=\"www.baidu.com\"; path_spec; discard; version=0\r\n" }, "form": {}, "headers": { "Accept": "*/*", "Accept-Encoding": "gzip, deflate", "Connection": "close", "Content-Length": "909", "Content-Type": "multipart/form-data; boundary=84835f570cfa44da8f4a062b097cad49", "Host": "httpbin.org", "User-Agent": "python-requests/2.18.4" }, "json": null, "origin": "183.64.61.29", "url": "http://httpbin.org/post" } （2）、获取cookie 当需要cookie时，直接调用response.cookie:(response为请求后的返回值) import requests response = requests.get("http://www.baidu.com") print(response.cookies) for key, value in response.cookies.items(): print(key + '=' + value) 输出结果： ]> BDORZ=27315 （3）、会话维持、模拟登陆如果某个响应中包含一些Cookie，你可以快速访问它们： import requests r = requests.get('http://www.google.com.hk/') print(r.cookies['NID']) print(tuple(r.cookies)) 要想发送你的cookies到服务器，可以使用 cookies 参数： import requests url = 'http://httpbin.org/cookies' cookies = {'testCookies_1': 'Hello_Python3', 'testCookies_2': 'Hello_Requests'} # 在Cookie Version 0中规定空格、方括号、圆括号、等于号、逗号、双引号、斜杠、问号、@，冒号，分号等特殊符号都不能作为Cookie的内容。 r = requests.get(url, cookies=cookies) print(r.json()) （4）、证书验证因为12306有一个错误证书，我们那它的网站做测试会出现下面的情况，证书不是官方证书，浏览器会识别出一个错误 import requests response = requests.get('http://www.12306.cn') print(response.status_code) 返回值：怎么正常进入这样的网站了，代码如下： import requests from requests.packages import urllib3 urllib3.disable_warnings() response = requests.get('http://www.12306.cn', verify=False) print(response.status_code) 将verify设置位False即可，返回的状态码为200 urllib3.disable_warnings()这条命令主要用于消除警告信息（5）、代理设置在进行爬虫爬取时，有时候爬虫会被服务器给屏蔽掉，这时采用的方法主要有降低访问时间，通过代理ip访问，如下： import requests proxies = { "http": "http://127.0.0.1:9743", "https": "http://127.0.0.1:9743", } response = requests.get("http://www.taobao.com", proxies=proxies) print(response.status_code) ip可以从网上抓取，或者某宝购买如果代理需要设置账户名和密码,只需要将字典更改为如下： proxies = { "http":"http://user:password@127.0.0.1:9999" } 如果你的代理是通过sokces这种方式则需要pip install "requests[socks]" proxies= { "http":"socks5://127.0.0.1:9999", "https":"sockes5://127.0.0.1:8888" } （6）、超时设置访问有些网站时可能会超时，这时设置好timeout就可以解决这个问题 import requests from requests.exceptions import ReadTimeout try: response = requests.get("http://httpbin.org/get", timeout = 0.5) print(response.status_code) except ReadTimeout: print('Timeout') 正常访问，状态吗返回200 （7）、认证设置如果碰到需要认证的网站可以通过requests.auth模块实现 import requests from requests.auth import HTTPBasicAuth response = requests.get("http://120.27.34.24:9001/",auth=HTTPBasicAuth("user","123")) print(response.status_code) 当然这里还有一种方式 import requests response = requests.get("http://120.27.34.24:9001/",auth=("user","123")) print(response.status_code) （8）、异常处理遇到网络问题（如：DNS查询失败、拒绝连接等）时，Requests会抛出一个ConnectionError 异常。遇到罕见的无效HTTP响应时，Requests则会抛出一个 HTTPError 异常。若请求超时，则抛出一个 Timeout 异常。若请求超过了设定的最大重定向次数，则会抛出一个 TooManyRedirects 异常。所有Requests显式抛出的异常都继承自 requests.exceptions.RequestException 。以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持中文源码网。