使用場景：

1) 爬蟲設(shè)置ip代理池時(shí)驗(yàn)證ip是否有效

2）進(jìn)行壓測時(shí)，進(jìn)行批量請(qǐng)求等等場景

grequests 利用 requests和gevent庫，做了一個(gè)簡單封裝，使用起來非常方便。

grequests.map(requests, stream=False, size=None, exception_handler=None, gtimeout=None)

另外，由于grequests底層使用的是requests，因此它支持

GET，OPTIONS， HEAD， POST， PUT， DELETE 等各種http method

所以以下的任務(wù)請(qǐng)求都是支持的

grequests.post(url, json={“name”:“zhangsan”})grequests.delete(url)

代碼如下:

import grequestsurls = [ ’http://www.baidu.com’, ’http://www.qq.com’, ’http://www.163.com’, ’http://www.zhihu.com’, ’http://www.toutiao.com’, ’http://www.douban.com’]rs = (grequests.get(u) for u in urls)print(grequests.map(rs)) # [<Response [200]>, None, <Response [200]>, None, None, <Response [418]>]def exception_handler(request, exception): print('Request failed')reqs = [ grequests.get(’http://httpbin.org/delay/1’, timeout=0.001), grequests.get(’http://fakedomain/’), grequests.get(’http://httpbin.org/status/500’)]print(grequests.map(reqs, exception_handler=exception_handler))

實(shí)際操作中，也可以自定義返回的結(jié)果

修改grequests源碼文件:

例如:

新增extract_item() 函數(shù)合修改map()函數(shù)

def extract_item(request): ''' 提取request的內(nèi)容 :param request: :return: ''' item = dict() item['url'] = request.url item['text'] = request.response.text or '' item['status_code'] = request.response.status_code or 0 return itemdef map(requests, stream=False, size=None, exception_handler=None, gtimeout=None): '''Concurrently converts a list of Requests to Responses. :param requests: a collection of Request objects. :param stream: If True, the content will not be downloaded immediately. :param size: Specifies the number of requests to make at a time. If None, no throttling occurs. :param exception_handler: Callback function, called when exception occured. Params: Request, Exception :param gtimeout: Gevent joinall timeout in seconds. (Note: unrelated to requests timeout) ''' requests = list(requests) pool = Pool(size) if size else None jobs = [send(r, pool, stream=stream) for r in requests] gevent.joinall(jobs, timeout=gtimeout) ret = [] for request in requests: if request.response is not None: ret.append(extract_item(request)) elif exception_handler and hasattr(request, ’exception’): ret.append(exception_handler(request, request.exception)) else: ret.append(None) yield ret

可以直接調(diào)用:

import grequestsurls = [ ’http://www.baidu.com’, ’http://www.qq.com’, ’http://www.163.com’, ’http://www.zhihu.com’, ’http://www.toutiao.com’, ’http://www.douban.com’]rs = (grequests.get(u) for u in urls)response_list = grequests.map(rs, gtimeout=10)for response in next(response_list): print(response)

支持事件鉤子

def print_url(r, *args, **kwargs):print(r.url)url = “http://www.baidu.com”res = requests.get(url, hooks={“response”: print_url})tasks = []req = grequests.get(url, callback=print_url)tasks.append(req)ress = grequests.map(tasks)print(ress)

以上就是本文的全部內(nèi)容，希望對(duì)大家的學(xué)習(xí)有所幫助，也希望大家多多支持好吧啦網(wǎng)。