多线程爬虫可以用于抓取内容了这个可以提升性能了,这里我们来看php与python 线程池多线程爬虫的例子,代码如下:
php例子
<?phphtml' target='_blank'>class Connect extends Worker //worker模式{public function __construct(){}public function getConnection(){if (!self::$ch){self::$ch = curl_init();curl_setopt(self::$ch, CURLOPT_TIMEOUT, 2);curl_setopt(self::$ch, CURLOPT_RETURNTRANSFER, 1);curl_setopt(self::$ch, CURLOPT_HEADER, 0);curl_setopt(self::$ch, CURLOPT_NOSIGNAL, true);curl_setopt(self::$ch, CURLOPT_USERAGENT, "Firefox");curl_setopt(self::$ch, CURLOPT_FOLLOWLOCATION, 1);}/* do some exception/error stuff here maybe */return self::$ch;}public function closeConnection(){curl_close(self::$ch);}/*** Note that the link is stored statically, which for pthreads, means thread local* */protected static $ch;}class Query extends Threaded{public function __construct($url){$this->url = $url;}public function run(){$ch = $this->worker->getConnection();curl_setopt($ch, CURLOPT_URL, $this->url);$page = curl_exec($ch);$info = curl_getinfo($ch);$error = curl_error($ch);$this->deal_data($this->url, $page, $info, $error);$this->result = $page;}function deal_data($url, $page, $info, $error){$parts = explode(".", $url);$id = $parts[1];if ($info['http_code'] != 200){$this->show_msg($id, $error);} else{$this->show_msg($id, "OK");}}function show_msg($id, $msg){echo $id."/t$msg/n";}public function getResult(){return $this->result;}protected $url;protected $result;}function check_urls_multi_pthreads(){global $check_urls; //定义抓取的连接$check_urls = array( 'http://xxx.com' => "xx网",);$pool = new Pool(10, "Connect", array()); //建立10个线程池foreach ($check_urls as $url => $name){$pool->submit(new Query($url));}$pool->shutdown();}check_urls_multi_pthreads();python 多线程def handle(sid)://这个方法内执行爬虫数据处理passclass MyThread(Thread):"""docstring for ClassName"""def __init__(self, sid):Thread.__init__(self)self.sid = siddef run():handle(self.sid)threads = []for i in xrange(1,11):t = MyThread(i)threads.append(t)t.start()for t in threads:t.join()
python 线程池爬虫:
from queue import Queuefrom threading import Thread, Lockimport urllib.parseimport socketimport reimport timeseen_urls = set(['/'])lock = Lock()class Fetcher(Thread): def __init__(self, tasks): Thread.__init__(self) self.tasks = tasks self.daemon = True self.start() def run(self): while True: url = self.tasks.get() print(url) sock = socket.socket() sock.connect(('localhost', 3000)) get = 'GET {} HTTP/1.0/r/nHost: localhost/r/n/r/n'.format(url) sock.send(get.encode('ascii')) response = b'' chunk = sock.recv(4096) while chunk: response += chunk chunk = sock.recv(4096) links = self.parse_links(url, response) lock.acquire() for link in links.difference(seen_urls): self.tasks.put(link) seen_urls.update(links) lock.release() self.tasks.task_done() def parse_links(self, fetched_url, response): if not response: print('error: {}'.format(fetched_url)) return set() if not self._is_html(response): return set() urls = set(re.findall(r'''(?i)href=["']?([^/s"'<>]+)''', self.body(response))) links = set() for url in urls: normalized = urllib.parse.urljoin(fetched_url, url) parts = urllib.parse.urlparse(normalized) if parts.scheme not in ('', 'http', 'https'): continue host, port = urllib.parse.splitport(parts.netloc) if host and host.lower() not in ('localhost'): continue defragmented, frag = urllib.parse.urldefrag(parts.path) links.add(defragmented) return links def body(self, response): body = response.split(b'/r/n/r/n', 1)[1] return body.decode('utf-8') def _is_html(self, response): head, body = response.split(b'/r/n/r/n', 1) headers = dict(h.split(': ') for h in head.decode().split('/r/n')[1:]) return headers.get('Content-Type', '').startswith('text/html')class ThreadPool: def __init__(self, num_threads): self.tasks = Queue() for _ in range(num_threads): Fetcher(self.tasks) def add_task(self, url): self.tasks.put(url) def wait_completion(self): self.tasks.join()if __name__ == '__main__': start = time.time() pool = ThreadPool(4) pool.add_task("/") pool.wait_completion() print('{} URLs fetched in {:.1f} seconds'.format(len(seen_urls),time.time() - start))郑重声明:本文版权归原作者所有,转载文章仅为传播更多信息之目的,如作者信息标记有误,请第一时间联系我们修改或删除,多谢。
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