class Crawler(object):
def __init__(self,threadnum,pathname,limit):
'''limit指定图片数目，path指定存放路径'''
super(Crawler, self).__init__()
self.threadPool = ThreadPool(threadnum)
self.file = PicFile('imgfile','r')
self.urlqueue = deque()
self.count = 1
self._makePath(pathname)
self.savaPath = os.getcwd()+'/'+pathname
self._getUrl(limit)
'''当前目录下创建指定目录'''
def _makePath(self,pathname):
if not os.path.isdir(os.getcwd()+'/'+pathname):
os.mkdir(os.getcwd()+'/'+pathname)
else:
pass
'''从文件取出 URL 到双向列表'''
def _getUrl(self,num):
while len(self.urlqueue) < num:
self.urlqueue.append(self.file.getData().rstrip('\n'))
self.file.close()
def start(self):
print '---start downloading picture---'
self.threadPool.startThreads()
while self.urlqueue!=deque([]):
self.threadPool.putTask(self._handleTask,self.urlqueue.popleft())
self.stop()
def stop(self):
self.threadPool.stopThreads()
print '---end downloading picture---'
'''任务处理'''
def _handleTask(self,url):
self._download(url)
'''下载图片,以数字升序命名'''
def _download(self,url):
retry = 2
try:
r = requests.get(url)
with open(self.savaPath +'/'+str(self.count)+'.jpg','wb') as jpg:
jpg.write(r.content)
self.count+=1
print url
except Exception,e:
if retry > 0:
retry = retry - 1
self._download(url)
def __init__(self,url,threadnum,limit):
#self.database = Database('pichref.sql')
self.file = PicFile('imgfile','a')
self.threadPool = ThreadPool(threadnum)
self.unaccesshref = deque()#双向列表
self.accessedhref = set()#已访问的链接集合
self.unaccesshref.append(url)#添加初始链接
self.limit = limit
self.picUrlCount = 1
def __init__(self,threadnum,pathname,limit):
'''limit指定图片数目，path指定存放路径'''
super(Crawler, self).__init__()
self.threadPool = ThreadPool(threadnum)
self.file = PicFile('imgfile','r')
self.urlqueue = deque()
self.count = 1
self._makePath(pathname)
self.savaPath = os.getcwd()+'/'+pathname
self._getUrl(limit)
class Fetch(object):
def __init__(self,url,threadnum,limit):
#self.database = Database('pichref.sql')
self.file = PicFile('imgfile','a')
self.threadPool = ThreadPool(threadnum)
self.unaccesshref = deque()#双向列表
self.accessedhref = set()#已访问的链接集合
self.unaccesshref.append(url)#添加初始链接
self.limit = limit
self.picUrlCount = 1
def start(self):
print '--start downloading url--'
self.threadPool.startThreads()
while self.unaccesshref!=deque([]):#不为空 一直分配任务
self._organise()
print '---'
self.stop()
def stop(self):
self.threadPool.stopThreads()
self.file.close()
print '--Stop downloading url--'
#往线程池分配任务
def _organise(self):
while self.unaccesshref:
url = self.unaccesshref.popleft()#从双向队列左取URL
#print 'popleft sucess'
self.threadPool.putTask(self._handle_task,url)#分配任务
self.accessedhref.add(url)#添加到已处理
time.sleep(2)#中断操作，让unaccesshref可以及时得到数据
print 'accessedhref',self.accessedhref
print 'unaccesshref',self.unaccesshref
#处理任务
def _handle_task(self,url):
webpage = DownloadWeb(url)
if webpage.download():
self._addUrlToUnaccesshref(webpage)
#添加普通链接到未访问链接列表
def _addUrlToUnaccesshref(self,webpage):
url, webpagecontent = webpage.getdata()
# pic_links, hrefs = self._getLinkFromPage(url,webpagecontent)
hrefs = self._getLinkFromPage(url,webpagecontent)
for href in hrefs:
if not self._isUsedhref(href):
self.unaccesshref.append(href)
# print 'self.unaccesshref',len(self.unaccesshref),self.unaccesshref,'\n'
#解析源码，获取普通链接和图片链接，将正确的图片链接存储到文件
def _getLinkFromPage(self,url,source_code):
pic_links, hrefs = [], []
soup = BeautifulSoup(source_code)
href_res = soup.find_all('a',href=True)#获取普通链接
pic_link_res = soup.find_all(src=re.compile('http://.*?\.jpg'))#获取图片链接
for h in href_res:
href = h.get('href').encode('utf-8')
if not href.startswith('http') and href!='/' and href!='#' and href.find(';')==-1:
href = urljoin(url, href)
hrefs.append(href)
for pic_link in pic_link_res:
pic_link = pic_link.get('src').encode('utf-8')
self.file.saveData(pic_link)#图片链接存储到文件
self.picUrlCount+=1
if self.picUrlCount >= self.limit:
# print self.limit,'limit ------'
# self.stop()
##由于线程池是当self.unaccesshref为空时才结束，当链接数满足要求，结束线程池的工作
self.unaccesshref=deque()
return []#
return hrefs
'''判断是否是已经获取的 url'''
def _isUsedhref(self,href):
if href in self.accessedhref or href in self.unaccesshref:
return True
else:
return False
