def get(self):
url = self.request.get("url")
if not url:
self.response.out.write("download?url=file_url")
return
mixed_result = self.check_exist_and_sustainable(url)
if mixed_result == None:
self.response.out.write('error: url resource not found, or network error.')
return
if mixed_result == False:
self.response.out.write('error: url resource cannot support continually download.')
# todo small file download
return
# else result is a size
try:
filename, size, mimetype = mixed_result
except:
self.response.out.write('internal error: function "check_exist_and_sustainable" returned %s.' %str(mixed_result))
return
# got file size
if size > 500*1024*1024:
self.response.out.write('要下载的文件太大了(超过500MB),单个app承受不起啊(每天就1G流量..),正在计划搭建下载均衡器,请关注.<br><a href="list">返回</a>')
return
# calculate block_number
block_number = calc_block_number(size)
# create file record
from model import EStatus, File
from google.appengine.api import users
downloader = users.get_current_user()
new_file = File.get_or_insert('%s-%s'%(downloader, url), name = filename, url = url, downloader = downloader, size = size, mimetype = mimetype, status = EStatus.DOWNLOADING)
new_file.put()
key = new_file.key()
from google.appengine.api import taskqueue
def add_task():
# add task
for n in range(block_number):
if n == block_number - 1: last = 'true'
else: last = ''
try:
taskqueue.add(url='/downloadfileblock', queue_name=conf.DOWNLOAD_FILEBLOCK_QUEUE_NAME, method='GET', params={'url': url, 'key': key, 'n': n, 'last': last}, transactional=False)
except taskqueue.TombstonedTaskError:
logging.warn('added a task which is already run, url: %s, block_num: %d' %(url, n))
# added a task with that exact name before which is already run
# executed task names are kept around for some time to prevent accidental duplicates
pass
add_task()
self.response.out.write('添加成功!<br><a href="list">返回</a>')
echo = 'Added tasks into queue: "%s" and started downloading, url: %s' %(conf.DOWNLOAD_FILEBLOCK_QUEUE_NAME, url)
logging.info(echo)
