在 class 中引发和捕获异常
raising and catching exceptions in class
我纠结的代码最初在主class - 并且工作得很好！我把它从书里拿出来用了几次！
我试图更改它，以便它 运行 在它自己的 class "twitter_data" 中。
但是由于某种原因，函数 "handle_twitter_http_error" 不再像以前那样工作了……它不再捕获错误了……！
我很确定它与新的 class 结构有关，到目前为止我对此知之甚少！
代码如下：
import twitter
import sys
import time
from urllib2 import URLError
from httplib import BadStatusLine
import json
from functools import partial
from sys import maxint
from six import string_types
from datetime import datetime
from datetime import timedelta
class twitter_data:
def __init__(self):
self.twitter_api = self.oauth_login()
def oauth_login(self):
CONSUMER_KEY = 'KEY'
CONSUMER_SECRET = 'SECRET'
OAUTH_TOKEN = 'TOKEN'
OAUTH_TOKEN_SECRET = 'TOKEN_SECRET'
auth = twitter.oauth.OAuth(OAUTH_TOKEN,OAUTH_TOKEN_SECRET,CONSUMER_KEY,CONSUMER_SECRET)
twitter_api=twitter.Twitter(auth=auth)
return twitter_api
def handle_twitter_http_error(self,e, wait_period=2, sleep_when_rate_limited=True):
if wait_period > 3600:
print >> sys.stderr, 'Too many retries. Quitting'
raise e
if e.e.code == 401:
print >> sys.stderr, 'Encountered 401 Error (Not Authorized)'
return None
if e.e.code == 404:
print >> sys.stderr, 'Encountered 404 Error (Not Found)'
return None
elif e.e.code == (429,420):
print >> sys.stderr, 'Encountered 429/420 Error (Rate Limit Exceeded)',sleep_when_rate_limited
if sleep_when_rate_limited:
print >> sys.stderr, 'Retrying in 15 minutes'
sys.stderr.flush()
time.sleep(60*15+5)
print >>sys.stderr, 'Awake now and retrying'
return 2
else:
raise e
elif e.e.code == (500,502,503,504):
print >> sys.stderr, 'Encountered %i Error. Retrying in %i seconds' %(e.e.code, wait_period)
time.sleep(wait_period)
wait_period *= 1.5
return wait_period
else:
raise e
def make_twitter_request(self,twitter_api_func,max_errors=10,*args, **kw):
wait_period = 2
error_count =0
while True:
try:
return twitter_api_func(*args, **kw)
except twitter.api.TwitterHTTPError, e:
error_count = 0
wait_period = self.handle_twitter_http_error(e,wait_period)
if wait_period is None:
return
except URLError, e:
error_count +=1
print >> sys.stderr, 'URLError encountered. Continuing.'
if error_count > max_errors:
print >> sys.stderr, 'Too many errors...bailing out.'
raise
except BadStatusLine, e:
error_count +=1
print >> sys.stderr, 'BadStatusLine encountered. Continuing.'
if error_count > max_errors:
print >> sys.stderr, 'Too many consecutive errors...bailing out.'
raise
def get_friends_followers_ids(self, screen_name=None, user_id=None, friends_limit=maxint, followers_limit=maxint):
assert (screen_name != None) != (user_id != None), \
"Must have screen_name or user_id, but not both"
get_friends_ids = partial(self.make_twitter_request, self.twitter_api.friends.ids,
count=5000)
get_followers_ids = partial(self.make_twitter_request, self.twitter_api.followers.ids,
count=5000)
friends_ids, followers_ids = [], []
for twitter_api_func, limit, ids, label in [
[get_friends_ids, friends_limit, friends_ids, "friends"],
[get_followers_ids, followers_limit, followers_ids, "followers"]
]:
if limit == 0: continue
cursor = -1
while cursor != 0:
if screen_name:
response = twitter_api_func(screen_name=screen_name, cursor=cursor)
else:
response = twitter_api_func(user_id=user_id, cursor=cursor)
if response is not None:
ids += response['ids']
cursor = response['next_cursor']
print >> sys.stderr, 'Fetched {0} total {1} ids for {2}'.format(len(ids),
label, (user_id or screen_name))
if len(ids) >= limit or response is None:
break
return friends_ids[:friends_limit], followers_ids[:followers_limit]
然后我用这段代码运行它：
td = twitter_data()
td.get_friends_followers_ids(screen_name = 'Madonna')
这就是我得到的错误：
---------------------------------------------------------------------------
TwitterHTTPError Traceback (most recent call last)
<ipython-input-35-420d4a0a4512> in <module>()
----> 1 td.get_friends_followers_ids(screen_name = 'Madonna')
<ipython-input-29-d4275257b38f> in get_friends_followers_ids(self, screen_name, user_id, friends_limit, followers_limit)
174
175 if screen_name:
--> 176 response = twitter_api_func(screen_name=screen_name, cursor=cursor)
177 else:
178 response = twitter_api_func(user_id=user_id, cursor=cursor)
<ipython-input-29-d4275257b38f> in make_twitter_request(self, twitter_api_func, max_errors, *args, **kw)
68 except twitter.api.TwitterHTTPError, e:
69 error_count = 0
---> 70 wait_period = self.handle_twitter_http_error(e,wait_period)
71 if wait_period is None:
72 return
<ipython-input-29-d4275257b38f> in handle_twitter_http_error(self, e, wait_period, sleep_when_rate_limited)
55 return wait_period
56 else:
---> 57 raise e
58
59
TwitterHTTPError: Twitter sent status 429 for URL: 1.1/followers/ids.json using parameters: (count=5000&cursor=-1&oauth_consumer_key=o92R2ryg511yw6yK0zXwHBk4Z&oauth_nonce=8966871855796102181&oauth_signature_method=HMAC-SHA1&oauth_timestamp=1440000524&oauth_token=3013233011-jzjcfNa4D5m08k1TbWHeekl9h7Yt9Mu9U6jEPqv&oauth_version=1.0&screen_name=Madonna&oauth_signature=z8mD3kbclM5UOXTbB2E1VguSxHU%3D)
details: {"errors":[{"message":"Rate limit exceeded","code":88}]}
感谢大家对此的帮助！
更新：
我做了一个 "print debug" 并要求它 "print e.e.code"，这就是我得到的：
td.get_friends_followers_ids(screen_name='Madonna')
429
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "testdriver.py", line 113, in get_friends_followers_ids
response = twitter_api_func(screen_name=screen_name, cursor=cursor)
File "testdriver.py", line 70, in make_twitter_request
wait_period = self.handle_twitter_http_error(e,wait_period)
File "testdriver.py", line 58, in handle_twitter_http_error
raise e
twitter.api.TwitterHTTPError: Twitter sent status 429 for URL: 1.1/followers/ids.json using parameters: (count=5000&cursor=1507581380542740144&oauth_consumer_key=o92R2ryg511yw6yK0zXwHBk4Z&oauth_nonce=4075478308692875785&oauth_signature_method=HMAC-SHA1&oauth_timestamp=1440078685&oauth_token=3013233011-jzjcfNa4D5m08k1TbWHeekl9h7Yt9Mu9U6jEPqv&oauth_version=1.0&screen_name=Madonna&oauth_signature=zZRpNFAQGR1IWcVSwK0dAFOJMuk%3D)
details: {"errors":[{"message":"Rate limit exceeded","code":88}]}
所以它确实包含e.e.code的信息，但由于某种原因没有捕捉到它！！
我终于明白了：
感谢 Grysik 提出
的想法
e.e.code in (429,420)
解决方案完全有效！谢谢
我纠结的代码最初在主class - 并且工作得很好！我把它从书里拿出来用了几次！ 我试图更改它，以便它 运行 在它自己的 class "twitter_data" 中。 但是由于某种原因，函数 "handle_twitter_http_error" 不再像以前那样工作了……它不再捕获错误了……！ 我很确定它与新的 class 结构有关，到目前为止我对此知之甚少！
代码如下：
import twitter
import sys
import time
from urllib2 import URLError
from httplib import BadStatusLine
import json
from functools import partial
from sys import maxint
from six import string_types
from datetime import datetime
from datetime import timedelta
class twitter_data:
def __init__(self):
self.twitter_api = self.oauth_login()
def oauth_login(self):
CONSUMER_KEY = 'KEY'
CONSUMER_SECRET = 'SECRET'
OAUTH_TOKEN = 'TOKEN'
OAUTH_TOKEN_SECRET = 'TOKEN_SECRET'
auth = twitter.oauth.OAuth(OAUTH_TOKEN,OAUTH_TOKEN_SECRET,CONSUMER_KEY,CONSUMER_SECRET)
twitter_api=twitter.Twitter(auth=auth)
return twitter_api
def handle_twitter_http_error(self,e, wait_period=2, sleep_when_rate_limited=True):
if wait_period > 3600:
print >> sys.stderr, 'Too many retries. Quitting'
raise e
if e.e.code == 401:
print >> sys.stderr, 'Encountered 401 Error (Not Authorized)'
return None
if e.e.code == 404:
print >> sys.stderr, 'Encountered 404 Error (Not Found)'
return None
elif e.e.code == (429,420):
print >> sys.stderr, 'Encountered 429/420 Error (Rate Limit Exceeded)',sleep_when_rate_limited
if sleep_when_rate_limited:
print >> sys.stderr, 'Retrying in 15 minutes'
sys.stderr.flush()
time.sleep(60*15+5)
print >>sys.stderr, 'Awake now and retrying'
return 2
else:
raise e
elif e.e.code == (500,502,503,504):
print >> sys.stderr, 'Encountered %i Error. Retrying in %i seconds' %(e.e.code, wait_period)
time.sleep(wait_period)
wait_period *= 1.5
return wait_period
else:
raise e
def make_twitter_request(self,twitter_api_func,max_errors=10,*args, **kw):
wait_period = 2
error_count =0
while True:
try:
return twitter_api_func(*args, **kw)
except twitter.api.TwitterHTTPError, e:
error_count = 0
wait_period = self.handle_twitter_http_error(e,wait_period)
if wait_period is None:
return
except URLError, e:
error_count +=1
print >> sys.stderr, 'URLError encountered. Continuing.'
if error_count > max_errors:
print >> sys.stderr, 'Too many errors...bailing out.'
raise
except BadStatusLine, e:
error_count +=1
print >> sys.stderr, 'BadStatusLine encountered. Continuing.'
if error_count > max_errors:
print >> sys.stderr, 'Too many consecutive errors...bailing out.'
raise
def get_friends_followers_ids(self, screen_name=None, user_id=None, friends_limit=maxint, followers_limit=maxint):
assert (screen_name != None) != (user_id != None), \
"Must have screen_name or user_id, but not both"
get_friends_ids = partial(self.make_twitter_request, self.twitter_api.friends.ids,
count=5000)
get_followers_ids = partial(self.make_twitter_request, self.twitter_api.followers.ids,
count=5000)
friends_ids, followers_ids = [], []
for twitter_api_func, limit, ids, label in [
[get_friends_ids, friends_limit, friends_ids, "friends"],
[get_followers_ids, followers_limit, followers_ids, "followers"]
]:
if limit == 0: continue
cursor = -1
while cursor != 0:
if screen_name:
response = twitter_api_func(screen_name=screen_name, cursor=cursor)
else:
response = twitter_api_func(user_id=user_id, cursor=cursor)
if response is not None:
ids += response['ids']
cursor = response['next_cursor']
print >> sys.stderr, 'Fetched {0} total {1} ids for {2}'.format(len(ids),
label, (user_id or screen_name))
if len(ids) >= limit or response is None:
break
return friends_ids[:friends_limit], followers_ids[:followers_limit]
然后我用这段代码运行它：
td = twitter_data()
td.get_friends_followers_ids(screen_name = 'Madonna')
这就是我得到的错误：
---------------------------------------------------------------------------
TwitterHTTPError Traceback (most recent call last)
<ipython-input-35-420d4a0a4512> in <module>()
----> 1 td.get_friends_followers_ids(screen_name = 'Madonna')
<ipython-input-29-d4275257b38f> in get_friends_followers_ids(self, screen_name, user_id, friends_limit, followers_limit)
174
175 if screen_name:
--> 176 response = twitter_api_func(screen_name=screen_name, cursor=cursor)
177 else:
178 response = twitter_api_func(user_id=user_id, cursor=cursor)
<ipython-input-29-d4275257b38f> in make_twitter_request(self, twitter_api_func, max_errors, *args, **kw)
68 except twitter.api.TwitterHTTPError, e:
69 error_count = 0
---> 70 wait_period = self.handle_twitter_http_error(e,wait_period)
71 if wait_period is None:
72 return
<ipython-input-29-d4275257b38f> in handle_twitter_http_error(self, e, wait_period, sleep_when_rate_limited)
55 return wait_period
56 else:
---> 57 raise e
58
59
TwitterHTTPError: Twitter sent status 429 for URL: 1.1/followers/ids.json using parameters: (count=5000&cursor=-1&oauth_consumer_key=o92R2ryg511yw6yK0zXwHBk4Z&oauth_nonce=8966871855796102181&oauth_signature_method=HMAC-SHA1&oauth_timestamp=1440000524&oauth_token=3013233011-jzjcfNa4D5m08k1TbWHeekl9h7Yt9Mu9U6jEPqv&oauth_version=1.0&screen_name=Madonna&oauth_signature=z8mD3kbclM5UOXTbB2E1VguSxHU%3D)
details: {"errors":[{"message":"Rate limit exceeded","code":88}]}
感谢大家对此的帮助！
更新：
我做了一个 "print debug" 并要求它 "print e.e.code"，这就是我得到的：
td.get_friends_followers_ids(screen_name='Madonna')
429
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "testdriver.py", line 113, in get_friends_followers_ids
response = twitter_api_func(screen_name=screen_name, cursor=cursor)
File "testdriver.py", line 70, in make_twitter_request
wait_period = self.handle_twitter_http_error(e,wait_period)
File "testdriver.py", line 58, in handle_twitter_http_error
raise e
twitter.api.TwitterHTTPError: Twitter sent status 429 for URL: 1.1/followers/ids.json using parameters: (count=5000&cursor=1507581380542740144&oauth_consumer_key=o92R2ryg511yw6yK0zXwHBk4Z&oauth_nonce=4075478308692875785&oauth_signature_method=HMAC-SHA1&oauth_timestamp=1440078685&oauth_token=3013233011-jzjcfNa4D5m08k1TbWHeekl9h7Yt9Mu9U6jEPqv&oauth_version=1.0&screen_name=Madonna&oauth_signature=zZRpNFAQGR1IWcVSwK0dAFOJMuk%3D)
details: {"errors":[{"message":"Rate limit exceeded","code":88}]}
所以它确实包含e.e.code的信息，但由于某种原因没有捕捉到它！！
我终于明白了： 感谢 Grysik 提出
的想法e.e.code in (429,420)
解决方案完全有效！谢谢