Django object cache with memcache after pickling

Question

I was trying to cache a Django model Instance like

class MyModel(models.Model):
   ...
   several atributes, as well as foreign key attributes
   ...

from pymemcache.client import base
import pickle
obj = MyModel.objects.first()
client = base.Client(("my-cache.pnpnqe.0001.usw2.cache.amazonaws.com", 11211))
client.set("my-key", pickle.dumps(obj), 1000) # 1000 seconds

# and to access I use
obj = pickle.loads(client.get("my-key"))

They both works fine, but sometimes executing the same line:

client.get("my-key")

generates very very strange errors.(different errors like KeyError, OSError) like

Traceback (most recent call last):
  File "/opt/python/current/app/proj/utils/Cache.py", line 93, in get_value
    return Cache.client.get(key, None)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 481, in get
    return self._fetch_cmd(b'get', [key], False).get(key, default)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 823, in _fetch_cmd
    prefixed_keys)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 791, in _extract_value
    key = remapped_keys[key]
KeyError: b'some-other-cache-key'

and sometimes I get:

Traceback (most recent call last):
  File "/opt/python/current/app/proj/utils/Cache.py", line 93, in get_value
    return Cache.client.get(key, None)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 481, in get
    return self._fetch_cmd(b'get', [key], False).get(key, default)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 833, in _fetch_cmd
    raise MemcacheUnknownError(line[:32])

and sometimes, I get

Traceback (most recent call last):

  File "/opt/python/current/app/proj/utils/Cache.py", line 93, in get_value
    return Cache.client.get(key, None)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 481, in get
    return self._fetch_cmd(b'get', [key], False).get(key, default)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 823, in _fetch_cmd
    prefixed_keys)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 790, in _extract_value
    buf, value = _readvalue(self.sock, buf, int(size))
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 1234, in _readvalue
    buf = _recv(sock, RECV_SIZE)
  File "/opt/python/run/venv/local/lib/python3.6/site-packages/pymemcache/client/base.py", line 1257, in _recv
    return sock.recv(size)
OSError: [Errno 9] Bad file descriptor

I dont want to store the data, is there any fix or any other way of pickling that doesn't create this error.

Django object cache with memcache after pickling

0 Answers0