Question

我正在尝试从python连接到cassandra，我已将cassandra安装为pip install pycassa。当我尝试连接到cassandra时，我收到以下异常

from pycassa.pool import ConnectionPool
pool = ConnectionPool('Keyspace1')

Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python2.7/site-packages/pycassa/pool.py", line 382, in __init__
self.fill()
File "/usr/lib/python2.7/site-packages/pycassa/pool.py", line 442, in fill
conn = self._create_connection()
File "/usr/lib/python2.7/site-packages/pycassa/pool.py", line 431, in _create_connection
(exc.__class__.__name__, exc))
pycassa.pool.AllServersUnavailable: An attempt was made to connect to each of the servers twice, but none of the attempts succeeded. The last failure was TTransportException: Could not connect to localhost:9160

我正在使用python 2.7。有什么问题，我们将不胜感激。

Answer 1

也许尝试指定主机：

pool = ConnectionPool（'Keyspace1'，['server_node_here：9160']）

Answer 2

将Cassandra与python连接的常规方法。

from cassandra.cluster import Cluster  
cluster = Cluster()    #for connecting on localhost  
cluster = Cluster(['192.168.0.1', '192.168.0.2']) #*for connecting on clusters (comment this line, if you are connecting with localhost)*  
session = cluster.connect('testing')

您还可以使用带有Python的模型类进行连接

from cassandra.cqlengine import columns  
from cassandra.cqlengine.models import  Model  
from cassandra.cqlengine.management import sync_table  
from cassandra.cqlengine import connection  
import uuid  
from datetime import datetime  

connection.setup(['127.0.0.1'], "testing")  #testing is the keyspace

有关模型类实现的详细信息，请看：https://github.com/vishal-kr-yadav/NoSQL_Databases

无法连接cassandra与python

2 个答案: