本文整理汇总了Python中connection.Connection.describe_ring方法的典型用法代码示例。如果您正苦于以下问题：Python Connection.describe_ring方法的具体用法？Python Connection.describe_ring怎么用？Python Connection.describe_ring使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类connection.Connection的用法示例。
在下文中一共展示了Connection.describe_ring方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的Python代码示例。
示例1: SystemManager
# 需要导入模块: from connection import Connection [as 别名]
# 或者: from connection.Connection import describe_ring [as 别名]
class SystemManager(object):
"""
Lets you examine and modify schema definitions as well as get basic
information about the cluster.
This class is mainly designed to be used manually in a python shell,
not as part of a program, although it can be used that way.
All operations which modify a keyspace or column family definition
will block until the cluster reports that all nodes have accepted
the modification.
Example Usage:
.. code-block:: python
>>> from pycassa.system_manager import *
>>> sys = SystemManager('192.168.10.2:9160')
>>> sys.create_keyspace('TestKeyspace', replication_factor=1)
>>> sys.create_column_family('TestKeyspace', 'TestCF', column_type='Standard',
... comparator_type=LONG_TYPE)
>>> sys.alter_column_family('TestKeyspace', 'TestCF', key_cache_size=42, gc_grace_seconds=1000)
>>> sys.drop_keyspace('TestKeyspace')
>>> sys.close()
"""
def __init__(self, server='localhost:9160', credentials=None, framed_transport=True,
timeout=_DEFAULT_TIMEOUT):
self._conn = Connection(None, server, framed_transport, timeout, credentials)
def close(self):
""" Closes the underlying connection """
self._conn.close()
def get_keyspace_column_families(self, keyspace, use_dict_for_col_metadata=False):
"""
Returns a raw description of the keyspace, which is more useful for use
in programs than :meth:`describe_keyspace()`.
If `use_dict_for_col_metadata` is ``True``, the CfDef's column_metadata will
be stored as a dictionary where the keys are column names instead of a list.
Returns a dictionary of the form ``{column_family_name: CfDef}``
"""
if keyspace is None:
keyspace = self._keyspace
ks_def = self._conn.describe_keyspace(keyspace)
cf_defs = dict()
for cf_def in ks_def.cf_defs:
cf_defs[cf_def.name] = cf_def
if use_dict_for_col_metadata:
old_metadata = cf_def.column_metadata
new_metadata = dict()
for datum in old_metadata:
new_metadata[datum.name] = datum
cf_def.column_metadata = new_metadata
return cf_defs
def get_keyspace_description(self, *args, **kwargs):
"""
Alias for :meth:`get_keyspace_column_families()`
.. deprecated:: 1.0.4
Use :meth:`get_keyspace_column_families()`
"""
warnings.warn("SystemManager.get_keyspace_description() is deprecated; " +
"use get_keyspace_column_families instead.", DeprecationWarning)
return self.get_keyspace_column_families(*args, **kwargs)
def get_keyspace_properties(self, keyspace):
"""
Gets a keyspace's properties.
Returns a :class:`dict` with 'replication_factor', 'strategy_class',
and 'strategy_options' as keys.
"""
if keyspace is None:
keyspace = self._keyspace
ks_def = self._conn.describe_keyspace(keyspace)
return {'replication_factor': ks_def.replication_factor,
'replication_strategy': ks_def.strategy_class,
'strategy_options': ks_def.strategy_options}
def list_keyspaces(self):
""" Returns a list of all keyspace names. """
return [ks.name for ks in self._conn.describe_keyspaces()]
def describe_ring(self, keyspace):
""" Describes the Cassandra cluster """
return self._conn.describe_ring(keyspace)
def describe_cluster_name(self):
""" Gives the cluster name """
return self._conn.describe_cluster_name()
#.........这里部分代码省略.........
示例2: SystemManager
# 需要导入模块: from connection import Connection [as 别名]
# 或者: from connection.Connection import describe_ring [as 别名]
#.........这里部分代码省略.........
if cfdef.row_cache_save_period_in_seconds == 0:
s = 'Disabled'
else:
s = str(cfdef.row_cache_save_period_in_seconds) + ' seconds'
print " Row Cache:", spaces, s
spaces = " " * (35 - len(' Key Cache:'))
if cfdef.key_cache_save_period_in_seconds == 0:
s = 'Disabled'
else:
s = str(cfdef.key_cache_save_period_in_seconds) + ' seconds'
print " Key Cache:", spaces, s
print
if cfdef.column_metadata:
print "Column Metadata"
for coldef in cfdef.column_metadata:
spaces = " " * (35 - len(' - Name:'))
print " - Name:", spaces, coldef.name
spaces = " " * (35 - len(' Value Type:'))
s = coldef.validation_class
print " Value Type:", spaces, s[s.rfind('.') + 1: ]
if coldef.index_type is not None:
spaces = " " * (35 - len(' Index Type:'))
s = IndexType._VALUES_TO_NAMES[coldef.index_type]
print " Index Type:", spaces, s[s.rfind('.') + 1: ]
spaces = " " * (35 - len(' Index Name:'))
print " Index Name:", spaces, coldef.index_name
print
def describe_ring(self, keyspace):
""" Describes the Cassandra cluster """
return self._conn.describe_ring(keyspace)
def describe_cluster_name(self):
""" Gives the cluster name """
return self._conn.describe_cluster_name()
def describe_version(self):
""" Gives the server's API version """
return self._conn.describe_version()
def _system_add_keyspace(self, ksdef):
schema_version = self._conn.system_add_keyspace(ksdef)
self._wait_for_agreement()
return schema_version
def _system_update_keyspace(self, ksdef):
schema_version = self._conn.system_update_keyspace(ksdef)
self._wait_for_agreement()
return schema_version
def create_keyspace(self, name, replication_factor,
replication_strategy=SIMPLE_STRATEGY,
strategy_options=None):
"""
Creates a new keyspace. Column families may be added to this keyspace
after it is created using :meth:`create_column_family()`.
`replication_strategy` determines how replicas are chosen for this keyspace.
The strategies that Cassandra provides by default
are available as :const:`SIMPLE_STRATEGY`, :const:`NETWORK_TOPOLOGY_STRATEGY`,