Merged new sentinel commands from #834 (#1550)

* Merged new sentinel commands from #835

Thanks you @otherpirate for the contribution!

* Added an execute wrapper and tests.

The tests ensure that the function is called. Nothing more since we do not currently have enough testing support for sentinel

redis/client.py

@@ -675,10 +675,14 @@ class Redis(Commands, object):
         'SCRIPT FLUSH': bool_ok,
         'SCRIPT KILL': bool_ok,
         'SCRIPT LOAD': str_if_bytes,
+        'SENTINEL CKQUORUM': bool_ok,
+        'SENTINEL FAILOVER': bool_ok,
+        'SENTINEL FLUSHCONFIG': bool_ok,
         'SENTINEL GET-MASTER-ADDR-BY-NAME': parse_sentinel_get_master,
         'SENTINEL MASTER': parse_sentinel_master,
         'SENTINEL MASTERS': parse_sentinel_masters,
         'SENTINEL MONITOR': bool_ok,
+        'SENTINEL RESET': bool_ok,
         'SENTINEL REMOVE': bool_ok,
         'SENTINEL SENTINELS': parse_sentinel_slaves_and_sentinels,
         'SENTINEL SET': bool_ok,

redis/commands.py

@@ -2950,7 +2950,7 @@ def execute(self):
         return self.client.execute_command(*command)
 
 
-class SentinalCommands:
+class SentinelCommands:
     """
     A class containing the commands specific to redis sentinal. This class is
     to be used as a mixin.
@@ -2993,3 +2993,54 @@ def sentinel_set(self, name, option, value):
     def sentinel_slaves(self, service_name):
         "Returns a list of slaves for ``service_name``"
         return self.execute_command('SENTINEL SLAVES', service_name)
+
+    def sentinel_reset(self, pattern):
+        """
+        This command will reset all the masters with matching name.
+        The pattern argument is a glob-style pattern.
+
+        The reset process clears any previous state in a master (including a
+        failover in progress), and removes every slave and sentinel already
+        discovered and associated with the master.
+        """
+        return self.execute_command('SENTINEL RESET', pattern, once=True)
+
+    def sentinel_failover(self, new_master_name):
+        """
+        Force a failover as if the master was not reachable, and without
+        asking for agreement to other Sentinels (however a new version of the
+        configuration will be published so that the other Sentinels will
+        update their configurations).
+        """
+        return self.execute_command('SENTINEL FAILOVER', new_master_name)
+
+    def sentinel_ckquorum(self, new_master_name):
+        """
+        Check if the current Sentinel configuration is able to reach the
+        quorum needed to failover a master, and the majority needed to
+        authorize the failover.
+
+        This command should be used in monitoring systems to check if a
+        Sentinel deployment is ok.
+        """
+        return self.execute_command('SENTINEL CKQUORUM',
+                                    new_master_name,
+                                    once=True)
+
+    def sentinel_flushconfig(self):
+        """
+        Force Sentinel to rewrite its configuration on disk, including the
+        current Sentinel state.
+
+        Normally Sentinel rewrites the configuration every time something
+        changes in its state (in the context of the subset of the state which
+        is persisted on disk across restart).
+        However sometimes it is possible that the configuration file is lost
+        because of operation errors, disk failures, package upgrade scripts or
+        configuration managers. In those cases a way to to force Sentinel to
+        rewrite the configuration file is handy.
+
+        This command works even if the previous configuration file is
+        completely missing.
+        """
+        return self.execute_command('SENTINEL FLUSHCONFIG')

redis/sentinel.py

@@ -2,7 +2,7 @@
 import weakref
 
 from redis.client import Redis
-from redis.commands import SentinalCommands
+from redis.commands import SentinelCommands
 from redis.connection import ConnectionPool, Connection
 from redis.exceptions import (ConnectionError, ResponseError, ReadOnlyError,
                               TimeoutError)
@@ -133,7 +133,7 @@ def rotate_slaves(self):
         raise SlaveNotFoundError('No slave found for %r' % (self.service_name))
 
 
-class Sentinel(SentinalCommands, object):
+class Sentinel(SentinelCommands, object):
     """
     Redis Sentinel cluster client
 
@@ -179,6 +179,23 @@ def __init__(self, sentinels, min_other_sentinels=0, sentinel_kwargs=None,
         self.min_other_sentinels = min_other_sentinels
         self.connection_kwargs = connection_kwargs
 
+    def execute_command(self, *args, **kwargs):
+        """
+        Execute Sentinel command in sentinel nodes.
+        once - If set to True, then execute the resulting command on a single
+               node at random, rather than across the entire sentinel cluster.
+        """
+        once = bool(kwargs.get('once', False))
+        if 'once' in kwargs.keys():
+            kwargs.pop('once')
+
+        if once:
+            for sentinel in self.sentinels:
+                sentinel.execute_command(*args, **kwargs)
+        else:
+            random.choice(self.sentinels).execute_command(*args, **kwargs)
+        return True
+
     def __repr__(self):
         sentinel_addresses = []
         for sentinel in self.sentinels:

tests/test_sentinel.py

@@ -30,9 +30,15 @@ def sentinel_slaves(self, master_name):
             return []
         return self.cluster.slaves
 
+    def execute_command(self, *args, **kwargs):
+        # wrapper  purely to validate the calls don't explode
+        from redis.client import bool_ok
+        return bool_ok
+
 
 class SentinelTestCluster:
-    def __init__(self, service_name='mymaster', ip='127.0.0.1', port=6379):
+    def __init__(self, servisentinel_ce_name='mymaster', ip='127.0.0.1',
+                 port=6379):
         self.clients = {}
         self.master = {
             'ip': ip,
@@ -42,7 +48,7 @@ def __init__(self, service_name='mymaster', ip='127.0.0.1', port=6379):
             'is_odown': False,
             'num-other-sentinels': 0,
         }
-        self.service_name = service_name
+        self.service_name = servisentinel_ce_name
         self.slaves = []
         self.nodes_down = set()
         self.nodes_timeout = set()
@@ -198,3 +204,16 @@ def test_slave_round_robin(cluster, sentinel, master_ip):
     assert next(rotator) == (master_ip, 6379)
     with pytest.raises(SlaveNotFoundError):
         next(rotator)
+
+
+def test_ckquorum(cluster, sentinel):
+    assert sentinel.sentinel_ckquorum("mymaster")
+
+
+def test_flushconfig(cluster, sentinel):
+    assert sentinel.sentinel_flushconfig()
+
+
+def test_reset(cluster, sentinel):
+    cluster.master['is_odown'] = True
+    assert sentinel.sentinel_reset('mymaster')