This prevents an early failure of the command execution on the client
when one slave gets back online but is still loading the dataset from
disk (when this happens, Redis returns the -LOADING error response).
This commit fixes#280.
Now the client can discover the whole replication configuration by
asking to one of the servers (master has the precedence) using the
INFO REPLICATION command. This is obviously a best-effort fallback
and there is no strong guarantee about reliability and efficiency.
By enabling auto-discovery, the client automates this process when
the execution of a command fails because one of the target servers
is unreachable. The replication connection requires an instance of
connection factory associated to it in order to be able to create
new connections on the fly.
It is possible to enable the auto-discovery procedure easily via
client options:
$client = new Predis\Client($servers, [
'replication' => true,
'autodiscovery' => true,
]);
Internally the replication class uses this order to pick which server
it should connect to: current connection, one of the slaves, master.
If there is at least 1 slave, connect() will not fail even if master
is undefined. If there are no slaves, connect() will pick master. If
there are no connections registered for replication, connect() will
fail immediatly.
* Renamed SingleConnectionInterface to NodeConnectionInterface since
this name is better and makes even more sense in the context of
cluster and replication scenarios.
* Moved specialized aggregate connections (the ones implementing both
predis and redis cluster and master/slave replication) in a newly
created Predis\Connection\Aggregate sub-namespace.
* Removed the "Connection" part from names of aggregate connection
interfaces in the Predis\Connection\Aggregate sub-namespace.
* Changed "Composable" to "Composite" in the name of interfaces and
classes that can use pluggable protocol processors.
Mark Fettig
Daniele Alessandri