Hi,
I finished work on 'client reconnect' feature (
https://issues.apache.org/jira/browse/IGNITE-901), it is merged into
master. Here is brief description of this feature:
Client node can disconnect from cluster in several cases:
- in case of network problems when client can not re-establish connection
with server
- connection with server was broken for some time, client is able to
re-establish connection with server, but server already dropped client node
since did not receive client heartbeats
- slow clients can be dropped by server (see
TcpCommunicationSpi.slowClientQueueLimit)
Before changes done in ignite-901 in case of disconnection client node was
just stopped.
Now client assigns to a local node new ID and tries to reconnect to
cluster. Note: this has side effect and 'id' property of local ClusterNode
will change in case of client reconnection.
While client tries to reconnect to cluster all Ignite API throws special
exception: IgniteClientDisconnectedException, this exception provides
future which will be completed when client finish reconnect (IgniteCache
API throws CacheException which has IgniteClientDisconnectedException as
its cause).
After client reconnected Ignite API can be used again.
Also we added special discovery events
(EventType.EVT_CLIENT_NODE_DISCONNECTED,
EventType.EVT_CLIENT_NODE_RECONNECTED) and method on IgniteCluster to get
client reconnect future.
New reconnect behavior can be disabled using 'clientReconnectDisabled'
property on TcpDiscoverySpi.
And here is an example how work with disconnected exception looks like:
* IgniteCache cache = ignite.getOrCreateCache(new
CacheConfiguration<>());*
* while (true) {*
* try {*
* cache.put(key, val);*
* }*
* catch (CacheException e) {*
* if (e.getCause() instanceof IgniteClientDisconnectedException)
{*
* IgniteClientDisconnectedException cause =
(IgniteClientDisconnectedException)e.getCause();*
* cause.reconnectFuture().get();*
* // Client reconnected, can proceed and use the same cache
instance.*
* }*
* }*
* }*
