TsgcWebSocketLoadBalancerServer

The component TsgcWebSocketLoadBalancerServer allows to Load Balancing WebSocket and HTTP Protocols. For websockedt protocol allows to distributing messages across a group of servers and distributes clients connections using a random sequence or fewer connections algorithm.

 

The Load Balancer Server, inherits all methods and properties from TsgcWebSocketHTTPServer.

 

Load Balancer Configuration

The Load Balancer server it's a descendant of TsgcWebSocketHTTPServer, so read the documentation about the TsgcWebSocketHTTPServer to know how to configure it.

 

Additionally, the Load Balancer has the property LoadBalancer, which has the following properties:

 

• LoadBalancing: configure here how distribute the connections
  • lbRandom: (default) every time a new client request a new connection, it will return a random server.
  • lbConnections: every time a new client request a new connection, it will return server with fewer clients connected.
• Protocols: configure which protocols are enabled
  • WebSocket: if true, the websocket connections will be handled by the Load Balancer Server.
  • HTTP: if true, the http connections will be handled by the Load Balancer Server.

 

 

Backup Server Configuration

The Backup Servers (the servers behind the load balancer) can be a TsgcWebSocketServer, TsgcWebSocketHTTPServer or a Datasnap Server.

Those servers have a property called LoadBalancer where you can configure the connection between the LoadBalancer Server and the Backup Servers.

 

• Enabled: set to true if you want to use as a backup server.
• Host: the host were is the LoadBalancer.
• Port: the listening port of the LoadBalancer.
• Guid: unique id that identifies this server.
• Bindings: the public addresses accessible were the connections will be forwarded. Example: if the Backup WebSocket server is listening on port 8000 and the ip address is 1.1.1.1, use the following: ws://1.1.1.1:8000;
• AutoRegisterBindings: if enabled, the LoadBalancer Server will use the Bindings property of the backup server to configure the public bindings.
• AutoRestart: in seconds, if greater than zero, the load balancer client of the backup server will enable an internal watchdog that every x seconds, will check if the connection is alive, if it's closed, it will try to reconnect.

 

Events

 

• OnBeforeSendServerBinding: raised before binding is sent to a new client connection.

 

• OnClientConnect: every time a client connection is stablished, this event is triggered.

 

• OnClientDisconnect: every time a client connection is dropped, this event is triggered.

 

• OnClientMessage: raised when a new text message is received from the server.

 

• OnClientBinary: raised when a new binary message is received from the server.

 

• OnClientFragmented: raised when a new fragmented message is received from the server.

 

• OnServerConnect: raised when a new server connects to LoadBalancerServer.

 

• OnServerDisconnect: raised when a server disconnects from LoadBalancerServer.

 

• OnServerReady: raised when a server is ready to accept messages.

 

• OnLoadBalancerHTTPRequest: the event is called when there is a new HTTP Request and before it's forwarded to a backup server.

 

• OnLoadBalancerHTTPResponse: the event is called with the HTTP Response sent by the backup server.