Polling TCP client connector
Right now TCP inbound endpoints are implemented as TCP servers that listen for data coming from different clients. In Mule ESB 2.2.6 we are adding a new feature to inverse the control: TCP inbounds can now poll data from remote servers.
It is really easy to switch to this strategy. Let’s take a look of how a mule configuration looks like:
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 | <?xml version="1.0" encoding="UTF-8"?> <mule xmlns="http://www.mulesource.org/schema/mule/core/2.2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tcp="http://www.mulesource.org/schema/mule/tcp/2.2" xmlns:vm="http://www.mulesource.org/schema/mule/vm/2.2" xsi:schemaLocation=" http://www.mulesource.org/schema/mule/core/2.2 http://www.mulesource.org/schema/mule/core/2.2/mule.xsd http://www.mulesource.org/schema/mule/vm/2.2 http://www.mulesource.org/schema/mule/vm/2.2/mule-vm.xsd http://www.mulesource.org/schema/mule/tcp/2.2 http://www.mulesource.org/schema/mule/tcp/2.2/mule-tcp.xsd"> <vm:connector name="queue" queueEvents="true" /> <tcp:polling-connector name="pollingConnector" clientSoTimeout="3000" pollingFrequency="1000"> <tcp:direct-protocol payloadOnly="true" /> </tcp:polling-connector> <model name="echoModel"> <service name="echo"> <inbound> <tcp:inbound-endpoint host="localhost" port="4444" /> </inbound> <outbound> <pass-through-router> <vm:outbound-endpoint path="out" connector-ref="queue" /> </pass-through-router> </outbound> </service> </model> </mule> |
Notice the new tcp:polling-connector element in the mule configuration file. This element tells mule to poll data with a frequency of 1000ms and a timeout of 3000ms.
Using the above configuration we can create a TCP server that writes messages like this:
1 2 3 4 5 6 7 | String stringMessage = "the message"; ServerSocket serverSocket = new ServerSocket(4444); Socket clientSocket = serverSocket.accept(); PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true); out.print(stringMessage); out.close(); clientSocket.close(); |
You can check the value received in the out outbound using the MuleClient like this:
1 2 3 | MuleClient client = new MuleClient(); MuleMessage message = client.request("vm://out?connector=queue", 10000); String receivedMessage = message.getPayloadAsString(); |
The receivedMessage variable will hold the received value from the TCP Server.
If you want to try it, please download Mule ESB 2.2.6 or the latest 3.0 milestone
Ratan Mishra
May 26th 2011
Hi Esteban ,
How can i design the service to send the response in a TCP IP client call..
Please give some sample code.