WCF Note10(Message Pattern)

Classic Message Exchange Pattern (MEP):

1. Request/reply
2. One-way
3. Duplex or callbacks

Transformed Pattern : Publish and subscribe

One Way Scenarios:

1. Fire-and-forget

e.g.: Logging

2. Polling

         e.g.: able to make another request to get the previous request status 

3. Duplex 

e.g.: two ways communication,  with call back function, Butbe aware of concurrency issue

Note: Duplex required two ways communication e.g. WSDualHttpBinding

 Code sample: service contract + callback contract 

Server Side: 

Client Side:

Sample: Publisher/Subscriber

Large Message

1. MTOM: reduces the overhead of binary data transfer: ( help with parsing and sizing transfer)
   1. Remove base64 

   2.  <wsHttpBinding>        <binding name="WsHttpMtomBinding" messageEncoding="Mtom" maxReceivedMessageSize="500000"/><readerQuotas maxArrayLength=”500000"/>    </wsHttpBinding>

      
      
2. Streaming (helping reduce memory usage)

   1. <basicHttpBinding><binding name="basicHttpStreaming"transferMode="Streamed"/></basicHttpBinding>

      
      
   2. [OperationContract]

   Stream LoadData()

1. Chunking message into the small piece

Tool:  TcpTrace