Control headers between Cloverleaf and Intelligent Broker
The engine and Intelligent Broker exchange ibmime messages, as specified in the previous sections. There are a few MIME headers, not part headers, in each ibmime message. These have special meaning to the Intelligent Broker server. Therefore, they must be correctly set. Others are set by the Intelligent Broker server and convey special status information and therefore should be examined by the Tcl procedures.
The headers that are expected by Intelligent Broker on an outgoing ibmime request message by a client thread are:
-
IBSite
-
IBThread
-
Content-Type
The headers that are expected by Intelligent Broker on an outgoing ibmime reply message by a server thread are:
-
IBStatus
-
Content-Type
The header set by Intelligent Broker on an incoming ibmime reply message to a client thread is IBStatus
.
There are no headers set by Intelligent Broker on an incoming ibmime request message to a server thread.
Basically, IBSite
and IBThread
headers identify to Intelligent Broker which
client site/thread sends this ibmime request.
Then, Intelligent Broker can look up configured information about this site/thread
and act correctly. On the other hand, IBStatus
represents a status report back to the client thread about the request being sent to
the remote service.
IBStatus
also serves a dual role when a server
thread is sending a reply to a request. It is used as a directive to the Intelligent
Broker server. It determines the type of response that is sent back to the remote
client.