When you need to break up a composite message into smaller parts, but provide access to any of the parts on demand, use a Claim Check. Consider the Claim Check a unique identifier used to store and access a checked item. You pass as part of a processing message the identity of the specific checked …
At this point we’ve covered a number of Message Routers in addition to some less complex, but essential, messaging patterns. With regard to my discussion of Request-Response, Ramesh Mandaleeka asked a few questions about Actor Model and message delivery. One of his questions was “How [do you] handle message sequencing?”
We’ve actually already stepped through one implementation of Scatter-Gather. This was the combination of Recipient List and Aggregator, which provides the first of two Scatter-Gather variants. The second variant—that of using a Publish-Subscribe Channel to send RequestPriceQuote messages to interested participants—is discussed here.
The Recipient List example didn’t demonstrate how the PriceQuote replies are assimilated by the MountaineeringSuppliesOrderProcessor. To correlate PriceQuote replies to the original RequestForQuotation we need to use the unique rfqId that has been passed along with each message:
We’ve looked at a few different kinds of Content-Based Routers, and Recipient List is yet another. A Recipient List is compared to the To: and Cc: fields in an email message, where you specify any number of intended recipients of the email message. Thus, a Recipient List may be predetermined depending on the kind of …
Use a Routing Slip when a large business procedure logically does one thing but physically requires a series of processing steps. This achieves a service composition commonly recognized as SOA. In our Routing Slip process, each step is handled by an individual Actor. The process of this example is customer registration, as described by [Hohpe …
You may have become a bit bored with the previously discussed routing patterns, Splitter and Content-Based Router. It’s not that they aren’t necessary or useful. They absolutely are. But they are also sort of simple and much like each other, with only slight differences in the way they route messages. Sure, in an actual project …
As noted in my discussion on Splitter, a Content-Based Router has a different motivation. While both of these router types are designed to route a message based on message content, the Content-Based Router doesn’t break up the composite parts of one message into multiple messages as does a Splitter. Rather, it routes the whole message …
EAI Patterns with Actor Model: Content-Based Router Read More »
There are various ways to route messages, including Content-Based Router, Dynamic Router, Recipient List, Splitter, Aggregator, Scatter-Gather, Routing Slip, and Process Manager. In time we will take a look at each of these. For now let’s discuss Splitter.
