17.2. The Transaction Context
In order for a transaction to span a number of services, certain information has to be shared between those services, to propagate information about the transaction. This information is known as the Context. The coordination service hands a context back to the application client when it begins a transaction. This context is passed as an extra, hidden parameter whenever the client invokes a transactional web service. The XTS implementation saves and propagates this context automatically with only minimal involvement required on the part of the client. However, it is still helpful to understand what information is captured in a context. This information is listed in Contents of a Context.
Contents of a Context
- Transaction Identifier
- Guarantees global uniqueness for an individual transaction.
- Transaction Coordinator Location
- The endpoint address participants contact to enroll.
Figure 17.2. Web Services and Context Flow