Soabase augments the standard Dropwizard HttpClient and Jersey Client with a number of features useful in an SOA environment.
With the REST Client Enhancements, you can call APIs for services and have Service Discovery choose which service instance to use. Simply use the Soabase hostname format for the url passed to the REST client:
http://0.service-name/path/to/api
You can also use the utility ClientUtils.serviceNameToHost(). When the enhanced REST clients see this hostname format, they call SoaDiscovery.getInstance() using the service name and substituting the returned instance's host and port. If the request needs to be retried (due to errors, etc.) a new instance is retrieved and substituted.
In an SOA, multiple services are usually involved in handling an end-user request. For tracking and auditing, it's useful to have a way to correlate all of them to the initiating end-user request. Soabase enables this via the Request ID. Via the SoaClientFilter every incoming request is assigned a unique request ID. Further, the REST client enhancements set a header on outgoing requests with this request ID. The SoaClientFilter looks for this header and uses the request ID from it when found.
To use the enhanced REST clients add the configuration and add the bundle:
Your application's Configuration object must have a SoaClientConfiguration field. See the Configuration page for details.
Add the SoaClientBundle (after adding the SoaBundle).
The SoaClientBundle registers the clients in Jersey's dependency injection system. E.g.
@Path(...)
public class MyResource {
@Inject
public MyResource(Client jerseyClient) {
...
}
}The client can also be accessed from SoaFeatures. E.g.
SoaFeatures features = SoaBundle.getFeatures(environment); Client jerseyClient = features.getNamedRequired(Client.class, clientName);