XOM deployment with decision services

When you work with decision services, XOM management ensures that any RuleApp that you deploy to Rule Execution Server references the correct XOM.

With XOM management, when you deploy a RuleApp to Rule Execution Server, Rule Designer goes through the following process:

  1. Builds the XOM binary from the source files that are referenced by the decision service.
  2. Deploys the XOM if it is not already present in Rule Execution Server, and retrieves the XOM URI.
  3. Copies this URI to each ruleset that is contained in the RuleApp. Specifically, Rule Designer copies the URI to a property of the ruleset called ruleset.managedxom.uris. (See Managed Java XOM.)

With this mechanism, each ruleset in Rule Execution Server references the correct XOM.

XOM deployment in Decision Center

RuleApps that you deploy to Rule Execution Server from Decision Center reference the correct XOM in one of two ways. In Rule Designer, you select the option Enable XOM management in Decision Center. This option is in the properties of the main decision service project, under Decision Service. This option has the following effect:

Enabled
When Rule Designer builds the XOM from the source files, it places the XOM binary under resources/xom-libraries. You can then publish the XOM binary to Decision Center.
Note: If you create the resources/xom-libraries/additional-libs folder, files in additional-libs can be published to Decision Center but are not included during RuleApp deployment. These files are typically used to provide custom scenario providers for testing and simulation.
Not enabled
When Rule Designer requests the URI of the XOM from Rule Execution Server, it copies the URI to a deployment.xml file in the resources of the decision service. You can then publish the file to Decision Center.

With the XOM binary or deployment.xml file synchronized between Rule Designer and Decision Center, RuleApps deployed from either environment reference the correct XOM.

Modifying the XOM

You modify the XOM source files in Rule Designer. Rule Designer always builds the XOM binary from the source files. When you import a decision service from Decision Center into an empty workspace:
  • You do not obtain the XOM source files. You must obtain these source files in the usual way, for example through source code control.
  • The XOM binary obtained from Decision Center is copied to the resources/xom-libraries folder. The files in this folder are meant to be synchronized only and they should not be used in the XOM path.