CMMN diagram deployment

In the same way you can deploy a process diagram together with the process definition, it is reasonable to deploy a case diagram together with case definition. There is an important reason to do so now, since it is basic to case management based on CMMN to be able to see the diagram of the notation.

From the technical point of view, the change is very similar to the what is done on the BPMN part. The CmmnDeployer writes an additional field called diagramResourceName. This field is added to the myBatis mappings, statements and table definitions. The mechanisms of loading and saving resource is essentually there. In order to retrieve the diagram for the case, the repository service has been extended. In addition, a GetDeploymentCaseDiagramCmd provides the ability to retrieve the InputStream which is used the REST Api. This has been extended by a /case-definition/{id}/diagram and case-definition/key/{key}/diagram methods in order to access the case diagram.

I expect this feature as essential BEFORE 7.2 final, since CMMN customers are willing to see the diagrams of the new language. The plugin under development would load the image stored together with the case definition.

I would be happy to be able to contribute it. What do you think?