...

Introduction

The interceptors allow for project-specific extensions of the yuuvis® Momentum standard process flows. The running process flow can be intervened in redirected by a condition set on the processed object , that has to be specified in the interceptor definition. Whenever the process flow satisfies meets the condition, the project-specific process extension is included for the currently processed object at this position of the process flow. Thus, the alternative process can entirely replace the standard one from this position completely on or resume the standard process at a specified position.

...

The condition for the intervention of the process flow is defined in the interceptor configuration file \system\interceptorConfiguration.json.

Parameters

The following parameters can/have to  be defined in are available for the interceptor configuration:

Interceptor Types

There are different types of interceptors available , that interrupt the process flow at different positions.

Configuration Examples

The interceptor configuration is part of the interceptorConfiguration.json file. It is a JSON list of all interceptors, each of them specified by its type, predicate, url and useDirectory parameters. If there are two or more interceptors of the same type, all of them will be executed in random order.

The following two code examples show the configuration of a getContent interceptor. In the first case, the predicate contains the condition in JavaScript. In contrast, the second code example makes use of SpEL.

{
  "interceptors" : [
    { "type" : "getContent",
      "predicate" : "js:function process(dmsApiObject){return dmsApiObject[\"contentStreams\"][0][\"range\"]!=null && dmsApiObject[\"contentStreams\"][0][\"range\"].startsWith(\"page:\")}",
      "url" : "http://<server>:<port>/api/dms/objects/{system:objectId}",
      "useDiscovery" : false     
    }
  ]
}

{
  "interceptors" : [
    { "type" : "getContent",
      "predicate" : "spel:contentStreams[0]['range'] != null ? contentStreams[0]['range'] matches '(?i)^page:.*' : false",
      "url" : "http://<server>:<port>/api/dms/objects/{system:objectId}",
      "useDiscovery" : false     
    }
  ]
}

...

Interceptor Configuration Example

The following example configures an interceptor that will be trigger by every update of a content (action code 301). At the take-off point after the REPOSITORY service, the enriched request body is passed to the external endpoint specified by url.

To activate this configuration, the REPOSITORY service needs to be restarted. 

{
  	"interceptors" : [
    		{
			"type" : "searchdms.request.objects.upsert.database-before",
      			"predicate" : "spel:!grantedAuthorities.contains('ACCESS_FOREIGN_JOURNAL_OBJECTS')",
      options['action']==301",
			"url" : "http://<server>:<port>exampleinterceptorcontentupdate/api/searchdms/objects/dslupsert",
      			"useDiscovery" : falsetrue
   		}
	]
}


]
}

Summary

This article gave an overview of the interceptor handling interceptors in yuuvis® Momentum. If you want to extend the functionality of your system, also system hooks also might be an interesting topic for you.

...

...

...

...

...