Universal Linker - 1.7

Extension ID

com.castsoftware.wbslinker

What's new?

See Universal Linker - 1.7 - Release Notes.

Description

The "Universal Linker" (com.castsoftware.wbslinker) extension is a "dependent" extension that automatically creates links for "web services" between client and server components by following a particular protocol based on objects and names. The extension can be downloaded on its own as a standalone extension, however, it is usually automatically downloaded as a dependency with other extensions.

For example for the AngularJS extension:

What does it do?

The Universal Linker automatically creates cross-technology call links between client (front end) and server (back end) objects. For example, AngularJS front end connected to JEE/Spring MVC back end:

CAST Imaging Viewer

The information generated by the extension is also used in CAST Imaging Viewer for the "Application to Application dependencies scope" - see the section "Where do the links come from"

How does it do it?

The Universal Linker supports several communication modes:

• HTTP Call
  • REST services
  • WSDL/SOAP services
  • Cloud Functions
    • AWS Lambda
  • Intra-layers
    • Bean
    • Servlet
• Messaging Call
  • RabbitMQ
  • ActiveMQ
  • IBM MQ
  • gRPC
  • AWS SQS
• Program Call
  • Shell script
  • Cobol Program
  • Java Application 

Note that errors and warnings that may potentially be returned during an analysis are as follows:

HTTP Call

REST services

The connection is made via the following "root" objects:

The Universal Linker searches for objects stored in the CAST Analysis Service schema whose type inherits from CAST_ResourceService or CAST_WebServiceLinker_Resource. These objects represent queries to web services on the client side. Then it searches for the web services on the server side: these are objects whose type inherits from CAST_WebService_Operation or CAST_WebServiceLinker_Operation.

When a match is found using the properties CAST_ResourceService.uri / CAST_WebServiceLinker_Resource.uri and CAST_WebService_Operation.identification.name / CAST_WebServiceLinker_Operation.identification.name and type of both objects, then a link is created. The matching is done between using the properties CAST_ResourceService.uri / CAST_WebServiceLinker_Resource.uri and CAST_WebService_Operation.identification.name / CAST_WebServiceLinker_Operation.identification.name.

Before matching, the Universals Linker transforms the CAST_ResourceService.uri using following rules, in this order:

• It replace all "//" with "/{}/" except "//" after ":" (to avoid replacing "http://"), supposing that a parameter was intended between both "/" (REST format).
• It removes everything after "?" in the uri (to suppress uri parameters part which are not part of REST format parameters).
• It adds a "/" at the end of uri when not present

 The result is then compared to CAST_WebService_Operation.identification.name / CAST_WebServiceLinker_Operation.identification.name using the endswith function, ignoring the uri part corresponding to the operation name part whose value is {}.

Examples of matches:

A client side url like:

• "https://maps.yahoo.com/place//?addr=Meudon%2C%20Ile-de-France%2C%20France"

is transformed as:

• "https://maps.yahoo.com/place/{}/".

It will match a server side operation whose name is "place/{}/".

Code examples

Server side: the Analysis Service schema contains an object CAST_WebService_GetOperation named /users/

@RequestMapping("/users")
public class UserController {
    
    @RequestMapping(method = RequestMethod.GET, produces = "application/json; charset=utf-8")
    @ResponseBody
    public PagedResources<UserResource> collectionList(...){
	   ...
    }

Client side: the Analysis Service schema contains an object CAST_AngularJS_GetResourceService whose property CAST_ResourceService.uri equals 'resources/scenarios/{}/'

return $resource('resources/scenarios/:id', {'id':'@id'}, {
	'query': { method: 'GET', isArray: false },
	'save': {method:'POST', isArray: false },
	'update': {method:'PUT', isArray: false },
	'notify': {method:'PUT', params: {notify: true}, isArray: false },
	'remove': {method:'POST', isArray: false, headers:{'X-HTTP-Method-Override':'DELETE'}}

Cloud Functions

See AWS Lambda for more information.

WSDL/SOAP services

The connection is made via two "root" objects:

WSDL is generally used in the context of SOAP web services: calls are to an operation, and operations are identified by :

• operation name
• port type

Samples:

Client side: BPEL: Invocation of EmployeeTravelStatusPT.EmployeeTravelStatus:

<invoke partnerLink="employeeTravelStatus" 
	portType="emp:EmployeeTravelStatusPT" 
	operation="EmployeeTravelStatus"
	inputVariable="EmployeeTravelStatusRequest" 
	outputVariable="EmployeeTravelStatusResponse" />

Server side: JAX-WS: Reception of operation EmployeeTravelStatusPT.EmployeeTravelStatus:

import javax.jws.WebService;

@WebService(targetNamespace = "http://superbiz.org/wsdl")
public class EmployeeTravelStatusPT {

    public int EmployeeTravelStatus(int add1, int add2)
    {
        
    }
}

BPEL: Reception of operation TravelApprovalPT.TravelApproval:

<receive partnerLink="client" 
	portType="trv:TravelApprovalPT" 
	operation="TravelApproval" 
	variable="TravelRequest"
	createInstance="yes" />

REST/SOAP Cross-Technology

Messaging

The connection is made via two "root" objects:

For the following technologies see the documentation for com.castsoftware.mqe:

• RabbitMQ
• ActiveMQ
• IBM MQ

For the following technology see the documentation for AWS SNS support:

• AWS SNS

For the following technology see the documentation for AWS SQS support:

• AWS SQS

For the following technology see the documentation for gRPC-java:

• gRPC

Direct Web Remoting - Function Call

The connection is made via two "root" objects:

For more details about DWR technology see the documentation for com.castsoftware.dwr.

Program Call

The connection is made via two "root" objects:

For the following technologies see the documentation for com.castsoftware.java2program:

• Shell script
• Cobol Program
• Java Application

Commands running SQL script

The connection is made via two "root" objects: 

See also the documentation for com.castsoftware.rpg.