Webmethods Business Process Management (BPM)- Call Activity

In this tutorial we will discuss how to use the call activity in your business process. We will cover the following points:

  1. Difference between ‘Call-Activity’, and ‘Sub-process’.
  2. Example using the ‘Call Activity’.

 

Note: This tutorial is valid for webMethods versions 8.X to 9.X. You need to be familiar with webMethods business process familiar. 

If you are not familiar with developing a business process with webMethods, please read the article on the following link:

webMethods Business Process Management (BPM) – Getting started

1. Difference between ‘Call-Activity’, and ‘Sub-process’.

Call Activity: it a step in a business process which invoke an existing ‘callable’ business process model. The business process which uses the call activity is called ‘Parent process’, and the called process is called ‘Child process’.

‘Sub-process’: is a block/group of steps in the business process, it is used to make reading the model easier, or repeat the sub-process in a loop.

So the difference is that the ‘Call activity’ can be used in more than one model to perform a specific functionality, but ‘Sub-process’ is used inside one business process, and it can’t be used in another model because it is simply a group of steps in a model.

2. Example using ‘Call Activity’

objective: develop a business process for a bank to issue a new credit card. The process will:

  • Validate if the customer already exists in the bank system or not.
  • If the customer doesn’t have an account, the process will call another business process ‘createCustomer’ to create the user profile. The ‘CreateCustomer’ process should be available for future use by another business process.
  • The business process will send the order to issue the credit card and send it to client.

So we are going to develop two business models:

  1. Create Customer (callable business process/ child business process),
  2. Credit card request (the parent business process)

Note: We will discuss the details related to creating the callable business process, and using the call activity. We will not discuss the details of the regular steps as we already explained it in our earlier tutorials.

1. ‘CreateCustomer’ business process

This process should be callable business process and it should follow the specification of BPMN 2.0 (Business Process Model and Notation) as the use webMethods business process is deprecated (we will discuss the BPMN 2.0 specification in future tutorials).

Here is the process model:

CallAct- create Customer Model

The differences between this process model and any other regular business process(webMethods business processes) are in the start, end step, and configuring the ‘Global Process Specifications’.

The process must start with a ‘non-start event’ step (the empty green circle), and it must ends with the ‘End’ step (the empty red circle).

call activityin the palette

The start, and End steps are for marking the starting point, and end point of the model only, that’s why there is no input or output document in the implementation tab.

non start event property

The remaining steps are:

‘validateData’: is a service task to make sure that all the requires fields are present.

‘CreateCustomer’: is a service task responsible in creating the customer in the bank system, and it is called only if the validation result is ‘true’ (Valid=true).

‘PrepareOutputDoc’: is a service task which is responsible to map/construct the final output document which will be passed to parent/caller model. The join type on this step  ‘Un-Synchronized OR ’ which means it will be executed if only one of the conditions was true (Valid= true, or valid != true).

The last and important step is configuring the ‘Global Process Specifications’. Click anywhere outside of the process pool of the process and you will find the business process properties in the property tab, choose the ‘Global Process Specifications’ as per the below image.

createCustomer - global process specification

Add the document type of the input and output in the ‘Input/output specification for callable process’. This step is important for the following reasons:

a) The process engine will search for the output document type in the pipeline while terminating the process instance in the runtime to be returned to the parent/caller business process.

b) For the caller/parent business process the callable business process is like a service call and its input/output parameters are the parameters defined in the ‘Global Process Specifications’.

This model is ready, please deploy it to be able to use/call it from the parent business process in the next section.

2. ‘CreditCardRequest’ process

Which is responsible for checking if the customer is an existing customer or not. If it found that it is a new customer the process will call the callable business process ‘CreateCustomer, then it issues the credit card for the customer.

Credit card request

The process is a regular business process following the rules we discussed in our earlier tutorials. The new is the use of the call activity to call another business process ‘CreateCustomer’ as a step in the business process. From the palette choose the ‘Call Activity’.

call activityin the palette

Click on the call activity step in your model to configure the business process to be called in the ‘properties > Implementation’ tab.

call activity properties

We will choose the type ‘BPMN callable process’, and we will press the ‘…’ button to choose the business process.

Note: You have to compile/deploy the callable business process (createCustomer)to be able to choose it.

If you go to the inputs/outputs parameters of the ‘Call activity’ step you will find the parameters of the callable business process which were defined in the ‘Process Global Specifications’.

Please deploy the process after finishing the development of the other steps (validation service, choosing the subscription document for the parent process, …)

Note: In the run time you will find one instance for the parent model(CreditCardRequest), and another one for the child model (createCustomer) in myWebmethods.

We hope that you find what you are looking for in our tutorial, and we are looking forward reading your comments and questions.

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(C) 2015 Hossam Elsharkawy. All rights reserved.

Webmethods BPM: Using Correlation Tutorial- Part 2

We discussed in the last tutorial how we can design a business process waiting for external response or event using the correlation, and we mentioned that there are three ways to implement correlation using web methods BPM 1)Field, 2)correlation service, and 3) manual. We covered implementing the correlation by Field in our last tutorial. Today we are going to cover the service correlation.

It is strongly recommended to read the first part of the tutorial before reading this one.

Here is the link for part 1:

https://webmethodsexpert.com/2014/09/21/webmethods-bpm-using-correlation-tutorial-part-1/

 

Note: This tutorial is valid for web methods versions 8, and 9.

We will use the same example of part 1:

Description of the process:

We will assume that we are designing a process to perform credit check for a bank before accepting a loan request. We will send the request to the credit office and our process will be waiting for the asynchronous response from the credit office. After receiving the response we will notify the customer by email.

Here is the subscription document we will use to start the model:

Field name Description
LoanRequest The subscription document name (publishable document)
LoanRequest/requestNumber The unique id of the customer request
LoanRequest/socialInsuranceNumber the social insurance number of the customer (unique government number for each person)
LoanRequest/lastName the last name of the customer
LoanRequest/firstName the first name of the customer
LoanRequest/dateOfBirth the date of birth of the customer
LoanRequest/postalCode the postal code of the customer
LoanRequest/telephoneNumber the phone number of the customer
LoanRequest/email the email of the customer, which will be used to inform the customer of the result of the request.

 

Here is the process model we designed:

bp main

 

To configure the business process model to use the correlation, please follow the following steps:

1. Choose the subscription document which will start the model, by clicking on the receive step (NewLoanRequest in our example), go the properties tab –> Implementation, and choose the receive Document (in our example ‘LoanRequest’).

subscription step document

 

 

2. For the receive step move from the implementation to Correlation tab, then choose ‘service’ and choose the name of the service which will generate the correlation id. In our example the service name is ‘CreateLoadCorrelationId’.

This service is responsible only for constructing the correlationId.

Our correlationId will be the ‘loan request number’ followed by the ‘social insurance number’. So assuming that the loan request number is ‘9999’ and the social insurance number is ‘123123123’, then the correlation id will be ‘9999123123123’.

The input parameters of the service which will generate the correlation is the ‘loanRequest’ document, and the output of the correlation service must be ‘processCorrelationID’

 

createCorrId_constructID

 

 

we assume that we expose a web service to receive the response and then we will publish the document ‘CreditCheckResult’ to continue the processing of the model.

 

3. Assign a flow service to the step SendCreditCheck which will call the credit office web service to send the request, and we will receive the response asynchronously.

4. Configure the joint of the step ‘CheckResponse’ as ‘And’, to make sure that the model will be stored in the database without using any Integration server resources in a waiting state till receiving the response of the intermediate receive step ‘ReceiveCreditOfficeResponse’.

5. Define your response document ‘CreditCheckResult’ as follows:

Name Description
CreditCheckResult The publishable response document
CreditCheckResult/requestNumber Is a unique id for the customer request
CreditCheckResult/socialInsuranceNumber the social insurance number of the client.
CreditCheckResult/creditScore the credit score of the customer.
CreditCheckResult/isBlackListed flag is indicate if the customer is blacklisted or not.
CreditCheckResult/rating Customer rating (high profile, low profile, … etc)

 

6. Configure the intermediate receive step ‘ReceiveCreditOfficeResponse’ from the properties tab –> implementation –> Receive document.

7. Move form implementation to correlation tab, choose radio button‘service’, and choose the correlation service (in our example: getResponseCorrelationId)

getResponseCorrelationId

8. The input parameter of our correlation service is ‘creditCheckResult’, and of course the output must be ‘processCorrelationID’.

    9. Assign a flow service to the step ‘NotifyCustomer’, which will send an email to the customer with the request result.

 

Now your model is ready for the deployment and testing.

So finally we use the service correlation if the correlation value is complex and is not present in the subscription or intermediate receive step, and you will have to construct it based on some calculation or by checking it in another system.

We hope that you enjoyed the tutorial, and looking forwards reading your comments, and questions.

 

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(C) 2014 Hossam Elsharkawy. All rights reserved.