BPMN CAMUNDA part 1 :

BPMN, which stands for Business Process Model and Notation, is a standardized graphical notation used for modeling business processes in a visual way. BPMN diagrams use symbols and shapes to represent different elements such as tasks, events, gateways, and flows, making it easier for user to understand, analyze, and communicate complex business processes.

software/application needs:

Java , Maven ,postman, eclipse , camunda modeler

Camunda Architecture:

Camunda follows a microservices-based architecture for its BPM (Business Process Management) platform. In simple terms, the Camunda architecture can be explained as follows:

1. Camunda Engine:

   • At the core is the Camunda Engine, responsible for executing and managing business processes. It interprets and executes BPMN (Business Process Model and Notation) diagrams.

2. Database:

   • Camunda uses a relational database to store and manage process instances, tasks, and other relevant data.

3. REST API:

   • Camunda provides a REST API that allows external applications to interact with the Camunda Engine. This enables developers to start, complete, or query process instances programmatically.

4. Web Applications:

   • Camunda offers web applications (like Tasklist and Cockpit) for user interaction. Tasklist allows users to view and complete assigned tasks, while Cockpit provides insights and monitoring capabilities for process instances.

5. External Services:

   • External services, which can be other microservices or existing systems, may be integrated into the BPMN diagrams. These services perform specific tasks or provide data to the business processes.

     lets take one basic example: Leave application system , where user enter any leave to application , than he needs first manager approval than HR to leave to be approved.

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   • Start Event: The Start Event marks the initiation or beginning of a business process.

     Service Task: A Service Task is a type of activity in a business process that represents work that is performed by a software service, application, or automated process. It usually doesn't involve human interaction directly.

     User Task:A User Task is an activity in a business process that involves manual or human interaction. It represents work that needs to be performed by a human user.

     End Event: The End Event signifies the conclusion or completion of a business process. It indicates where a process finishes its execution.

     Lets start with coding part:

     Like Spring initializer we have Comunda initializer ,like this ;Click generate project and open it into any ,here I am using Eclipse .

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     now just open your project , build it and run , here it goes yeahhhhh ✌️🤩🤩

   • It started on tomcat 8080 , just like spring boot nothing extras .

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     Now your all setup is done , and you will get a dummy page like this :

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     now the time comes to deploy your diagram , before that u have to provide java class for service task and , user name , form field,assignee for user task .... etc .

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     now when u deploy , it will deploy into your current running application .

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     once you deployed , you can see the xml into your project:

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     once this done go to your page , create user i.e manager and hr , than start the process .

   • once you start the process you can see the logs in your eclipse .

     

     

     And If You notice in cockpit , now its pointing to Manager approval , when manager approve it goes to HR and so on..🤩🤩