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This article mainly introduces the example analysis of workflow architecture and implementation in the Internet, which is very detailed and has a certain reference value. Interested friends must read it!

Workflow systems and some representative patterns of human-business process interaction are divided into two main components. The * components are workflow systems and the interaction between them when they are implemented on an integrated platform. The second component is workflow interaction design patterns and how these patterns are implemented using interactions between workflow systems. This discussion describes these processes in detail.

Full automation of business processes is virtually impossible without taking into account human interaction, which is semantically related to many aspects of process automation and integration. Human interaction exists in some of the most common business processes, such as order approval and human resource management. These human interactions range from simple task allocation processes to very complex business process notifications and task reassignment.

Workflow frameworks are available in a variety of popular integration servers from different vendors. We will conceptually explore some of the major components that exist in workflow platforms and their interactions. We will also introduce some of the most common workflow design patterns and how to implement them using the above components.

The workflow system must support the communication between people and systems. To achieve this support, each workflow system must provide basic functions such as task assignment, identity management, notification, tracking, and interoperability with business process management (BPM) systems (see figure 1).

Figure 1

The four main components of workflow architecture are task management service, tracking service, notification service and identification service. Before delving into these services, you need to understand the role of tasks in workflow systems.

Tasks are the main communication units between business processes and people. Typically, tasks are assigned to users who need to perform a related action. For example, a supervisor may need to approve a request for the purchase of certain goods. Typically, the user must perform a series of tasks that are combined according to semantics. In other words, the supervisor may combine all the goods that need to be purchased every day into a group called "Today's approvals". These groups are called task lists.

Task status

During the lifetime of the workflow system, the tasks in the task list continue to switch from one state to another. For example, the supervisor's task first enters the "pending" state; after the supervisor accepts the task, the status changes to "claim". * when the supervisor approves the request, the task enters the final state of "complete". State is used to conceptually describe task lifetime. Some of the most common states are pending, claimed, completed, and failed. In the "pending" state, the task has been created; in the "claimed" state, the user claims the task and receives the task input data; in the "complete" state, the user has completed the task and provided the output data of the task; in the "failed" state, the user has completed the task and provided an error message.

Tasks are usually associated with a time frame: expiration, upgrade, delegation, and renewal. In our example, if the supervisor does not process the approval task within the specified period of time, the task may expire. This expired task can then be upgraded to another operation or assignment process. The supervisor may also decide to delegate the task to another person (for example, the manager) to perform the task in his or her place. The manager can also decide whether to involve another manager in order to collect other opinions. If the second manager does not work on this task within the given time frame, the task will be renewed to be executed within another time period.

In other scenarios, tasks are semantically related to each other. To the question, "what's the next task?" The answer is not always insignificant. In some cases, the answer must be determined at run time. Tasks can be grouped sequentially into a business process instance so that users know the next task to perform after completing the current task.

In our example, the supervisor needs to approve 20 requests in turn to complete the business process. Each time the supervisor completes an approval, the engine should be able to identify the next task. "Task chain" represents a metadata-driven approach that describes the relationship between a set of tasks within the scope of a business process. Task chains can combine tasks semantically to help users achieve certain functions, such as sequential execution and failure management.

Tasks that depend on specific business processes are called inline tasks. Tasks that are completely independent of a particular business process are independent tasks. Inline tasks can usually access data related to a business process and store it in local, business process elements such as variables or messages. In contrast, independent tasks interact with the business process through a well-defined interface and are completely independent of the process data itself.

Workflow service

The architectural component that handles local tasks is the task management service. In a typical scenario, the task management service receives a task creation request, interacts with the identification service to select all the people who are qualified to perform the task, and adds the task to the worklist (work to be completed) associated with the selected user. And assign specific timelines and policies. In the end, a user decides to process the task by claiming it. The user can then process the task or request more data.

A key aspect of a workflow system is the ability to parse the set of users that are allowed to perform tasks. This user resolution process can be based on interaction with the identity management platform. In our example, the workflow service needs to identify which users can approve the request, in this case the supervisor. To accomplish this identification, the workflow platform must resolve the concept of "supervisor" against a set of users and roles traditionally stored in the user directory.

Many types of relationships can be established between people and processes. One of the most common relationships is the way people interact with processes (human roles). You can combine people in your organization into roles that are semantically related to a business activity, such as a process administrator or task owner. Another common relationship is how the process identifies who to interact with (people links and queries). In business processes, some user groups are relevant from a business point of view. Person links are used to represent different groups of people who are involved in the execution of the process. Queries against the organizational directory are used to determine the individual associated with the person link and are bound to the person link. In our example, the ordinary human role-the financial manager can be defined by the personnel link supervisor, who is bound to the following query: "Select the department leader, where the department name is Finance."

Identity services are responsible for user-related functions, such as authentication, authorization, or personnel resolution. User information is typically stored in organizational directories (for example, Active Directory directory services, LDAP directories, or relational databases). Identity services can work independently of the organizational directory. Depending on the adapter pattern, directory access can be extracted through a provider, which can execute queries to get the information in the directory. This method can extract workflow functionality from the user's store.

In our example, suppose the manager wants to rebuild the execution of the request-approval workflow to check for shortages. The tracking service can track state changes related to tasks and task chains. This service should provide the basis for the required functionality to rebuild task history changes and perform task analysis.

When creating a request-approval task, we also need a service that can notify the supervisor via email. The notification service handles the mechanism for sending notifications to users associated with changes in the status of a task.

The four runtime services discussed here provide a good overview of some of the most common features required by workflow systems. By combining these services, you can handle some of the most common workflow scenarios. Now, let's explore some common workflow patterns.

Task assignment mode

Workflow-oriented processes have existed in the industry for several years. The knowledge gained can be used as the basis for improvement to build a workflow system. Patterns abstract workflow systems at different levels, such as task approval, task creation, and task state management. Here, we do not intend to define the classification of workflow patterns. Instead, we will introduce some common patterns in workflow systems from the perspective of previously defined architectures.

We will start by looking at the single-user Workflow example. You can assign a task to one user, and only one user can handle the task. For example, an employee submits a leave request through the employee portal. The portal initiates a business process that includes a user task modeled using a simple workflow. The task is assigned to the manager of this employee. When the manager approves or rejects the leave request, inform the employee of the manager's decision by email.

For this solution, the workflow components are combined through four interactions. The task is configured using a client application that interacts with the task management service; the lifetime or status of the task is configured. As part of the business process, use the task management service to assign tasks to user groups. One of the users claims the task, and the task management service applies the correct policy to prevent other users from working on the same task. The business process uses the task management service to obtain status updates for the task.

Now, let's consider an example of a sequential workflow. A sequential workflow represents a scenario in which tasks must be approved sequentially by a group of users. For example, when the purchase order approval system uses a business process to process a purchase order, an employee who belongs to the Supervisor group makes a preliminary evaluation of the purchase order. After the initial user approves the purchase order, it is approved by the user's manager. After the manager's approval, the purchase order is forwarded to the billing and transportation department. The solution consists of four interactions. Interact with the task management service to configure tasks and set appropriate policies. Define the order of users who should process tasks. Start a task that interacts with the task management service. * users will claim the task to start processing it, and when the process is complete, the task management service will transfer the task to the next user in the group.

The parallel workflow pattern represents the following scenario: a task must be approved by different users at the same time. Each approver can add comments and attachments independently of others. For example, the recruitment process is used to recruit new employees. Every interviewer needs to vote for or against the candidate. If 75% of the votes are in favor, the candidate will be hired; otherwise, the candidate will be defeated. This process is modeled using parallel workflows, where each interviewer can vote independently of other interviewers. Five interactions are required to implement the solution. Interact with the task management service to configure tasks and set appropriate policies. Define the order of users who should process tasks. Start a task that interacts with the task management service. The task management service delivers the task to all users. The task management service can complete the task only if all users have completed the task.

Use policies for task assignment

Now, let's discuss how to use the strategy of task assignment, according to which you need to follow specific rules to assign tasks to users. For example, the procedure of cardiac bypass surgery is assigned to the surgeon who has the least number of operations. The implementation of this solution combines workflow components through five interactions. Interact with the task management service to configure tasks and set appropriate policies. Configure the allocation policy as part of the task definition-for example, select the one with the least number of tasks assigned from the available users. As part of the business process, use the task management service to assign tasks to user groups. Start a task that interacts with the task management service. The task management service executes the task policy for potential users who can handle the task, and then does the following in turn: select the user who meets the policy criteria, and assign the task to that user.

In the single user Workflow with upgrade example, you can assign a task to multiple users, but only one user can handle the task. If the task expires, the user's manager must handle the task. For example, the technical support service request process enables the user to submit a technical support service request ticket. If the person who received the ticket did not process the ticket within the specified period of time, the ticket is automatically upgraded to that person's manager. If no one processes the ticket within a predefined period of time, the ticket is automatically upgraded three times until it reaches the company's CEO. If the CEO does not process it, the ticket expires.

For the implementation of this solution, the workflow components are combined through five interactions. Tasks are configured using client applications that interact with task management services; properties such as task lifetime, upgrade policy, or task status are configured in this step. As part of the business process, use the task management service to assign tasks to user groups. A user claims the task, and the task management service applies the correct policy to prevent other users from performing the same task. If the task expires, the task management service applies the upgrade policy to upgrade the task to the correct user. If the task expires again, the Task Management Service cancels it.

In the single user Workflow using delegation example, a user who claims to process a task can reassign the task to another user. For example, before leaving, the accounting director gives all his or her unfinished tasks to the assistant accountant. For the implementation of this solution, the workflow components are combined through four interactions. Tasks are configured using client applications that interact with task management services; properties such as task lifetime, upgrade policy, or task status are configured. As part of the business process, use the task management service to assign tasks to user groups. A user claims the task, and the task management service applies the correct policy to prevent other users from performing the same task. Using the appropriate client application, the user can check the list of possible people who can handle the task. The user reassigns the task to one of the above people and adjusts the properties of the task.

For the Task chain Mode example, one task needs to be started based on the completion status of another task. For example, in the first aid coordination process, when the previous work item is completed, start the next work item immediately. To implement this solution, you can combine workflow components through four interactions. Tasks are configured using client applications that interact with task management services; properties, such as the lifetime or status of the task, are configured. Task chain metadata is configured to indicate that the second task will be triggered by the completion of * tasks. Start the task chain through the task management service, so that * tasks can be started. When * tasks are completed, the task management service uses the metadata in the task chain to start the second task.

Business process integration

You can combine services such as task management, identity management, tracking, notification, and client applications to design workflow solutions. We have explored some of the most common components that exist in the workflow architecture and their implementation in a series of interactions. You can use a set of human interaction patterns to model some of the most complex human-system interactions, which are implemented using workflow components. These basic components and patterns of workflow architecture represent key aspects in the field of business process integration, and they can be implemented to create powerful workflow solutions.

The above is all the contents of the article "example Analysis of Workflow Architecture and implementation in the Internet". Thank you for reading! Hope to share the content to help you, more related knowledge, welcome to follow the industry information channel!

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