WorkflowEngine

WorkflowEngine is a software component that manages the execution of defined workflows, coordinating a series of tasks or services to achieve a business objective. It interprets a workflow definition, starts activities, passes data between steps, and tracks progress and outcomes. The engine typically provides persistence for workflow state, a lifecycle for each instance, and an API for external systems to interact with running workflows.

A workflow is described using a definition language or DSL that encodes the sequence, conditions, parallelism, and data flow. Tasks in a workflow can be automated services, data transformations, or human-in-the-loop activities. The engine stores the current state of each active workflow instance and may support versioned definitions, data schemas, and audit trails. Execution supports branching, parallel execution, event-based triggers, and conditional logic; error handling includes retries, backoff, and compensating actions to maintain consistency.

In operation, a WorkflowEngine may start a workflow instance with input data, invoke activities, wait for results or external signals, and eventually produce an output. It handles failures by retrying steps or invoking alternative paths, and it may offer auditing, monitoring, and alerts. Security, access control, and multi-tenant separation are common concerns, as is the ability to pause, resume, or terminate workflows.

WorkflowEngines appear in embedded form within applications or as standalone services. They often provide integration points such as REST or gRPC APIs, message bus hooks, and connectors to databases or service endpoints. Some engines implement standards like BPMN or offer proprietary DSLs to model processes.