# Pynenc Workflow Development Plan

Building on our task-centric approach to workflows, this development plan outlines the implementation steps from simple to complex features, using test-driven development with both unit and integration tests.

## Implementation Roadmap

### Phase 1: Core Workflow Identity and Propagation

1. **Basic Workflow Identity Propagation**

   - Complete unit tests for `WorkflowIdentity` creation and propagation
   - Ensure child tasks inherit parent workflow context properly
   - Test workflow boundaries with `force_new_workflow` flag

2. **Workflow Creation Rules**
   - Test automatic workflow creation for standalone tasks
   - Test workflow inheritance for tasks executed within workflows
   - Verify workflow hierarchy in subworkflow scenarios

### Phase 2: Workflow State Management

3. **Deterministic Operations**

   - Test deterministic random number generation
   - Test deterministic time functions
   - Test deterministic UUID generation
   - Ensure values persist across workflow restarts

4. **Workflow State Persistence**
   - Implement custom state storage and retrieval
   - Test state persistence across task failures
   - Test state isolation between different workflow instances

### Phase 3: Workflow Control Flow

5. **Workflow Pausing and Resuming**

   - Implement and test workflow pause mechanism
   - Test resuming workflows from paused state
   - Verify correct state restoration on resume

6. **Workflow Event Handling**
   - Test external signal handling
   - Test event-based workflow continuation
   - Test timeout and timer functionality

### Phase 4: Workflow Execution Features

7. **Error Handling and Recovery**

   - Test retry behavior for workflow tasks
   - Test compensation/cleanup logic for failures
   - Test partial workflow recovery scenarios

8. **Advanced Workflow Patterns**
   - Test parallel task execution within workflows
   - Test conditional branch execution
   - Test dynamic task generation based on workflow state

### Phase 5: Observability and Tooling

9. **Workflow Monitoring and Visualization**

   - Implement workflow status page in monitoring UI
   - Add workflow graph visualization
   - Add workflow execution history view

10. **Workflow Debugging Tools**
    - Implement workflow replay capability
    - Add detailed logging for workflow state transitions
    - Create workflow inspection tools for the CLI

## Testing Strategy

Our testing approach combines unit tests for individual components and integration tests for workflow scenarios:

### Unit Tests

| Test Category   | Purpose                                            | Files                                    |
| --------------- | -------------------------------------------------- | ---------------------------------------- |
| Identity Tests  | Verify workflow identity creation and propagation  | `tests/unit/workflow/test_identity.py`   |
| State Tests     | Test state persistence and retrieval               | `tests/unit/workflow/test_state.py`      |
| Context Tests   | Test deterministic operations and workflow context | `tests/unit/workflow/test_context.py`    |
| Exception Tests | Verify handling of workflow exceptions             | `tests/unit/workflow/test_exceptions.py` |

### Integration Tests

| Test Category     | Purpose                                      | Files                                                  |
| ----------------- | -------------------------------------------- | ------------------------------------------------------ |
| Basic Workflow    | Test simple linear workflow execution        | `tests/integration/workflow/test_basic_workflow.py`    |
| Nested Workflow   | Test parent-child workflow relationships     | `tests/integration/workflow/test_nested_workflow.py`   |
| Error Recovery    | Test workflow recovery from failures         | `tests/integration/workflow/test_error_recovery.py`    |
| State Persistence | Test long-running workflows with persistence | `tests/integration/workflow/test_state_persistence.py` |
| Control Flow      | Test branching and conditional workflows     | `tests/integration/workflow/test_control_flow.py`      |

### Monitoring Views

The monitoring system will be enhanced with the following workflow-specific views:

1. **Workflow Overview**: List of all workflows with status, duration, and task count
2. **Workflow Detail**: Detailed view of a single workflow with task hierarchy
3. **Workflow Graph**: Visual representation of workflow task dependencies
4. **Execution History**: Timeline of workflow events and state changes
5. **Workflow Inspector**: Tool to examine and modify workflow state

## Implementation Strategy

For each feature:

1. Write failing tests defining the expected behavior
2. Implement the minimum code to pass the tests
3. Refactor for clarity and performance
4. Add monitoring capabilities for the feature
5. Document usage patterns and best practices

This incremental approach ensures each component is fully functional before moving to more complex features, while maintaining backward compatibility with the existing task system.
