RegistryDefinition Design Overview
The RegistryDefinition aggregate defines the high-level structure and lifecycle for managing registry definitions. It follows the CQRS (Command Query Responsibility Segregation) pattern, separating state-changing operations ( commands) from state queries (events and read models).
Purpose
The system manages definitions that describe business entities and rules using a JSON schema. These definitions govern how data is structured and controlled, including aspects like:
Relationships
Credentials
Roles
Access to private fields
Key Concepts
Versioning
Each definition has a version to track changes over time. Versions are always positive and increment with each update.
Definition Identifier
Each definition is uniquely identified using a UUID-based ID.
Definition Status
A definition moves through various lifecycle stages:
None– Initial stateDraft– Work-in-progressValid– Successfully validatedActive– In useDeactivated– Not in useInvalid– Validation failedMarkedForDeletion– Scheduled for removalModified– Changed but not yet revalidated
Events
All changes are recorded as domain events, such as:
Definition created
Definition updated
Validation passed or failed
Definition activated or deactivated
Definition deleted or loaded from storage
Events include metadata like timestamps and user details.
Errors
Errors can occur due to:
Invalid schema data
Invalid state transitions
Metadata mismatches (e.g., title)
State Management
The RegistryDefinition aggregate maintains:
A unique identifier
Current status
Version number
Title
The JSON schema string that defines business rules and structure
State Transitions
State transitions are managed via a state machine that enforces:
Valid paths between statuses
Business rules for moving between states
Operations
The system supports the following operations:
Create a new definition
Update an existing definition
Validate a definition's schema
Activate or deactivate a definition
Delete a definition
Load a definition from storage
Each operation triggers corresponding domain events and follows strict rules.