Glossary¶

Aggregate¶

A cluster of domain objects treated as a single unit for data changes. An aggregate has a root entity that controls all access to objects inside the boundary. External references are only allowed to the root.

Bounded Context¶

A boundary within which a particular domain model applies. Different bounded contexts may have different models for the same real-world concept.

Consumer Group¶

A set of consumers that share the processing load for a stream of messages. Each message is delivered to exactly one consumer within the group.

Distributor¶

In the faker module, a strategy that controls how test data is selected from a pool or when new data must be created. Examples: sequence (round-robin), weighted (probability-based), random.

Domain Event¶

A record of something that happened in the domain. Domain events are used to communicate between aggregates and bounded contexts.

Entity¶

A domain object defined by its identity rather than its attributes. Two entities with the same identity are considered the same object regardless of their current attribute values.

Inbox¶

A pattern for idempotent message processing. Each incoming message ID is recorded; duplicate messages are detected and skipped.

Outbox¶

A pattern where domain events are written to a database table (the outbox) within the same transaction as the business operation. A separate process reads the outbox and publishes events to the message broker.

Provider¶

In the faker module, a component responsible for generating or selecting a specific piece of test data. Providers form a directed acyclic graph where reference providers link aggregates.

Repository¶

A collection-like interface for accessing aggregates. Repositories abstract the persistence mechanism, allowing domain logic to remain independent of storage details.

Saga¶

A sequence of local transactions coordinated to implement a distributed business process. Each step has a compensating action that undoes its effect if a later step fails.

Session¶

An implementation of the Unit of Work pattern. A session tracks changes to aggregates and commits them atomically to the database.

Specification¶

An object that encapsulates a boolean predicate over domain objects. Used to express query criteria, validation rules, or selection logic in a composable and reusable way.

Unit of Work¶

A pattern that maintains a list of objects affected by a business transaction and coordinates the writing of changes and resolution of concurrency problems.

Value Object¶

A domain object defined entirely by its attributes, with no conceptual identity. Value objects are immutable and compared by value equality.