Events

WeOS uses event sourcing. All state changes are captured as immutable domain events. This page catalogs every event type, its payload, and when it fires.

ResourceType Events

Pattern: ResourceType.%

ResourceType.Created

Fired when a new resource type is registered (via preset install, CLI, or API).

Field	Type	Description
Name	string	Display name
Slug	string	URL-safe identifier
Description	string	Type description
Context	json.RawMessage	JSON-LD context
Schema	json.RawMessage	JSON Schema
Timestamp	time.Time	When the event occurred

ResourceType.Updated

Fired when a resource type’s definition is modified.

Field	Type	Description
Name	string	Updated name
Slug	string	Updated slug
Description	string	Updated description
Context	json.RawMessage	Updated JSON-LD context
Schema	json.RawMessage	Updated JSON Schema
Status	string	Updated status
Timestamp	time.Time	When the event occurred

ResourceType.Deleted

Fired when a resource type is archived.

Field	Type	Description
Timestamp	time.Time	When the event occurred

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Resource Events

Pattern: Resource.%

Resource.Created

Fired when a new resource is created.

Field	Type	Description
TypeSlug	string	Resource type slug
Data	json.RawMessage	Full JSON-LD data
CreatedBy	string	Creator’s agent ID
AccountID	string	Owning account ID
Timestamp	time.Time	When the event occurred

Resource.Updated

Fired when a resource’s data is modified.

Field	Type	Description
Data	json.RawMessage	Updated JSON-LD data
Timestamp	time.Time	When the event occurred

Resource.Deleted

Fired when a resource is archived (soft-deleted).

Field	Type	Description
Timestamp	time.Time	When the event occurred

Resource.Published

A signal event fired after all creation events for a resource have been committed. This tells event handlers that the resource’s data and relationships are fully available.

Field	Type	Description
TypeSlug	string	Resource type slug
Timestamp	time.Time	When the event occurred

This event is the primary trigger for projection writes. See ADR: Event Handler Data Availability.

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Triple Events

Pattern: Triple.%

Triple events are recorded on the resource entity (same event stream). They model RDF relationships between resources.

Triple.Created

Fired when a relationship between two resources is established.

Field	Type	Description
Subject	string	Source resource URN
Predicate	string	Relationship IRI (e.g., https://schema.org/isPartOf)
Object	string	Target resource URN
Timestamp	time.Time	When the event occurred

Triple.Deleted

Fired when a relationship between two resources is removed.

Field	Type	Description
Subject	string	Source resource URN
Predicate	string	Relationship IRI
Object	string	Target resource URN
Timestamp	time.Time	When the event occurred

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Event Lifecycle

A typical resource creation produces this event sequence:

1. Resource.Created    — entity data stored
2. Triple.Created      — relationship(s) recorded (if any x-resource-type properties)
3. Resource.Published  — signal that all events are committed

Event handlers should:

• Subscribe to Resource.Published for projection writes (not Resource.Created)
• Be idempotent — the same event may be delivered more than once
• Never modify events after they’re stored

Subscribing to Events

Event handlers subscribe via pattern matching in application/module.go:

domain.Subscribe[any](dispatcher, "Resource.%", myHandler)    // all resource events
domain.Subscribe[any](dispatcher, "ResourceType.%", myHandler) // all type events

The % wildcard matches any suffix.