API reference / @node-ts/bus-core / Handler

Interface: Handler<TMessage, TMessageAttributes>

Defined in: packages/bus-core/src/handler/handler.ts:20

Implemented by a class to indicate it acts as a handler for a given message

Type Parameters

Type Parameter	Default type
TMessage extends MessageBase	MessageBase
TMessageAttributes extends MessageAttributes	MessageAttributes

Properties

Property	Type	Description	Defined in
messageType	MessageDeclaration<TMessage & Message>	The type of message the class handles: a message class, or a definition from defineCommand or defineEvent. Define it as a getter (get messageType() { return MyEvent }) so that withHandler() can read it without constructing the handler. A class field is only readable from an instance, so the handler is constructed without its dependencies when it's registered.	packages/bus-core/src/handler/handler.ts:30

Methods

handle()

handle(
   message, 
   attributes, 
   context
): unknown;

Defined in: packages/bus-core/src/handler/handler.ts:39

A function that is called each time a message of messageType is received

Parameters

Parameter	Type	Description
message	TMessage	The message read from the bus
attributes	TMessageAttributes	Attributes of the message read from the bus
context	HandlerContext	Sends, publishes, fails or returns messages through the bus that received the message

Returns

unknown

Anything. A returned promise is awaited, and the value it resolves to is ignored