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

Class: InMemoryQueue

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:40

An in-memory message queue. This isn't intended for production use as all messages are kept in memory and hence will be wiped when the application or host restarts.

There are however legitimate uses for in-memory queues such as decoupling of non-mission critical code inside of larger applications; so use at your own discretion.

Implements

• Transport<InMemoryMessage>

Constructors

Constructor

new InMemoryQueue(memoryQueueConfiguration?): InMemoryQueue;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:53

Parameters

Parameter	Type
memoryQueueConfiguration	InMemoryQueueConfiguration

Returns

InMemoryQueue

Accessors

deadLetterQueue

Get Signature

get deadLetterQueue(): TransportMessage<InMemoryMessage>[];

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:212

Returns all messages sitting in the dead letter queue. This is a copy of the queue so mutative actions on this array will have no consequence.

Returns

TransportMessage<InMemoryMessage>[]

---

deadLetterQueueDepth

Get Signature

get deadLetterQueueDepth(): number;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:204

Returns

number

---

depth

Get Signature

get depth(): number;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:200

Gets the queue depth, which is the number of messages both queued and in flight

Returns

number

---

numberMessagesVisible

Get Signature

get numberMessagesVisible(): number;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:219

Gets the number of messages in the queue, excluding those in flight

Returns

number

Methods

deleteMessage()

deleteMessage(message): Promise<void>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:154

Removes a message from the underlying transport. This will be called once a message has been successfully handled by any of the message handling functions.

Parameters

Parameter	Type	Description
message	TransportMessage<InMemoryMessage>	The message to be removed from the transport

Returns

Promise<void>

Implementation of

Transport.deleteMessage

---

dispose()

dispose(): Promise<void>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:77

Cancels pending retries and reads so that the queue doesn't keep the process alive

Returns

Promise<void>

Implementation of

Transport.dispose

---

fail()

fail(transportMessage): Promise<void>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:104

Forwards

Parameters

Parameter	Type	Description
transportMessage	TransportMessage<InMemoryMessage>	to the dead letter queue. The message must have been read in from the queue and have a receipt handle.

Returns

Promise<void>

Implementation of

Transport.fail

---

initialize()

initialize(options?): Promise<void>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:68

Records which messages have local handlers. Messages without one are discarded when sent.

Parameters

Parameter	Type	Description
options?	TransportInitializationOptions	the handler registry of the bus

Returns

Promise<void>

Implementation of

Transport.initialize

---

prepare()

prepare(coreDependencies): void;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:57

An optional function that is called before startup that will provide core dependencies to the transport. This can be used to fetch loggers, registries etc that are used in initialization steps

Parameters

Parameter	Type
coreDependencies	CoreDependencies

Returns

void

Implementation of

Transport.prepare

---

publish()

publish<TEvent>(event, messageOptions?): Promise<void>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:90

Publishes an event to the underlying transport. This is generally done to a topic or some other mechanism that consumers can subscribe themselves to

Type Parameters

Type Parameter
TEvent extends Event

Parameters

Parameter	Type	Description
event	TEvent	A domain event to be published
messageOptions?	MessageAttributes<MessageAttributeMap, MessageAttributeMap>	Options that control the behaviour around how the message is sent and additional information that travels with it.

Returns

Promise<void>

Implementation of

Transport.publish

---

readNextMessage()

readNextMessage(): Promise<
  | TransportMessage<InMemoryMessage>
| undefined>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:114

Returns the next visible message. If none are visible, waits until one becomes visible or receiveTimeoutMs elapses, in which case undefined is returned.

Returns

Promise< | TransportMessage<InMemoryMessage> | undefined>

Implementation of

Transport.readNextMessage

---

returnMessage()

returnMessage(message): Promise<void>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:171

Returns a message to the queue for retry. This will be called if an error was thrown when trying to process a message.

Parameters

Parameter	Type	Description
message	TransportMessage<InMemoryMessage>	The message to be returned to the queue for reprocessing

Returns

Promise<void>

Implementation of

Transport.returnMessage

---

send()

send<TCommand>(command, messageOptions?): Promise<void>;

Defined in: packages/bus-core/src/transport/in-memory-queue.ts:97

Sends a command to the underlying transport. This is generally done to a topic or some other mechanism that consumers can subscribe themselves to

Type Parameters

Type Parameter
TCommand extends Command

Parameters

Parameter	Type	Description
command	TCommand	A domain command to be sent
messageOptions?	MessageAttributes<MessageAttributeMap, MessageAttributeMap>	Options that control the behaviour around how the message is sent and additional information that travels with it.

Returns

Promise<void>

Implementation of

Transport.send