SMQP

Synchronous message queueing package. Used as an alternative, and frontend ready, event handler when you expect events to be handled in sequence.

Basically a synchronous amqp broker.

Documentation

• API

Usage

import { Broker } from 'smqp';

const owner = { name: 'me' };
const broker = Broker(owner);

broker.subscribe('events', '#', 'event-queue', onMessage);

broker.publish('events', 'start', { arg: 1 });

function onMessage(routingKey, message, brokerOwner) {
  console.log('received:', routingKey);
  console.log('with message:', message);
  console.log('owned by:', brokerOwner.name);
  message.ack();
}

Changelog

Unreleased

[9.0.6] - 2025-02-04

• some ticks saved by letting the queue queue a published message rather than handing it over to internal exchange._publishToQueue to queue the published message
• es5 trailing commas touched all files

[9.0.5] - 2025-01-02

• get returns false if there is no consumable message on queue, as stated in doc
• make sure api is exposed as expected

[9.0.4] - 2024-12-17

• export MessageMessage and ShovelOptions from fussy type declarations

[9.0.3] - 2024-11-08

• attempt to fix whiny type declarations

[9.0.2] - 2024-06-14

• no need to sort single binding or consumer by priority or if priority is not supplied

[9.0.1] - 2024-06-10

• stop emitting queue message event when message is queued, no listeners AFAIK

[9.0.0] - 2024-06-08

Breaking

• exchange-, shovel-, and queue name are read-only
• stop emitting exchange bind and unbind events, no listeners AFAIK
• broker.getConsumer(consumerTag) requires consumer tag to be a string

Fixes

• replace entities arrays with new Map() to gain some performance
• fix API.md getRoutingKeyPattern example, destructing a method from an prototyped instance doesn't work
• run through markdown examples with texample

[8.2.4] - 2024-04-19

• using prettier for formatting rules was mistakenly considered a production dependency. Now it is back where it belong.

[8.2.3] - 2024-04-08

• major update of eslint
• use prettier for formatting rules, touched basically ALL files

[8.2.2] - 2024-02-03

• broker.getConsumers() now also returns if the consumer is ready or not. Cannot remember why, but the info is there

[8.2.1] - 2023-10-21

• export Message, Queue, Consumer, and Exchange
• allow queue event options queue.on(event, handler[, options])
• cancelling a consumer returns true if consumer was found and false if not
• broker.get(queueName, { noAck: true }) not only dequeues message it also marks the actual message as consumed on the, until now, undocumented message.pending flag
• fix other inconsistent message pending stuff

[8.2.0] - 2023-09-03

• introduce SmqpError(message, code) inherited from Error, it is thrown when package specific errors occur. It is also exported so that instance can be checked
• no more general errors, either it is a TypeError or SmqpError
• fix inconsistent cancel consumer implementations in queue, add requeue argument when applicable

[8.1.0] - 2023-08-26

• noAck consumer continues consuming if error is thrown in message callback, the error is, hopefully, caught somewhere else
• ack consumer continues consuming if error is thrown in message callback after message was acked
• add some Broker, Queue, Exchange, Shovel, and Consumer argument constraints
• fix exchange to exchange binding type

[8.0.0] - 2023-06-22

• shovel ignores shoveling if destination exchange lacks bindings, could be breaking if cloneMessage function option was used to make things happen
• abide to new lint rules
• bump all dev dependencies

[7.1.4] - 2023-04-05

• type declare broker state from getState()

7.1.3

• no need to type declare that a function can return undefined, prevents assigning a typed variable
• return undefined instead of false if deleting non-existing queue
• return undefined instead of false if no message on queue.get

7.1.2

• Fix queue recover not returning instance of Queue when recovering without state
• and some typing blunders

7.1.1

• Fix type declaration forbidden override and boolean typo. Introduce circular type import in Shovel, which apparently is ok!?

7.1.0

• Add type declarations

7.0.0

• Turn into module with exports for node
• Rename symbol declarations for no reason at all

6.1.0

• Minor performance tweek by prototyping routing key patterns
• Stop building node 12
• Lint some

6.0.0

Breaking

• Message functions ack, nack, and reject, if deconstructed, must be called with call or apply since they are no longer bound to instance. Sacrificed in the name of performance, sorry about that
• Internal Message function consume is renamed to _consume
• Internal and/or undocumented functions are renamed and decorated with underscore, some where even - highly unnecessary - Symbols
• exchange.bind renamed to exchange.bindQueue to mitigate JavaScript confusion
• consequentely the exchange.unbind function is renamed to exchange.unbindQueue
• broker.cancel(consumerTag) signature changed to broker.cancel(consumerTag[, requeue = true]). This breaks current behaviour for ack consumers, i.e. messages waiting for ack will be requeued by default if the consumer is cancelled. For some reason they were requeued in the previous version, even though nackAll was called? For no-ack consumers this won't have an affect at all

Additions

• *.get() returns false if no message was retrieved

Fixes

• Fix inconsistent cancel consumer behaviour between broker, queue, and consumer

5.1.3

• minor, probably futile, tweaks

5.1.2

• give a hint of which Queue throws circular JSON when getting state

5.1.1

• no side effects

5.1.0

Slimmer state

• Add argument to getState that tells the broker to only return stuff that actually has content, i.e. messages and undelivered exchange messages

5.0.0

Attempt to tweak performance by removing stuff. Consequently some things broke.

Breaking

• Remove support for node 10 (mochas fault)
• Message property consumerTag is removed, can be found by message.fields.consumerTag
• Message property messageId is removed, can be found by message.properties.messageId
• Remove onMessageQueued argument from queue.queueMessage function
• Remove queue.dequeueMessage(message) function
• Change routing key pattern hash (#) handling to /.*?/ from /.+?/

Fixes

• Fix pattern matching bug if more than one wildcard

4.0.0

For performance reasons the Broker has been prototyped. Thank you @roberto-naharro and co for discovering and resolving this (#5). This means that functions cannot be deconstructed and called without binding or using call/apply.

3.2.0

Slimmer and swifter state.

• getState: Only use JSON-fns when really necessary (= messages)
• Stop dead lettering messages when queue is deleted. Did some deep forrest coverage hunting and found no scenario when this has ever worked, maybe since it isn't part of RabbitMQ behaviour

3.1.0

Coverage hunting.

• Stop consumers when queue is stopped
• Remove setter for message consumerTag

3.0.1

• Sometimes you need the name of the event, especially if you listen with wildcards. The name is an exact match of the emitted message routing key.

3.0.0

Confirm messages and node 10 and above.

Breaking changes

• Drop nodejs 8 support, or at least for tests due to mocha

Additions

• New message confirm option, will emit message.nack, message.ack, or message.undelivered on broker
• Support offing broker events by consumerTag
• Support offing exchange events by consumerTag

2.2.0

• Add broker function getConsumers() to get the list of consumer properties

2.1.1

• Ignore published message if no one is listening, unless it is mandatory

2.1.0

• Support changing destination exchange key in shovel
• Support overwriting shoveled message properties

2.0.1

• Support passing source binding priority to shovel or bound exchange

2.0.0

Breaking changes

• createShovel has changed signature: last argument cloneMessage is converted to an args object, and cloneMessage moved to a property of args

Additions

• Introduce e2e by bindExchange and consequentaly unbindExchange, shoveling messages between exchanges

1.11.1

• Fix consumer eventlistener not working at all due to messed up binary code
• Close shovel if source consumer is closed

1.11.0

Additions

• Introduce shovel, shoveling messages between brokers

1.10.0

Additions

• Support message expiration and queue messageTtl

Fixes

• Acked messages were sent to dead letter exchange, they shouldn't, and are not anymore

1.9.0

• Add ability to reset everything, i.e. queues, exchanges, consumers you name it

1.8.0

• Support turning off queue event listener - queue.off(eventName, handler)

1.7.0

• subscribeOnce also takes priority option, as it should've from the beginning

1.6.0

• Support turning off event listener with off(eventName, handler)

1.5.0

• Non-persistent message, message option persistent = false, will not be recovered when recovering from state

1.4.1

• A recovered queue with messages always considers messages redelivered, regardless if queue was stopped or not

1.4.0

• Export getRoutingKeyPattern

1.3.0

• Expose broker owner

1.0.0

Breaking changes

• sendToQueue has changed signature: argument routingKey is omitted, since it had nothing to do there anyhow
• Message in message callback has changed:
  • introduced new property named fields
  • .routingKey is moved to fields.routingKey along with new and fresh exchange and consumerTag properties
  • .options is renamed to .properties