fastify-queue

An async queue for Fastify.

Usage

``sh
npm i @autotelic/fastify-queue
`
#### Example

`js
const fastifyQueue = require('@autotelic/fastify-queue')

function myRoute (fastify, opts) {
fastify.register(fastifyQueue)

fastify.post('/example', async (request, reply) => {
reply.queue.add('async-action-one', reply.asyncAction())
reply.queue.add('async-action-two', reply.asyncActionTwo())
reply.queue.add('async-action-three', reply.asyncActionThree())
// Manual resolution optional - queue will otherwise resolve in onResponse hook.
const results = await reply.queue.resolve()
reply.status(200)
})
}
`

API

$3

fastify-queue accepts the following optional configuration:

- #### initializer: (key: string, value: any, reply: FastifyReply) => any | Promise
- Called each time an item is added to the queue. The value returned will be the value added to the queue.

- #### resolver: (key: string, value: any, reply: FastifyReply) => any
- Called each time an item in the queue is resolved. value is the resolved value of an item in the queue.

- #### onError: (error: Error, reply: FastifyReply) => any
- Called if an error occurs while resolving the queue. Defaults to fastify.log.error(error).

- #### onResolved: (result: any, reply: FastifyReply) => void
- Called after the queue has successfully resolved. result is the resolved queue.

- #### queueName: string
- Determines the name of the reply decorator added by the plugin. Defaults to 'queue'.

- #### concurrency: number
- Max number of concurrently pending promises. Defaults to Infinity.
- This value is passed directly to p-props options param.

- #### stopOnError: boolean
- When set to false, errors thrown while resolving items in the queue will be accumulated. Once all items in the queue have settled, a single aggregated error will be thrown.
- This value is passed directly to p-props options param.




$3

fastify-queue adds a queue (or the value of opts.queueName) reply decorator containing the following properties:

- #### add: (key: string, value: any) => void
- Used to add items to the queue.

- #### resolve: (cb?: (result: any, reply: FastifyReply) => void) => void
- Used to manually resolve the queue. cb defaults to opts.onResolved.
- fastify-queue will automatically resolve the queue in an onResponse hook, if this has not already been called.

- #### contents: Map
- The queue Map` instance.