a leveldb backed Queue
- durable
- strict FIFO ordering
- dequeus with timeouts (called lease())
- embeddable
const Qool = require('qool')
const level = require('level-bytewise')
const db = level('db')
const queue = Qool.create(db)
queue.enqueue('a')
queue.enqueue('b', (err) => {})
queue.dequeue()
queue.dequeue((err, value) => {})Enqueue and Dequeue are batched under the hood, so callbacks are invoked synchronously. This means that you can only include a last callback and forgo all the others for Enqueues and Dequeues that happen in the same tick
const Qool = require('qool')
const level = require('level-bytewise')
const db = level('db')
const queue = Qool.create(db, 1000 * 10)
queue.enqueue('a')
queue.enqueue('b', (err) => {})
queue.lease((err, leaseKey, value) => {
// do something with the data
// delete the item permanently from the queue
queue.delete(leaseKey, (err) => {
})
})
// TBD
// lease with a non default timeout
//queue.leaseWithTimeout(1000 * 2, (err, leaseKey, value) => {})const Qool = require('qool')
const level = require('level-bytewise')
const db = level('db')
const queue = Qool.create(db)
queue.enqueue('a')
queue.enqueue('b', (err) => {})
queue.peek((err, value) => {
// value === 'a'
})
queue.peekMany((err, results) => {
// results === [{ key: ..., value: 'a' }, { key: ..., value: 'b' }]
})Some ramblings on internal design are here
- enhance tests
- implement length property
- should we have a version of dequeue that "waits" if the queue is empty
- expiry for enqueued items
MIT © yaniv kessler