nmpriq

Priority queue service based on HTTP with Node.js and MongoDB backend

About

Nmpriq is a priority queue service which is able to use simple by HTTP protocol.

Prerequisites

• Node.js
• MongoDB

How to use

Install

$ git clone https://github.com/tilfin/nmpriq.git
$ cd nmpriq
$ npm install

Usage

$ ./bin/nmpriq --help
Usage: nmpriq [options] <MongoDB URI>

Options:

  -h, --help      output usage information
  -V, --version   output the version number
  -p, --port <n>  listening port

Enqueue and Dequeue

HTTP POST is enqueue. HTTP GET is dequeue. The 'key' is main item key. 'queueName' is mongodb collection name.

$ curl -X POST \
    -H 'Content-Type: application/json' \
    -d '{"key":"item1"}' \
    http://localhost:<port>/<queueName>
{"message":"success"}


$ curl -X GET http://localhost:<port>/<queueName>
{"key":"item1","priority":10}

If a client requests GET when the queue is emtpy, nmpriq server accepts its GET as long-polling. Receiving new item by other clients, the server immediately returns it.

Use priority

The dequeue order is higher priority and enqueued order. A default prority is 10.

'item1' is enqueued first with defalut prority.

$ curl -X POST \
    -H 'Content-Type: application/json' \
    -d '{"key":"item1"}' \
    http://localhost:<port>/<queueName>
{"message":"success"}

'item2' is enqueued second with prority is 50.

$ curl -X POST \
    -H 'Content-Type: application/json' \
    -d '{"key":"item2","prority":50}' \
    http://localhost:<port>/<queueName>
{"message":"success"}



$ curl -X GET http://localhost:<port>/<queueName>
{"key":"item2","priority":50}

'item2' is dequeued.

$ curl -X GET http://localhost:<port>/<queueName>
{"key":"item1","priority":10}

'item1' is dequeued.

Priority addition

If an item has already enqueued, its priority is added.

$ curl -X POST \
    -H 'Content-Type: application/json' \
    -d '{"key":"item1"}' \
    http://localhost:<port>/<queueName>
{"message":"success"}

item1's priority is 10.

$ curl -X POST \
    -H 'Content-Type: application/json' \
    -d '{"key":"item1","prority":20}' \
    http://localhost:<port>/<queueName>
{"message":"success"}

item1's priority is added 20.

$ curl -X GET http://localhost:<port>/<queueName>
{"key":"item1","priority":30}

item1's priority is 30.

With custom values

The 'value' is custom value field. It is stored as a part of mongodb document.

$ curl -X POST \
    -H 'Content-Type: application/json' \
    -d '{"key":"item1","value":{"name":"taro","age":25}}' \
    http://localhost:<port>/<queueName>
{"message":"success"}


$ curl -X GET http://localhost:<port>/<queueName>
{"key":"item1","priority":10,"value":{"name":"taro","age":25}}