Pubsubr NPM | npm.io

pubsubr

pub and sub to loopback

Installation

$ npm install --save pubsubr

Example Usage

server

const pubsubr = require('pubsubr');
const server = new pubsubr.server('mqtt://test.mosquitto.org', app.models.EventLog);

client

const pubsubr = require('pubsubr');
const client = new pubsubr.client('mqtt://test.mosquitto.org', 'http://0.0.0.0:3000/api/eventLog');

create model

创建EventLog模型，用于客户端重连或重新运行获取丢失的publish

⚠️注意：模型字段会解析topic和字段topic、message、createdAt、updatedAt组成对象存进数据库，所以topic配置需和model字段相匹配

loopback

从模块中使用已定义好的模型，配置model-config.json:

{
  "_meta": {
    "sources": [
      "loopback/common/models",
      "loopback/server/models",
      "../common/models",
      "./models",
      "pubsubr/models"
    ],
    "mixins": [
      "loopback/common/mixins",
      "loopback/server/mixins",
      "../common/mixins",
      "./mixins"
    ]
  },
  "EventLog": {
    "dataSource": "db",
    "public": true
  }
}

other

配置好模型，在创建server对象时传入

Topic

tipic的处理和格式,key/value形式，+为级别任意通配符，#为层级任意通配符

publish时，会解析topic成为object加上字段topic、message、createdAt、updatedAt存入数据库事件日志表，例如：uid/123456789/model/Account/oid/abcdefg/action/create解析为{uid: '123456789', model: 'Account', oid: 'abcdefg', action: 'create'}
subscribe时，可通过通配符监听，同样会把topic解析放入payload中传入handler

API

pubsubr

pubsubr.server(options, model)

create pubsubr server

options connect to mosquitto ro mosca, String: mqtt://test.mosquitto.org , Object: {host: 'localhost', port: '1883'}
model - EventLog，用于客户端重连或重新运行获取丢失的publish，会使用模型的create创建一条数据，为null不创建数据

pubsubr.client(options, api)

create pubsubr client

options connect to mosquitto ro mosca, String: mqtt://test.mosquitto.org , Object:
- host default localhost
- port default 1883
api 获取事件日志数据的api

server

server.publish(topic, message, options, callback)

Publish a message to a topic

topic is the topic to publish to, String
message is the message to publish,Object or String
options is the options to publish with, including:
- qos QoS level, Number, default 0
- retain retain flag, Boolean, default false
- dup mark as duplicate flag, Boolean, default false
callback - function (err), fired when the QoS handling completes, or at the next tick if QoS 0. An error occurs if client is disconnecting.

client

client.subscribe(topic, options, handler)

Subscribe to a topic or topics

topic is a String topic of subscribe to topics to subscribe to. It can also be an object, it has as object keys the topic name and as value the QoS, like {'test1': 0, 'test2': 1}. MQTT topic wildcard characters are supported (+ - for single level and # - for multi level)
options is the options to subscribe with, including:
- qos qos subscription level, default 0
- time 最后一次收到事件的时间，用于重新获取漏处理的事件，发生于客户端重起和mqtt服务断线重连的时候，重连暂时只支持loopback的REST API风格
callback - function (err, granted) callback fired on suback where:
- err a subscription error or an error that occurs when client is disconnecting
- granted is an array of {topic, qos} where:
  - topic is a subscribed to topic
  - qos is the granted qos level on it

unsubscribe(topic, callback)

Unsubscribe from a topic or topics

topic is a String topic or an array of topics to unsubscribe from
callback - function (err), fired on unsuback. An error occurs if client is disconnecting.