prisme-flow/nodes/bridge/redis/redisout.js

prisme platform flow engine

/**
 * Created by prisme.io on 09/06/2017.
 */
module.exports = function (RED) {
  'use strict'
  var redis = require('redis')

  var hashFieldRE = /^([^=]+)=(.*)$/

  var redisConnectionPool = (function () {
    var connections = {}
    var obj = {
      get: function (host, port) {
        var id = host + ':' + port
        if (!connections[id]) {
          connections[id] = redis.createClient(port, host)
          connections[id].on('error', function (err) {
            RED.log.error(err)
          })
          connections[id]._id = id
          connections[id]._nodeCount = 0
        }
        connections[id]._nodeCount += 1
        return connections[id]
      },
      close: function (connection) {
        connection._nodeCount -= 1
        if (connection._nodeCount === 0) {
          if (connection) {
            clearTimeout(connection.retry_timer)
            connection.end()
          }
          delete connections[connection._id]
        }
      }
    }
    return obj
  }())

  function RedisOutNode (n) {
    RED.nodes.createNode(this, n)
    this.port = n.port || '6379'
    this.hostname = n.hostname || '127.0.0.1'
    this.key = n.key
    this.structtype = n.structtype

    this.client = redisConnectionPool.get(this.hostname, this.port)

    if (this.client.connected) {
      this.status({fill: 'green', shape: 'dot', text: 'connected'})
    } else {
      this.status({fill: 'red', shape: 'ring', text: 'disconnected'}, true)
    }

    var node = this
    this.client.on('end', function () {
      node.status({fill: 'red', shape: 'ring', text: 'disconnected'})
    })
    this.client.on('connect', function () {
      node.status({fill: 'green', shape: 'dot', text: 'connected'})
    })

    this.on('input', function (msg) {
      var k = this.key || msg.topic
      if (k) {
        if (this.structtype == 'string') {
          this.client.set(k, RED.util.ensureString(msg.payload))
        } else if (this.structtype == 'hash') {
          if (typeof msg.payload === 'object') {
            this.client.hmset(k, msg.payload)
          } else {
            var r = hashFieldRE.exec(msg.payload)
            if (r) {
              this.client.hset(k, r[1], r[2])
            } else {
              this.warn(RED._('Invalid payload for redis hash'))
            }
          }
        } else if (this.structtype == 'set') {
          this.client.sadd(k, msg.payload)
        } else if (this.structtype == 'list') {
          this.client.rpush(k, msg.payload)
        }
      } else {
        this.warn(RED._('No key or topic set'))
      }
    })
    this.on('close', function () {
      redisConnectionPool.close(node.client)
    })
  }
  RED.nodes.registerType('redis out', RedisOutNode)
}