prisme-flow/nodes/bridge/snmp/snmp.js

prisme platform flow engine

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

  var sessions = {}

  function getSession (host, community, version) {
    var sessionKey = host + ':' + community + ':' + version
    if (!(sessionKey in sessions)) {
      sessions[sessionKey] = snmp.createSession(host, community, {version: version})
    }
    return sessions[sessionKey]
  }

  function SnmpNode (n) {
    RED.nodes.createNode(this, n)
    this.community = n.community
    this.host = n.host
    this.version = (n.version === '2c') ? snmp.Version2c : snmp.Version1
    this.oids = n.oids.replace(/\s/g, '')
    var node = this

    this.on('input', function (msg) {
      var host = node.host || msg.host
      var community = node.community || msg.community
      var oids = node.oids || msg.oid
      if (oids) {
        getSession(host, community, node.version).get(oids.split(','), function (error, varbinds) {
          if (error) {
            node.error(error.toString(), msg)
          } else {
            for (var i = 0; i < varbinds.length; i++) {
              if (snmp.isVarbindError(varbinds[i])) {
                node.error(snmp.varbindError(varbinds[i]), msg)
              } else {
                if (varbinds[i].type == 4) { varbinds[i].value = varbinds[i].value.toString() }
                varbinds[i].tstr = snmp.ObjectType[varbinds[i].type]
                                // node.log(varbinds[i].oid + "|" + varbinds[i].tstr + "|" + varbinds[i].value);
              }
            }
            msg.oid = oids
            msg.payload = varbinds
            node.send(msg)
          }
        })
      } else {
        node.warn('No oid(s) to search for')
      }
    })
  }
  RED.nodes.registerType('snmp', SnmpNode)

  function SnmpTNode (n) {
    RED.nodes.createNode(this, n)
    this.community = n.community
    this.host = n.host
    this.version = (n.version === '2c') ? snmp.Version2c : snmp.Version1
    this.oids = n.oids.replace(/\s/g, '')
    var node = this
    var maxRepetitions = 20

    function sortInt (a, b) {
      if (a > b) { return 1 } else if (b > a) { return -1 } else { return 0 }
    }

    this.on('input', function (msg) {
      var host = node.host || msg.host
      var community = node.community || msg.community
      var oids = node.oids || msg.oid
      if (oids) {
        msg.oid = oids
        getSession(host, community, node.version).table(oids, maxRepetitions, function (error, table) {
          if (error) {
            node.error(error.toString(), msg)
          } else {
            var indexes = []
            for (var index in table) {
              if (table.hasOwnProperty(index)) {
                indexes.push(parseInt(index))
              }
            }
            indexes.sort(sortInt)
            for (var i = 0; i < indexes.length; i++) {
              var columns = []
              for (var column in table[indexes[i]]) {
                if (table[indexes[i]].hasOwnProperty(column)) {
                  columns.push(parseInt(column))
                }
              }
              columns.sort(sortInt)
                            // console.log("row index = " + indexes[i]);
                            // for (var j = 0; j < columns.length; j++) {
                            //     console.log("  column " + columns[j] + " = " + table[indexes[i]][columns[j]]);
                            // }
            }
            msg.payload = table
            node.send(msg)
          }
        })
      } else {
        node.warn('No oid to search for')
      }
    })
  }
  RED.nodes.registerType('snmp table', SnmpTNode)

  function SnmpSubtreeNode (n) {
    RED.nodes.createNode(this, n)
    this.community = n.community
    this.host = n.host
    this.version = (n.version === '2c') ? snmp.Version2c : snmp.Version1
    this.oids = n.oids.replace(/\s/g, '')
    var node = this
    var maxRepetitions = 20
    var response = []

    function feedCb (varbinds) {
      for (var i = 0; i < varbinds.length; i++) {
        if (snmp.isVarbindError(varbinds[i])) {
          node.error(snmp.varbindError(varbinds[i]), msg)
        } else {
                    // console.log(varbinds[i].oid + "|" + varbinds[i].value);
          response.push({oid: varbinds[i].oid, value: varbinds[i].value})
        }
      }
    }

    this.on('input', function (msg) {
      var host = node.host || msg.host
      var community = node.community || msg.community
      var oids = node.oids || msg.oid
      if (oids) {
        msg.oid = oids
        getSession(host, community, node.version).subtree(msg.oid, maxRepetitions, feedCb, function (error) {
          if (error) {
            node.error(error.toString(), msg)
          } else {
            msg.payload = response
            node.send(msg)
                        // Clears response
            response.length = 0
          }
        })
      } else {
        node.warn('No oid to search for')
      }
    })
  }
  RED.nodes.registerType('snmp subtree', SnmpSubtreeNode)

  function SnmpWalkerNode (n) {
    RED.nodes.createNode(this, n)
    this.community = n.community
    this.host = n.host
    this.version = (n.version === '2c') ? snmp.Version2c : snmp.Version1
    this.oids = n.oids.replace(/\s/g, '')
    var node = this
    var maxRepetitions = 20
    var response = []

    function feedCb (varbinds) {
      for (var i = 0; i < varbinds.length; i++) {
        if (snmp.isVarbindError(varbinds[i])) {
          node.error(snmp.varbindError(varbinds[i]), msg)
        } else {
                    // console.log(varbinds[i].oid + "|" + varbinds[i].value);
          response.push({oid: varbinds[i].oid, value: varbinds[i].value})
        }
      }
    }

    this.on('input', function (msg) {
      node.msg = msg
      var oids = node.oids || msg.oid
      var host = node.host || msg.host
      var community = node.community || msg.community
      if (oids) {
        msg.oid = oids
        getSession(host, community, node.version).walk(msg.oid, maxRepetitions, feedCb, function (error) {
          if (error) {
            node.error(error.toString(), msg)
          } else {
            msg.payload = response
            node.send(msg)
                        // Clears response
            response.length = 0
          }
        })
      } else {
        node.warn('No oid to search for')
      }
    })
  }
  RED.nodes.registerType('snmp walker', SnmpWalkerNode)
}