javascript - Can two servers access a common mongoDB database -

i have 2 webservers have created on ports 3000 , 4000. 1 of webservers created database , has 3 collections..

show dbs local 0.000gb sensor_db 0.000gb use sensor_db switched db sensor_db show collections sensors templategroups templates

can 2nd server access database created ? if yes, not able access collections ..is there syntax it?

1st server:

var express = require('express'); var app= express(); var path = require('path'); var bodyparser= require('body-parser');  var mongoose = require('mongoose'); mongoose.connect('mongodb://localhost/sensor_db'); var schema = mongoose.schema;  var sensorschema = new schema({   value:{ type:number, default:0},   format:{type:string, default:"default"},   id:{type:number,required:true,unique:true},   description:{type:string},   type:{type:string},   groupid:{type:number},   users:{type:array,default:[]},   admin:{type:string,default:'undefined'},   status:{type:string,default:'undefined'},   owner:{type:string,default:'undefined'},   templateid:{type:number}  }); var sensor = mongoose.model('sensor',sensorschema);  app.get('/sensorlist',function(req,res) {   console.log("i recieved /sensorlist request");   sensor.find(function(err,data){     if (err) return console.error(err);     console.log(data);     res.json(data)   }); });  app.post('/check/health',function(req,res){   socket.emit('data', 'i need health status', function ack(data) {     console.log('data emit acknowledged monitoring server:', data);     return res.json(data);   }); }); 

2nd server:

var app = require('express')(); var server = require('http').server(app); var io = require('socket.io')(server); var express = require('express');  io.on('connection', function(socket){   console.log('connection received provisioning');    // messages provisioning server   socket.on('data', function(data, ack) {     console.log('message provision : ' + ': ' + data);     ack('here data - 1111');     console.log("trying access sensor_db database");      sensor.find(function(err,data){       if(err) return console.error(err);       console.log(data);       //res.json(data);     });   }); });  server.listen(4000, function(){   console.log('socket.io server listening on *:4000'); }); 

i error - sensor not defined

much jessi

i tried dispay collections once connected db error message : cannot read property 'haslistcollectionscommand' of null

var mongoose = require('mongoose'); mongoose.connect('mongodb://127.0.0.1:27017/sensor_db') ;     console.log("successfully connected database"); //mongoose.connection.db mongoose.connection.db.listcollections().toarray(function(err, names) {   if (err) {     console.log(err);   }   else {     names.foreach(function(e,i,a) {       mongoose.connection.db.dropcollection(e.name);       console.log("--->>", e.name);     });   } }); 

two different servers cannot share same instance of sensor object.

  var mongoose = require('mongoose');   mongoose.connect('mongodb://localhost/sensor_db');   var schema = mongoose.schema;  var sensorschema = new schema({   value:{ type:number, default:0},   format:{type:string, default:"default"},   id:{type:number,required:true,unique:true},   description:{type:string},   type:{type:string},   groupid:{type:number},   users:{type:array,default:[]},   admin:{type:string,default:'undefined'},   status:{type:string,default:'undefined'},   owner:{type:string,default:'undefined'},   templateid:{type:number}    }); var sensor = mongoose.model('sensor',sensorschema); 

this code declaring schema 1 server not second . have declare instance in second server also.

issue not mongo data base issue sensor instance not have declaration in second server.