find query in mongodb don't return data

Question

I know it's a very basic question but here is the problem. I'm following the doc.

I'm using mongodb, express and node.

I have a collection users with users data. I want to have a json of all users when I go on the url '/';

var users;
MongoClient.connect("mongodb://localhost:27017/test", function(err, db) {
  if(err) { return console.dir(err); }
  users = db.collection('users');
});


app.get('/', function (req, res) {
  users.find({}, function (err, docs) {
    res.send(JSON.stringify(docs));
  });
});

but the docs objects contains lot of thing but not all users. How do I get all users?

Readable {
  connection: null,
  server: null,
  disconnectHandler: 
   { s: { storedOps: [], storeOptions: [Object], topology: [Object] },
     length: [Getter] },
  bson: {},
  ns: 'test.users',
  cmd: 
   { find: 'test.users',
     limit: 0,
     skip: 0,
     query: {},
     slaveOk: true,
     readPreference: { preference: 'primary', tags: undefined, options: undefined } },
  options: 
   { skip: 0,
     limit: 0,
     raw: undefined,
     hint: null,
     timeout: undefined,
     slaveOk: true,
     readPreference: { preference: 'primary', tags: undefined, options: undefined },
     db: 
      EventEmitter {
        domain: null,
        _events: {},
        _eventsCount: 0,
        _maxListeners: undefined,
        s: [Object],
        serverConfig: [Getter],
        bufferMaxEntries: [Getter],
        databaseName: [Getter],
        options: [Getter],
        native_parser: [Getter],
        slaveOk: [Getter],
        writeConcern: [Getter] },
     promiseLibrary: [Function: Promise],
     disconnectHandler: { s: [Object], length: [Getter] } },
  topology: 
   EventEmitter {
     domain: null,
     _events: 
      { reconnect: [Function],
        timeout: [Object],
        error: [Object],
        close: [Function],
        destroy: [Object] },
     _eventsCount: 5,
     _maxListeners: undefined,
     s: 
      { options: [Object],
        callbacks: [Object],
        logger: [Object],
        state: 'connected',
        reconnect: true,
        reconnectTries: 30,
        reconnectInterval: 1000,
        emitError: true,
        currentReconnectRetry: 30,
        ismaster: [Object],
        readPreferenceStrategies: undefined,
        authProviders: [Object],
        id: 1,
        tag: undefined,
        disconnectHandler: [Object],
        wireProtocolHandler: {},
        Cursor: [Object],
        bsonInstance: {},
        bson: {},
        pool: [Object],
        serverDetails: [Object] },
     name: [Getter],
     bson: [Getter],
     wireProtocolHandler: [Getter],
     id: [Getter] },
  cursorState: 
   { cursorId: null,
     cmd: 
      { find: 'test.users',
        limit: 0,
        skip: 0,
        query: {},
        slaveOk: true,
        readPreference: [Object] },
     documents: [],
     cursorIndex: 0,
     dead: false,
     killed: false,
     init: false,
     notified: false,
     limit: 0,
     skip: 0,
     batchSize: 1000,
     currentLimit: 0,
     transforms: undefined },
  callbacks: null,
  logger: { className: 'Cursor' },
  _readableState: 
   ReadableState {
     objectMode: true,
     highWaterMark: 16,
     buffer: [],
     length: 0,
     pipes: null,
     pipesCount: 0,
     flowing: null,
     ended: false,
     endEmitted: false,
     reading: false,
     sync: true,
     needReadable: false,
     emittedReadable: false,
     readableListening: false,
     defaultEncoding: 'utf8',
     ranOut: false,
     awaitDrain: 0,
     readingMore: false,
     decoder: null,
     encoding: null },
  readable: true,
  domain: null,
  _events: {},
  _eventsCount: 0,
  _maxListeners: undefined,
  s: 
   { numberOfRetries: 5,
     tailableRetryInterval: 500,
     currentNumberOfRetries: 5,
     state: 0,
     streamOptions: {},
     bson: {},
     ns: 'test.users',
     cmd: 
      { find: 'test.users',
        limit: 0,
        skip: 0,
        query: {},
        slaveOk: true,
        readPreference: [Object] },
     options: 
      { skip: 0,
        limit: 0,
        raw: undefined,
        hint: null,
        timeout: undefined,
        slaveOk: true,
        readPreference: [Object],
        db: [Object],
        promiseLibrary: [Function: Promise],
        disconnectHandler: [Object] },
     topology: 
      EventEmitter {
        domain: null,
        _events: [Object],
        _eventsCount: 5,
        _maxListeners: undefined,
        s: [Object],
        name: [Getter],
        bson: [Getter],
        wireProtocolHandler: [Getter],
        id: [Getter] },
     topologyOptions: 
      { socketOptions: {},
        auto_reconnect: true,
        host: 'localhost',
        port: 27017,
        cursorFactory: [Object],
        reconnect: true,
        emitError: true,
        size: 5,
        disconnectHandler: [Object],
        bson: {},
        messageHandler: [Function],
        wireProtocolHandler: {} },
     promiseLibrary: [Function: Promise],
     currentDoc: null },
  timeout: false,
  sortValue: undefined,
  readPreference: { preference: 'primary', tags: undefined, options: undefined } }

Answer 1

With the mongodb module you are using

when you do .find it will return you a cursor, and with the cursor you can loop cursor.each but what you want to do most of the cases is to transform it into an array.

users.find({}).toArray(function(err, results){
    console.log(results);
});

This is the doc stating what I just wrote: https://mongodb.github.io/node-mongodb-native/markdown-docs/queries.html#making-queries-with-find