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JavaScript Build a REST API With Express Modeling Data for the API Connecting Mongoose to MongoDB

Posted by Richard Brown
Richard Brown
6,950 Points

TypeError: Schema is not a constructor

Hi all.

I wonder if someone can help me, please. :)

Here's my code: 

'use strict'
var mongoose = require("mongoose");

mongoose.connect("mongodb://localhost:27017/sandbox");

var db = mongoose.connection;

db.on("error", function(error){
    console.log("connection error:", err);
});

db.once("open", function(){
    console.log("database connection successful");
    // all database communication goes here

    var Schema = new mongoose.Schema;
    var AnimalSchema = new Schema({
        type: String,
        color: String,
        size: String,
        mass: Number,
        name: String
    });

    var Animal = mongoose.model("Animal", AnimalSchema);

    var elephant = new Animal({
        type: "elephant",
        size: "big",
        color: "grey",
        mass: 6000,
        name: "Lawerence"
    });

    elephant.save(function(err){
        if(err) console.log("saved failed.");
        else console.log("saved");
        db.close(function(){
            console.log("connection closed.");
        });
    });

});

And here's the console: 

$ node mongoose_sandbox.js
database connection successful
TypeError: Schema is not a constructor
    at NativeConnection.<anonymous> (C:\TreeHouse\rest-api\mongoose_sandbox.js:17:24)
    at Object.onceWrapper (events.js:313:30)
    at emitNone (events.js:106:13)
    at NativeConnection.emit (events.js:208:7)
    at open (C:\TreeHouse\rest-api\node_modules\mongoose\lib\connection.js:512:11)
    at NativeConnection.Connection.onOpen (C:\TreeHouse\rest-api\node_modules\mongoose\lib\connection.js:521:5)
    at C:\TreeHouse\rest-api\node_modules\mongoose\lib\connection.js:483:11
    at C:\TreeHouse\rest-api\node_modules\mongoose\lib\drivers\node-mongodb-native\connection.js:60:5
    at C:\TreeHouse\rest-api\node_modules\mongodb\lib\db.js:234:5
    at Server.connectHandler (C:\TreeHouse\rest-api\node_modules\mongodb\lib\server.js:306:7)
    at Object.onceWrapper (events.js:315:30)
    at emitOne (events.js:116:13)
    at Server.emit (events.js:211:7)
    at C:\TreeHouse\rest-api\node_modules\mongodb-core\lib\topologies\server.js:572:23
    at C:\TreeHouse\rest-api\node_modules\mongodb-core\lib\topologies\server.js:492:18
    at ScramSHA1.reauthenticate (C:\TreeHouse\rest-api\node_modules\mongodb-core\lib\auth\scram.js:312:25)
C:\TreeHouse\rest-api\node_modules\mongodb\lib\server.js:309
      process.nextTick(function() { throw err; })

Any suggestions?

Thanks in advance.

2 Answers

Rich Donnellan
MOD
Rich Donnellan
Treehouse Moderator 27,696 Points
Rich Donnellan
Rich Donnellan
Treehouse Moderator 27,696 Points

Check this line:

var Schema = new mongoose.Schema;

Removing the new should do the trick.

Richard Brown
Richard Brown
6,950 Points
Richard Brown
Richard Brown
6,950 Points

Thank you so much for your prompt reply.. A feel a 'doh!' coming on! :)