MongoDB and NodeJs
MongoDB
NodeJs
Installation
We will install :
- MongoDb
- Node
- Robomongo - editor
brew - package manager can be used on MacOs
/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"Mongo Installation:
>brew install mongo
>mongod
>sudo mkdir -p /data/db
>sudo chown -Rv rasimsen /data/db
>brew services start mongo #start/stop/statusNodeJs-Mongo
Create a project
$ mkdir users => cd users
$ mkdir src
$ mkdir test$ npm install request --save #url için
$ npm install --save mocha nodemon mongoosemocha: unit test nodemon: mongoose : mongo db driver
src/user.js:
const mongoose=require('mongoose');
const Schema=mongoose.Schema;
const UserSchema = new Schema({
name:String
});
const User = mongoose.model('User',UserSchema);
module.exports = User;
package.json - project details and depencies file
package.json file:
{
"name": "users",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"test": "mocha"
},
"author": "",
"license": "ISC",
"dependencies": {
"mocha": "^5.2.0",
"mongoose": "^5.3.10",
"nodemon": "^1.18.6",
"request": "^2.88.0"
}
}
Mocha - Unit Test
Mocha is most famous test framework for javascript..
Creating data on MongoDb/Test
test/create_test.js(test file):
const assert = require('assert');
describe('Creating records',()=>{
it('saves a user',()=>{
assert(1+1 ===2);
});
});
test/create_test.js(another sample):
const assert = require('assert');
const User = require('../src/user');
describe('Creating records',()=>{
it('saves a user',(done)=>{ //<------------ 1.callback
const joe = new User({ name: 'Joe'});
//joe.save();
joe.save()
.then((result) => {
//Has joe been saved successfully?
assert(!joe.isNew);
done(); //<------------------- 2.callback: we should use
}).catch((err) => {
console.log('Error');
});
});
});
Search/Find Record on Mongo
reading_test.js:
const assert = require('assert');
const User = require('../src/user');
describe('Reading users out of the database', ()=>{
let joe;
beforeEach((done)=>{
joe=new User({name:'Joe'});
joe.save()
.then((result) => {
done();
}).catch((err) => {
console.log('Error..');
});
});
it('finds all users with a name of joe',(done)=>{
User.find({ name:'Joe' })
.then((users)=>{
console.log(users);
assert(users[0]._id.toString() === joe._id.toString());
done();
});
});
it('find a user with a particular id', (done)=>{
User.findOne({_id:joe._id})
.then((user)=>{
assert(user.name === 'Joe');
done();
});
});
});
Deleting/removing records
delete_test.js
const assert = require('assert');
const User = require('../src/user');
describe('Deleting a user',()=>{
let joe;
beforeEach((done)=>{
joe = new User({name:'Joe'});
joe.save()
.then((result) => {
done();
}).catch((err) => {
console.log('delete:error in beforeEach!');
});
});
it('model instance remove',(done)=>{
joe.remove()//it remove joe instance that we created in beforeEach method
.then(() => User.findOne({name:'Joe'}))//to test that the object deleted, it should return null
.then((user)=>{//then: they work sequentially
assert(user === null);
done();
})
;
});
it('class method remove',(done)=>{
//remove a bunch of records with some given criteria
User.remove({ name:'Joe' })
.then(()=>User.findOne({name:'Joe'}))
.then((user)=>{
assert(user === null);
done();
});
});
it('class method findAndRemove',(done)=>{
User.findOneAndRemove({name:'Joe'})
.then(()=>User.findOne({name:'Joe'}))
.then((user)=>{
assert(user === null);
done();
});
});
it('class method findByIdAndRemove',(done)=>{
User.findByIdAndRemove(joe._id)
.then(()=>User.findOne({name:'Joe'}))
.then((user)=>{
assert(user === null);
done();
});
});
});
Updating records
update_test.js:
const assert=require('assert');
const User = require('../src/user');
describe('Updating records',()=>{
let joe;
beforeEach((done)=>{
joe = new User({name:'Joe'});
joe.save()
.then(()=>done());
});
function assertName(operation, done){
operation
.then(()=>User.find({}))
.then((users)=>{
assert(users.length === 1);
assert(users[0].name === 'Alex');
done();
});
}
//set and save: when you update more record(emaıl, phone, address),
//like a transactional update,
//we can update all data, and then save all.
it('instance type using set n save',(done)=>{
console.log(joe);
joe.set('name','Alex');
assertName(joe.save(),done);
console.log(joe);
});
//update : directly update
it('A model instance can update',(done)=>{
assertName(joe.update({name:'Alex'}),done);
});
it('A model class can update', (done)=>{
assertName(
User.update({name:'Joe',name:'Alex'}),
done
);
});
it('A model class can update one record', (done)=>{
assertName(
User.findOneAndUpdate({name:'Joe',name:'Alex'}),
done
);
});
it('A model class can find a record with an Id and update',(done)=>{
assertName(
User.findByIdAndUpdate(joe._id,{name:'Alex'}),
done
);
});
});
Run the test : npm run test
$ npm run testAutomating Test
"test": "nodemon --exec 'mocha -R min'" : formats and clear the output
If I change the code, it runs test again for changes.
{
"name": "users",
"version": "1.0.0",
"description": "",
"main": "index.js",
"scripts": {
"test": "nodemon --exec 'mocha -R min'"
},
"author": "",
"license": "ISC",
"dependencies": {
"mocha": "^5.2.0",
"mongoose": "^5.3.10",
"nodemon": "^1.18.6",
"request": "^2.88.0"
}
}
Errors
(node:27919) DeprecationWarning: current URL string parser is deprecated, and will be removed in a future version. To use the new parser, pass option { useNewUrlParser: true } to MongoClient.connect.Solution: Check your mongo version
mongo --version
If you are using version >= 3.1.0 change you mongo connection file to ->
MongoClient.connect("mongodb://localhost:27017/YourDB", { useNewUrlParser: true })
or your mongoose connection file to ->
mongoose.connect("mongodb://localhost:27017/YourDB", { useNewUrlParser: true });
Ideally, it's a version 4 feature but v3.1.0 and above is supporting it too. Check out MongoDB Github for details.Error: TypeError: User is not a constructor Solution: Node is a case-sensetive language. Check your model or object..
