mongodb.org

install

sudo pacman -S mongodb
sudo systemctl enable mongodb.service
sudo systemctl start mongodb.service

mongo shell

mongo

Definitions

mongo	sql
collection	table
document	record

insert document into collection

Insert a record (document) into a table called userlist

db.userlist.insert({'username' : 'test1', 'email' : 'test1@test.com', 'gender' : 'Male'})

remove a collection

To empty the userlist collection do:

db.userlist.remove()

drop whole database

db.dropDatabase()

show all databases

show dbs

show all tables/collections

show collections

bulk load a JSON file

from command line, NOT MONGO SHELL!!!

json file	data.js
collection	people
database	simple

$ mongoimport --db simple --collection people --jsonArray data.js

get documents from collection

collection: posts

db.posts.find()

Setup REST

Express

npm install -g express-generator

Now lets say our project is going to be called: abc123, scaffold it out with:

express --ejs abc123
cd abc123; npm install

Mongoose

Tell node/express that we want to use mongoose as our javascript library to interact with MongoDB.

npm install --save mongoose

To connect to a database called test, in app.js put:

var mongoose = require('mongoose');
mongoose.connect('mongodb://localhost/test');

TEST you can now test the connection by seeing if starting node throws any errors

npm start

Model

Now lets create a model called Posts which holds blog posts. Lets create a folder to hold our models

mkdir Models 

Here create the file Posts.js with the following contents:

var mongoose = require('mongoose');
var PostSchema = new mongoose.Schema({
  title: String,
  body: String,
  upvotes: {type: Number, default: 0},
});
mongoose.model('Post', PostSchema);

REST

Now we want to interact with this model via REST. We will setup routes for the GET action.

routes/index.js

var mongoose = require('mongoose');
var Post = mongoose.model('Post');
router.get('/posts', function(req, res, next) {
  Post.find(function(err, posts){
    if(err){ return next(err); }
    res.json(posts);
  });
});

Wire routes to REST api

In app.js we need to declare the Posts schema/model before it is used in the routes:

require('./models/Posts');
var routes = require('./routes/index');  

TEST: Now we can test!

Start Node

npm start

Insert a post via mongodb shell

$ mongo
> db.posts.insert({'title' : 'test title', 'body' : 'This is the body.', 'upvotes': 0})

Query all posts with CURL

curl http://localhost:3000/posts

add POST verb

router/index.js

router.post('/posts', function(req, res, next) {
  var post = new Post(req.body);
  post.save(function(err, post){
    if(err){ return next(err); }
    res.json(post);
  });
});

TEST: Insert doc with CURL

curl --data 'short_description=Kensignton32GBUSB3.0Thumbdrive&price=500' http://localhost:3000/posts