Node.js course notes

Basic node modules

To create a Node Module (in package.json). <Major Version>.<Minor Version>.<Patch>

To specify the acceptable package version:

Exact: npm install [email protected]
Patch acceptable: npm install express@"~4.0.0"
Minor version acceptable: npm install express@"^4.0.0"

## Node and HTTP

HTTP core module:
var http = require('http');
File system core module ():
var fs = require('fs');
Path core module: Make OS's independent paths
var path = require('path');

Express module

Express is a Web application framework that provides a robust set of features. To install it do: npm install express --save

Morgan is a logging modure that works with Express. To install morga do: npm install morgan --save Check ./node-express/server-2.js to see how to.

HTTP <-> REST equivalence:

HTTP GET -> READ
HTTP POST -> CREATE
HTTP PUT -> UPDATE
HTTP DELETE -> DELETE

###Express router

app.all('/dishes', function(req,ser,next){...});
app.get('/dishes', function(req,ser,next){...});
app.post('/dishes', function(req,ser,next){...});
app.put('/dishes', function(req,ser,next){...});
app.delete('/dishes', function(req,ser,next){...});

other way to do this

dishRouter.route('/')
	.all(...);
	.get(...);
	.post(...);
	.put(...);
	.delete(...);

app.get('/dishes/:dishId', function(req,ser,next){...}); With this we can use dishId as a variable.

To install body-parser npm install body-parser --save

##Express Generator To install Express generator type npm install express-generator -g Then express \<App name\> After that go to the folder and type npm install` to install the required modules.

##MongoDB Install mongo DB driver for NodeJS npm install mongodb --save To test for conditions: npm install assert --save

mongod --dbpath=../mongodb/data/ mongo node ...

##Mongoose ODM (object data model) npm install mongoose --save

##REST API with Express, MongoDB and Mongoose rest-server folder

##Basic Authentication Authorization is a String (username:password) encoded with Base64. "Authorization: Basic QWdhagsghghdsfghdfg==" basic-auth folder

##Cookies and Express Sessions As HTTP does not provide any method for User tracking, we should do it with Cookies or express-sesions.

Cookies: npm install cookie-parser basic-auth-cookies folder

Express sessions: sudo npm install express-session session-file-store --save basic-auth-session folder The session cookies are in basic-auth-session/sessions

##User Authentication with Passport npm install jsonwebtoken -save // to use JWT

###Passport module Authentication middleware for Node.js

Supports:

• Local strategy
• OpenID
• Oauth

npm install passport --save For local strategy npm install passport-local --save Plugin to simplify building user/pass login with MongoDB and mongoose npm install passport-local-mongoose --

##Mongoose Population NoSQL databases do not explicitly support relations lies the SLQ databases. (ie: join()).

Population is the process of automatically replace specified paths within a document with documents from another collection.

mongoose-population folder.

##HTTPS and Secure Communication https-rest-server-passport folder

##OAuth and Users Authentication OAuth-rest-server-passport folder

##Backend as a Service (BaaS) Advantages:

• Pre-built, tried and tested components
• Reducion in server-side development effort
• Recent technological developments integrated by the service provider and made accessible to developers.

Disadvantages:

• Black box
• Vendor lock-in
• Loss of flexibility
• Additional training needed in vendor-specific APIs

Exercise: npm install strongloop -g

slc loopback (and follow instructions) cd folder sudo npm install slc loopback:model (and define the atributes of a document) slc loopback:relation (to define relationships) [ie. to join dishes with comments]

Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:relation
? Select the model to create the relationship from: dishes
? Relation type: has many
? Choose a model to create a relationship with: Comments
? Enter the property name for the relation: comments
? Optionally enter a custom foreign key: 
? Require a through model? No
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:relation
? Select the model to create the relationship from: dishes
? Relation type: has many
? Choose a model to create a relationship with: Customer
? Enter the property name for the relation: customers
? Optionally enter a custom foreign key: 
? Require a through model? No
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:relation
? Select the model to create the relationship from: Comments
? Relation type: belongs to
? Choose a model to create a relationship with: dishes
? Enter the property name for the relation: dishes
? Optionally enter a custom foreign key: 
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:relation
? Select the model to create the relationship from: Comments
? Relation type: belongs to
? Choose a model to create a relationship with: Customer
? Enter the property name for the relation: customer
? Optionally enter a custom foreign key: customerId
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:relation
? Select the model to create the relationship from: Customer
? Relation type: has many
? Choose a model to create a relationship with: Comments
? Enter the property name for the relation: comments
? Optionally enter a custom foreign key: customerId
? Require a through model? No

[example. Define access permissions for Comments collection]

Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:acl
? Select the model to apply the ACL entry to: dishes
? Select the ACL scope: All methods and properties
? Select the access type: Write
? Select the role other
? Enter the role name: admin
? Select the permission to apply Explicitly grant access
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:acl
? Select the model to apply the ACL entry to: (all existing models)
? Select the ACL scope: All methods and properties
? Select the access type: All (match all types)
? Select the role All users
? Select the permission to apply Explicitly deny access
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:acl
? Select the model to apply the ACL entry to: Comments
? Select the ACL scope: All methods and properties
? Select the access type: Read
? Select the role Any authenticated user
? Select the permission to apply Explicitly grant access
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:acl
? Select the model to apply the ACL entry to: Comments
? Select the ACL scope: A single method
? Enter the method name create
? Select the role Any authenticated user
? Select the permission to apply Explicitly grant access
Enriques-MacBook-Pro:loopback-server Kike$ slc loopback:acl
? Select the model to apply the ACL entry to: Comments
? Select the ACL scope: All methods and properties
? Select the access type: Write
? Select the role The user owning the object
? Select the permission to apply Explicitly grant access
Enriques-MacBook-Pro:loopback-server Kike$ 

//Start server slc start (or node .)

##MongoDB commands show dbs use show collections db.collectionName.find() //show all the data in a collection db.collectionName.drop() //delete that collection { "username":"", "password":"" }