Learn Elixir, Jwt and Serverless

Starting from a prebuilt frontend, Jason Lengstorf guides you through the creation of a "Corgi Up-boop App" that uses Netlify Functions and Hasura. You can view [the deployed final product on Netlify](https://egghead-serverless-functions.netlify.app/).

You'll set up the Netlify CLI, and configure a local development environment before writing and deploying functions with a few different use cases.

The first example function bypasses CORS restrictions to retrieve corgi data from an example third-party API.

Next, you'll configure environmental variables to securely communicate with the Unsplash API without exposing private keys to the client.

Serverless functions don't persist data by themselves, so we will use  Hasura to create a GraphQL API for tracking the number of "boops" each corgi receives.

This course is an excellent illustration of the speed of Serverless functions, and how fast you can implement functionality in your web applications.

An all-in-one workflow that combines global deployment, continuous integration, and automatic HTTPS.

netlify

Build a Corgi Up-boop Web App with Netlify Serverless Functions and Hasura

This playlist will be a smorgasbord of Auth0 authentication and authorization topics. Everything from adding Auth0 to various apps, customizing your Auth0 settings, adding specific rules / audiences / features, and debugging errors. 

JavaScript® (often shortened to JS) is a lightweight, interpreted, object-oriented language with first-class functions, most known as the scripting language for Web pages, but used in many non-browser environments as well such as node.js or Apache CouchDB. It is a prototype-based, multi-paradigm scripting language that is dynamic, and supports object-oriented, imperative, and functional programming styles.

javascript

Auth0 Tips and Tricks 

These videos include the introductory steps to writing your first Elixir function and beginning to understand some key concepts in Elixir that make it unique. 

Some of those concepts include:
- the Mix build tool
- project structure
- collections of functions written in modules
- function *arity*
- pattern matching and common uses for it
- the pipe operator

Elixir is a dynamic, functional language designed for building scalable and maintainable applications.

Elixir leverages the Erlang VM, known for running low-latency, distributed and fault-tolerant systems, while also being successfully used in web development and the embedded software domain.

elixir

Getting Started with Elixir

JSON Web Token (JWT) is a low overhead option for authentication that is easy to implement and scales with your application. There is no need to store session data as everything you need is stored in an encoded string sent in the JWT, significantly reducing database overhead for your servers.

In this course, we will build a simple authentication server that will act as a token issuer, and we will use those tokens to access resources on an API.  Starting from scratch, you will learn how easy token based authentication can be and will understand how to use them on your APIs as well as on the front end of your web applications.

Express is a minimal and flexible Node.js web application framework that provides a robust set of features for web and mobile applications.

express

JSON Web Token (JWT) Authentication with Node.js and Auth0

Create a serverless application and deploy it in under thirty minutes!

We'll be using Netlify, Vite, TypeScript, and React in our project. This stack synergizes extremely well for rapidly developing professional-quality applications. 

If you haven't heard of Vite, it's the French word for quick! It's also a build tool that consists of a dev-server and an extremely fast bundler. It makes for a rapid development loop.

As for the rest. Netlify makes hosting fast and easy with serverless functions and continuous deployment. React enables you to quickly create reusable components. And TypeScript helps you write cleaner code that is easier to refactor. 

So get started and learn how to use this stack in your own applications!

Create a TypeScript powered serverless React application

JSON Web Tokens (JWT) are a more modern approach to authentication. As the web moves to a greater separation between the client and server, JWT provides a terrific alternative to traditional cookie based authentication models. For more information on JWT visit http://jwt.io/

In this series, we’ll be building a simple application to get random user information from a node server with an Angular client. We’ll then implement JWT to protect the random user resource on the server and then work through the frontend to get JWT authentication working.

By the end, we’ll have an application which has a single username/password combination (for simplicity) and uses tokens to authorize the client to see the random user information. You’ll be able to login, get random users, and logout.

AngularJS is an open-source JavaScript framework, maintained by Google, that assists with running single-page applications. Its goal is to augment web-based applications with model–view–controller (MVC) capability, in an effort to make both development and testing easier.

angularjs

AngularJS Authentication with JWT

Adding middleware to the node server to decode and verify the token sent from the client. And tidying up the rest of the application. Finally, a walkthrough of the whole process.

Finalizing JWT Authentication with AngularJS

Creating the basic node server to serve up random users via API endpoints.

Basic Server Setup for JWT Authentication

Adding JWT support to the client. Storing the token in local storage, then creating a http interceptor to add the token to requests made to the server. Also implementing logout.


Auth Interceptor in Angular for JWT

A basic introduction to the mechanics of JWTs and the application we will be building in this lesson series.

JSON Web Token (JWT) Introduction

Adding JWT support to the server. Signing a JSON object as a payload and sending the signed token to the browser on authentication.

Server JWT Authentication Setup

JSON Web Tokens are an open, industry standard RFC 7519 method for representing claims securely between two parties.

In this lesson we will look at all of the pieces that combine together to create a JWT (j AWT) or JSON Web Token. You will use node to create a JWT, and then verify it in the JWT debugger.

Creating JWTs (JSON Web Tokens) in Node

Setting up a login on the angular app and an authentication endpoint on the server.

JWT Authentication Setup

Creating a basic Angular application to access the random users resource. Also setting up CORS on the node server to enable the resource sharing across different domains (ports in our case).

Client Setup for JWT Authentication

This lesson will digitally sign the IBM Domino user information into a JWT which can then be sent from the server to the client.

This JWT can then be sent back from the client to the server and the role information within the JWT file can be decrypted to determine a users level of functional access.

Encrypt IBM Domino User Roles Data into a JWT in a Express Application

This lesson will take the JWT sent from Express and store it in the browser local storage.  It will then resend the JWT back to the Express server when a HTTP call is made for additional IBM Domino Data.

This stateless method allows the server to trust what user roles the logged in user has to restrict what Express routes the user can call.  For instance you might want to restrict all Admin routes to only users which have the Admin role in the Domino ACL.

Send JWT Encrypted User Role Data from Client Local Storage to Express Server

This lesson will extract the JWT from the authorisation HTTP header and then decode it with the secret.

It will then check to make sure it contains a specific user role value to determine if a specific route can be called in Express.

Decode and Verify JWT Encoded Data in Express

The pipe operator is an easy to use and powerful feature of Elixir. It takes the output from the expression on the left, and automatically passes it as the first argument to the function on the right. This is especially useful when chaining together multiple function calls or data transformations. Using the pipe operator results in code that's easier to read, write and refactor.

Chain Function Calls with the Pipe Operator in Elixir

Elixir code is organized into groups of functions called modules. You can create your own modules and built on top of predefined modules that are a part of Elixir by default.

Additional resources: 
- [Getting started with Modules and function from Elixir docs](https://elixir-lang.org/getting-started/modules-and-functions.html)

Write a New Function Inside of an Elixir Module

Bootstrap a new Elixir project using Mix (a build tool included when you install Elixir), with its built in project generation.

Additional resources:
- [Official introduction to Mix](https://elixir-lang.org/getting-started/mix-otp/introduction-to-mix.html#our-first-project)

Generate a new Elixir project using Mix

The syntax to pass arguments into functions is akin to many other languages. Elixir functions are uniquely recognized when running based off of the number of arguments passed in (a term called *arity*). This means you can define functions with the same name, so long as a different number of arguments is passed in.

Arity is a key concept to be aware of when reading documentation and writing your own code.

Additional resources:
- [Information about arity](https://elixir-lang.org/getting-started/modules-and-functions.html#function-capturing)
- [Default arguments in functions](https://elixir-lang.org/getting-started/modules-and-functions.html#default-arguments)