title	author	geometry	output	urlcolor
SSAD	Tutorial 2	margin=3cm	pdf_document	blue

About the assignment

• The goal is to build a fully functional web application using Go and React along with RESTful API.
• The question is the same as last year's assignment. You can take a look at some of last year's works to see what the expected output is supposed to look like.
• Since this is a much bigger assignment than the last one, please start ASAP. The deadline is a hard one, and won't be extended. Don't wait till the last minute to start working on it.
• Question sufficiently explains all the requirements.

Go

Setting up

• For Ubuntu: Look here
• For MacOS: Look here
• Apart from above tutorial, add the following to your .bashrc:

              export GOBIN=$GOPATH/bin

• All your code (across projects) goes into one folder. So have your environment variables set up specific to where your code is.
• bin stores executables, pkg stores external packages, src has all your source code.

Basics

• The documentation is very well written. You're all advised to go through it.
• The Golang book is an absolute must for you to understand the fundamentals of Go.
• Similar to C
• All referred code is up on this repository.
• Hello world program
• Defining packages
  • Functions inside a package must start with a capital letter. Or else they won't be accessible outside the package.
  • Each package must consist of a directory along with a .go file of the same name inside the directory.
• Installing third party packages; use go get. An example:-

        go get -u -v gopkg.in/mgo.v2

• Packages used in this tutorial -

              go get -u -v github.com/gin-gonic/gin
              go get -u -v github.com/jinzhu/gorm
              go get -u -v github.com/jinzhu/gorm/dialects/sqlite
              go get -u -v github.com/gin-contrib/cors

• To run a program:-

              go run file.go

Building the server

• Setting up a server using gin
• Gin documentation is exhaustive, should resolve any doubts.
• Using an ORM with SQLite3
• A fully functional CRUD API
• Testing:-

              # Creating person
              curl -i -X POST http://localhost:8080/people -d '{ "FirstName": "Elvis", "LastName": "Presley"}'

              # Listing persons
              curl -X GET http://localhost:8080/people/

              # List only specific person
              curl -X GET http://localhost:8080/people/1

              # Delete specific user
              curl -i -X DELETE http://localhost:8080/people/1

              # Editing specific row
              curl -i -X PUT http://localhost:8080/people/2 -d '{ "city": "Hyd" }'

• The documentation for gorm is really helpful.
• If you want a more detailed explanation, look here
• For login/sign up using a simple HTTP server, look here. This is not very nice since it stores passwords as text. Find a way to hash it with a salt.
• To use Auth0 for all your authentication needs, look here

Advanced

• Optional for the assignment but nonetheless important for real world application
• What is Docker?
• Deploying server to Docker
• Go version manager is an alternative to manage isolated workspaces, but not very popular.

React

Setting up

• First, install node. Then install yarn (because npm is not very nice)
• Ubuntu:

              curl -sL https://deb.nodesource.com/setup_10.x | sudo -E bash -
              sudo apt-get install -y nodejs
              npm install -g yarn
              yarn global add create-react-app

• MacOS:

              brew install node
              npm install -g yarn
              yarn global add create-react-app

• Then, create a new React application by running the following:

              create-react-app name_of_app

• You can run the app by running yarn start
• node_modules contains all your external packages.
• package.json is a json file that contains all the environment requirements of your project. It is similar to the requirements.txt file we saw for python.
• public stores some static content. The index.html file is going to render whatever code you write. You will need to change that based on your application's design.
• bash yarn build builds your code into a production ready application. The contents are stored in the build directory.
• src contains all of your code. This should follow a good directory structure. Read more into it over here.
• Alternate structure to follow can be found here

Basics

• You can go through this tutorial for further details. You can ignore the setup part since the create-react-app model takes care of all dependencies and dev-dependencies.
• Prerequisites - HTML5, Javascript, CSS
• React supports ES7 syntax. ES is basically a standard for programming languages, created to standardise JS. What you learnt as JS is ES5. ES7 is backwards compatible, so you can continue to use ES5 in React, but obviously it's a lot more useful to use ES7.
• JSX - JSX is JavaScript syntax extension. Looks almost like HTML. For now, you can treat it that way.
• Components - React is all about components. You need to think of everything as a component. This will help you maintain the code when working on large scale projects.
• Unidirectional data flow and the Flux architecture - React implements one-way data flow which makes it easy to reason about your app. Flux is a pattern that helps keeping your data unidirectional.
• Virtual DOM - Difference between actual DOM vs virtual DOM

Designing the app

• Observe a good structure for your program. Preferably, divide your src folder into components and services.
• The components folder consists of all your views along with styling. For this assignment, each class usually corresponds to a view. If you want, you can add a styles folder to store all your CSS files.
• The services folder consists of all your API calls. It is suggested that you not make all your API calls in file.
• Take a look at all the components present in the component folder. Observe the class structure along with the JSX.
• To add the router to your application:-

              yarn add react-router-dom

• To run the CRUD app I've made, run the following from inside the react-app directory:-

              yarn start

• Styling your React app with Bootstrap - link

Miscellaneous

• Combining Gin with React. Find a useful tutorial here.
• REST API