udacity Image Processing

overview

This is a simple API that can be used in two different ways. The first, as a simple placeholder API that allows us to place images into our frontend with the size set via url parameters. second as a library to serve properly scaled versions of our images to the frontend to reduce page load size.

Getting started

to get this project up and running one will need to:

1. install needed dependencies
2. build and execute the application

installation

to install the dependencies download/clone the source code then step into root folder and run the below command

npm install

build phase

to build the application run the below command, it will transpile the typescript code to normal javascript code inside the build folder

npm run build

Start Application

to start the application run the below command , it will start the server on port 3000 and the front-end will be accessible at http://localhost:3000

npm start

Application Home Page http://localhost:3000

APIs

API	METHOD	Description
http://localhost:3000		main page for the front-end application
http://localhost:3000/api/images?filename=image.png&width=100&height=200	GET	resize endpoint need 3 params filename,width and height and makes sure that image exists in full folder or it will throw exception 400
http://localhost:3000/api/images/full	GET	retrieve list of images with full size from full folder
http://localhost:3000/api/images/thumbnails	GET	retrieve list of resized images with from thumb folder
http://localhost:3000/api/images/upload	POST	to upload images to full folder which can use it later for resizing endpoint send multipart/form-data with files as key and value your uploaded image

Testing and Linting

below is some scripts I used it while developing this application to make the code readable and clean also to force me follow best practice

Script	Description
npm run prettier	ensures that all outputted code conforms to a consistent style.
npm run lint	ESLint statically analyzes your code to quickly find problems and help you to fix it
npm run jasmine	to run the unit test for the code but this work on the ./build folder means make sure that you build the application first
npm run test	this to make build then run the jasmine internally to unit test the application