NodeJS MicroService

Features

The API features the following functionalities -

Public Endpoints

Login

• Request body contains an arbitrary username/password pair
• Result: Returns a signed Json Web Token (JWT) which is used to validate future requests.

NOTE: This is a mock-up and accepts all username/password pair.

Protected Endpoints

The following two endpoints are protected. The JWT obtained in the “Login” endpoint must be attached to each request. If the JWT is missing or invalid, these endpoints rejects the request.

Apply Json Patch

• Request body contains a JSON object and a Json Patch object.
• Result: Applies the json patch to the json object, and returns the resulting json object.

Create Thumbnail

• Request contain a public image URL.
• Result: Downloads the image, resize to 50x50 pixels, and return the resulting thumbnail.

Documentation

Setup using NPM

Prerequisites

• NodeJS
• Git

# Get the latest code from github
git clone https://github.com/balrampariyarath/nodejs-microservice.git

# Go to the project directory
cd nodejs-microservice/

# Install NPM dependencies
npm install

# Start the application
npm start

API available at: http://localhost:3000/api/v1/

Build and Run using Docker

Prerequisites

• Docker
• Git

# Get the latest code from github
git clone https://github.com/balrampariyarath/nodejs-microservice.git

# Go to the project directory
cd nodejs-microservice/

# Build the docker image
docker build -t <your username>/nodejs-microservice .

# Run the image
docker run -p 49160:3000 -d <your username>/nodejs-microservice

# Docker mapped the 3000 port inside of the container to the port 49160 on your machine

# Get container ID
docker ps

# To see log / app outputs
docker logs <container id>

API available at: http://localhost:49160/api/v1/

API v1 Methods

Sl.No	Method Name	Method Type	Parameters	URL
1	login	POST	username (String) and password (Password)	http://localhost:3000/api/v1/login
2	validate	POST	token (JWT token)	http://localhost:3000/api/v1/validate
3	applyPatch	POST (Content-Type: application/json)	json (json Object), patch (Json Patch Object) and token (JWT token)	http://localhost:3000/api/v1/applyPatch
4	getThumbnail	POST	image (Image URL) and token (JWT token)	http://localhost:3000/api/v1/getThumbnail

Examples

login API

• POST Request: http://localhost:3000/api/v1/login
• Content-Type: application/x-www-form-urlencoded
• Params:
  username: tester@123
  password: testpass
• Output Format: JSON

{
	"success": "true",
	"token": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6InRlc3RlckAxMjMiLCJwYXNzd29yZCI6InRlc3RwYXNzIiwiaWF0IjoxNTA2MDE5MjUyfQ.HSMPTV_da14hFqsjMP2aLATmseV76wc0x9YrKEP7_KE"
}

validate API

• POST Request: http://localhost:3000/api/v1/validate
• Content-Type: application/x-www-form-urlencoded
• Params:
  token: XXX-XXX-XXXXXXXXXXX // token
• Output Format: Boolean (true/false)

# If token is valid
true
# Invalid Token
False

applyPatch API

• POST Request: http://localhost:3000/api/v1/applyPatch
• Content-Type: application/json
• Params:

{
	"token":"eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJ1c2VybmFtZSI6ImJhbHJhbSIsInBhc3N3b3JkIjoicGFzc3dvcmQiLCJpYXQiOjE1MDU5ODY3Njd9.rSG-BQMLZc8-G3X4hgmlCD6wFA71Tc9CX9TGpS-nuxw",
	"patch":[
		{ "op": "replace", "path": "/baz", "value": "boo" },
		{ "op": "add", "path": "/hello", "value": ["world"] },
		{ "op": "remove", "path": "/foo"}
	],
	"json":{
		"baz": "qux",
		"foo": "bar"
	}
}

• Output Format: JSON

{
	"success": "true",
	"output": {
		"baz": "boo",
		"hello": ["world"]
	}
}

getThumbnail API

• POST Request: http://localhost:3000/api/v1/getThumbnail
• Content-Type: application/x-www-form-urlencoded
• Params:
  image: https://cdn.pixabay.com/photo/2013/04/06/11/50/image-editing-101040_960_720.jpg
  token: XXX-XXX-XXXXXXXXXXX // a valid token
• Output Format: JSON

{
	"success": "true",
	"filename": "assets/thumbnails/image-editing-101040_960_720.jpg"
}

Original Image Uploaded

Image Source: Google

Thumbnail Generated

Logs and Assets

• Logs are maintained in logs directory
• All thumbnails are generated into assets/thumbnails ditectory

Libraries Used

• Body Parser

• Express

• JsonWebToken

• Image-Downloader

• Json Patch

• GraphicsMagick

• Winston (Logging)

To Do

• Unit Tests
• Adding a JS Linter