In this project, I built a RESTful API using Express.js that interface with my private blockchain. This project is consist of two end points for use this api.

• GET Block
• POST Block

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes.

To install the software, you need to doownload the following:

1. Install Node.js on your computer.
2. Clone or download the repository to your local computer.
3. Open the terminal and install the packages: npm install.
4. Initialize node.js project where files are located.

npm init

This project has the following dependencies:

  "dependencies": {
    "body-parser": "^1.19.0",
    "crypto-js": "^3.1.9-1",
    "express": "^4.16.4",
    "level": "^5.0.1"
  }

You can install and save dependencies:

npm install crypto-js --save
npm install level --save
npm install body-parser --save
npm install express --save

Run your application node app.js.

node app.js

• The REST API provides us two endpoints to interact with our private Blockchain The API is runs on localhost, with port 8000.

• URL : /block/{BLOCK_HEIGHT}

• Method : GET

• URL Path Params : BLOCK_HEIGHT (Retrive Block Height)

curl --request GET -i http://localhost:8000/block/0  # will return Block #0 from blockchain

• URL : /block
• Method : GET
• Request Body : {"data" : "some data example"}

curl -X POST \
  http://localhost:8000/block \
  -H 'Cache-Control: no-cache' \
  -H 'Content-Type: application/json' \
  -H 'Postman-Token: 1e551722-4382-49cc-84f1-19d3d433c1e7' \
  -d '{
    "data":"Some data example"
}'

• Node.js - The JavaScript runtime used
• Express.js - The web API framework used
• LevelDB - Used to persist blockchain data on disk

• Mingu Kang - Github