Project4-Build-a-Private-Blockchain-Notary-Service

In this project, we build a Star Registry Service that allows users to claim ownership of their favorite star in the night sky. This application is build usijng RESTful API, ExpressJS

Download project

git clone https://github.com/msharekh/Project4-Build-a-Private-Blockchain-Notary-Service.git

Installation

Install project dependencies:

$ npm install

REQUIRED LIBRARIES

• npm: npm install npm@latest -g
• express: npm install express --save
• body-parser: npm install body-parser --save
• crypto-js: npm install crypto-js --save
• level: npm install level --save
• bitcoinjs-lib": npm install bitcoinjs-lib --save
• bitcoinjs-message": npm install bitcoinjs-message --save
• hex2ascii": npm install hex2ascii --save

to start application run this command:

node app.js

Usage

validate request with JSON response:

User makes a request to submit a star and sends address for example, when "address":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc" and use the following url: (http://localhost:8000/requestValidation)

curl -X POST \
                http://localhost:8000/requestValidation \
                -H 'Content-Type: application/json' \
                -H 'cache-control: no-cache' \
                -d '{ "address":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc" }'

the API responds with a message that the user should sign with its private keys:

{  
   "walletAddress":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc",
   "requestTimeStamp":"1544766868",
   "message":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc:1544766868:starRegistry",
   "validationWindow":291,
   "mempoolStatus":"Valid"
}

User signs the message and sends it to the service.

for example, when "signature":"IKQR7cn7bOGcHKM7tjCmLlZfLwDYwWdhNjaI7niyY9KJLmsakZ3l9Egent4+aJt7Nqv6l+9340UWXRHhqqAQ1+U=" and use the following url: (http://localhost:8000/message-signature/validate)

curl -X POST \
            http://localhost:8000/message-signature/validate \
            -H 'Content-Type: application/json' \
            -H 'cache-control: no-cache' \
            -d '{
                "address":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc",
                "signature":"IKQR7cn7bOGcHKM7tjCmLlZfLwDYwWdhNjaI7niyY9KJLmsakZ3l9Egent4+aJt7Nqv6l+9340UWXRHhqqAQ1+U="
            }'

Service checks if signature is valid. it informs the user of the result

{  
   "registerStar":true,
   "status":{  
      "address":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc",
      "requestTimeStamp":"1544766868",
      "message":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc:1544766868:starRegistry",
      "validationWindow":291,
      "messageSignature":true
   }
}

If signature is valid, user is able to submit a star.

for example, when

"star": {
                        "dec": "69° 27'\'' 1.2",
                        "ra": "9h 54m 26s",
                        "story": "Found star using https://www.google.com/sky/"
                    }

and use the following url: (http://localhost:8000/block)

curl -X POST \
                http://localhost:8000/block \
                -H 'Content-Type: application/json' \
                -H 'cache-control: no-cache' \
                -d '{
                "address": "1Kc8NccSW4qieURf2AjikTzs99vq1oBerc",
                "star": {
                        "dec": "69° 27'\'' 1.2",
                        "ra": "9h 54m 26s",
                        "story": "Found star using https://www.google.com/sky/"
                    }
            	    }'

After submitting a star, the same user has to restart all the process to be able to submit another star.

{  
   "hash":"8a7776a2e7e0973c3d8a5b2e4ea7b143243fa2f5e2b1e5a15129dfa0d7b789e1",
   "height":8,
   "body":{  
      "address":"1Kc8NccSW4qieURf2AjikTzs99vq1oBerc",
      "star":{  
         "dec":"69° 27' 1.2",
         "ra":"9h 54m 26s",
         "story":"466f756e642073746172207573696e672068747470733a2f2f7777772e676f6f676c652e636f6d2f736b792f",
         "storyDecoded":"Found star using https://www.google.com/sky/"
      }
   },
   "time":"1544809720",
   "previousBlockHash":"6bf6374522a1721b150126bc2b7f0a015cdb8ad068cf9cc1c38ab5bb605271da"
}

Star Lookup

Get Star block by hash with JSON response. Use the URL (http://localhost:8000/stars/hash:[HASH])

Get Star block by wallet address (blockchain identity) with JSON response. Use the URL (http://localhost:8000/stars/address:[ADDRESS])

Get star block by star block height with JSON response. Use the URL (http://localhost:8000/block/[HEIGHT])