On-chain CV contract

Content

• About
• Getting started
• Usage
• Testing
• References

About

This is a smart contract to store and update personal CV information on the Ethereum Blockchain. It has only one interactive feature - user can set likes on published cases.

Actually it is just a simple way to show to potential employer my performance level, but you can use the idea for any purposes. And now you are reading an example of how I can write README.md files.

You can see the realisation of this project here. Also check front-end app repository here.

Getting started

Start with cloning the repository by running git clone and installing all the dependencies:

npm install

Add .env file. You can see example in ./.env.example. Be informed, that crating .env file is obligatorily. Variables required:

• PROVIDER_URL - is a provider URL to deploy the contract. For example Infura
• PRIVATE_KEY - is your blockchain wallet private key. If you use metamask, that is how you can export it
• ETHERSCAN_API_KEY - Etherscan API key to automatically validate deployed contract. If you do not want to deploy contract on external blockchain, or you want to validate it manualy just leave the variable blank "" and change the scripts/deploy.ts file.

Finally run following command to check, that project is installed correctly:

npx hardhat test

Usage

Contract has several simple methods that you can use to get, add, update and delete data. Basically smart-contract is playing role of a back-end app that communicates with blockchain where all CV information is stored.

Main info

Model

Truncated example of data stored in my current CV. If you want to use this contract with provided front-end app, data model should be the same. Otherwise, you can store here any string data.

{
  "name": "Andrey Solovov",
  "position": "Blockchain Developer",
  "hello": "Hello there! Welcome to my crazy web3 CV...",
  "helloPDF": "Hello there! Welcome to my offline CV...",
  "location": "Tbilisi, Georgia",
  "background": "Since 2017, I have worked as...",
  "education": [
    { "year": 2013, "description": "Griboedov Institute ..." }
  ],
  "contacts": {
    "email": { "value": "[email protected]", "link": "" },
    "tg": { "value": "@sigurdrus", "link": "https://t.me/sigurdrus" },
    "linkedIn": { "value": "andrey-solovov", "link": "https://www.linkedin.com/in/andrey-solovov-bb665884" },
    "github": { "value": "/asolovov", "link": "https://github.com/asolovov" }
  },
  "skills": [
    { "name": "Solidity", "description": "Strong knowledge, main cases, QA" }
  ]
}

Update Main Info

• method: updateMainInfo
• type: write
• params: info: string
• requirements: only contract owner

Get Main Info

• method: getMainInfo
• type: read
• returns: string

Cases

Model

Case data has the following structure:

struct Case {
    uint256 id;        // Sets automatically when case added 
    string info;       // JSON string
    uint256 startDate; // Timestamp (I use epoch type). Can not be 0
    uint256 endDate;   // Timestamp (I use epoch type)
    uint256 likes;     // Sets automatically when like is set
}

Truncated example of a case info field stored in my current CV. If you want to use this contract with provided front-end app, data model should be the same. Otherwise, you can store here any string data.

{
  "name": "Project name",
  "link": "https://url",
  "performance": "QA: test cases with...",
  "team": "Uddug",
  "description": "The contract implemented the ERC721 standard...",
  "features": [
    "Public and private sale",
    "Deny-listing addresses",
    "Freezing collection",
    "Editions of ERC721 tokens"
  ]
}

Add case

• method: addCase
• type: write
• params:
  • info: string
  • startDate: uint256
  • endDate: uint256
• requirements:
  • only contract owner
  • startDate cant not be 0

Notes: Start date uses as a validation field to check, if given case ID refers to a deleted or valid case.

Update case

• method: updateCase
• type: write
• params:
  • caseId: uint256
  • info: string
  • startDate: uint256
  • endDate: uint256
• requirements:
  • only contract owner
  • startDate cant not be 0
  • caseId should be valid

Remove case

• method: removeCase

• type: write

• params:

  • caseId: uint256

• requirements:

  • only contract owner
  • caseId should be valid

• getTotalCases

Notes: This method decreases totalLikes variable

Get case

• method: getCase
• type: read
• params:
  • caseId: uint256
• requirements:
  • caseId should be valid
• returns: Case data struct

Get cases

• method: getCases
• type: read
• returns: Case data struct array []

Get total cases

• method: getTotalCases
• type: read
• returns: uint256 total number of not deleted cases

Likes

Set like

• method: setLike
• type: write
• params:
  • caseId: uint256
• requirements:
  • caseId should be valid
  • one user (address) can set only one like on each case

Notes: This method increases totalLikes variable and increases likes field in Case data struct

Get total likes

• method: getTotalLikes
• type: read
• returns: uint256 total likes number

Testing

This project includes a suite of unit tests that can be used to verify the functionality of the contract. Remember to do all the tasks described in Getting started

npx hardhat test

References

This project makes use of the following external resources:

• The OpenZeppelin library for smart contract development and contract upgrades.
• The hardhat development environment for testing and deployment.
• The ethers.js library for interacting with the Ethereum network.