Ethers Simple Storage

This is part of the FreeCodeCamp Solidity & Javascript Blockchain Course.

Video Link : ⌨️ (05:30:42) Lesson 5: Ethers.js Simple Storage

Getting Started

Requirements

git
- You'll know you did it right if you can run git --version and you see a response like git version x.x.x
Nodejs
- You'll know you've installed nodejs right if you can run:
  - node --version and get an ouput like: vx.x.x
Yarn instead of npm
- You'll know you've installed yarn right if you can run:
  - yarn --version and get an output like: x.x.x
  - You might need to install it with npm
ganache
- You'll know you did it right if you can run the application and see:
- You can alternatively use ganache-cli or hardhat

Optional Gitpod

If you can't or don't want to run and install locally, you can work with this repo in Gitpod. If you do this, you can skip the clone this repo part.

Setup

Clone this repo

git clone https://github.com/PatrickAlphaC/ethers-simple-storage
cd ethers-simple-storage

Then install dependencies

yarn

Note: You'll notice in our package.json we are using "solc": "0.8.7-fixed". Usually, you'll just be able to do "solc": "0.8.7" to get a specific version, but there was a bit of an issue with that one... You'll find out why we use 0.8.7

Typescript

If you like typescript, run git checkout typescript then run yarn

Usage

Run your ganache local chain, by hitting quickstart on your ganache application

Save the workspace. This way, next time you open ganache you can start the workspace you've created, otherwise you'll have to redo all the steps below.

Copy the RPC SERVER sting in your ganache CLI, and place it into your .env file similar to what's in .env.example.

.env Example:

RPC_URL=http://0.0.0.0:8545

Hit the key on one of the accounts, and copy the key you see and place it into your .env file, similar to what you see in .env.example.

.env Example:

PRIVATE_KEY=11ee3108a03081fe260ecdc106554d09d9d1209bcafd46942b10e02943effc4a

Compile your code

Run

yarn compile

You'll see files SimpleStorage_sol_SimpleStorage.abi and SimpleStorage_sol_SimpleStorage.bin be created.

Run your application

node deploy.js

For WSL users

yarn add ganache

Change Server settings in Ganache

Settings > Server > Host Name

Change Host Name to vEthernet (WSL)

Run your application

node deploy.js

Deploying to a testnet

Make sure you have a metamask or other wallet, and export the private key.

IMPORTANT

USE A METAMASK THAT DOESNT HAVE ANY REAL FUNDS IN IT. Just in case you accidentally push your private key to a public place. I highly recommend you use a different metamask or wallet when developing.

Export your private key and place it in your .env file, as done above.
Go to Alchemy and create a new project on the testnet of choice (ie, Sepolia)
Grab your URL associated with the testnet, and place it into your .env file.
Make sure you have testnet ETH in your account. You can get some here. You should get testnet ETH for the same testnet that you made a project in Alchemy (ie, Sepolia)
Run

node deploy.js

Troubleshooting: Ethers 6.X.X instability

const provider = new ethers.providers.JsonRpcProvider(process.env.RPC_URL)
                                      ^

TypeError: Cannot read properties of undefined (reading 'JsonRpcProvider')

If you are experiencing issues with the latest version of Ethers, ethers ^6.0.2, try

const provider = new ethers.JsonRpcProvider(process.env.RPC_URL)

as providers were migrated to ethers.* in version 6 (previously ethers.providers.*). reference: https://docs.ethers.org/v6/migrating/#migrate-providers

Or you can easily solve the problem by downgrading to a previous version of Ethers, such as ethers 5.7.2.

To downgrade to ethers 5.7.2, run either of the following commands on your command line interface, depending on your package manager:

For npm: