web3-events-example

A simple example of a smart contract and emits events and 2 clients (on in node.js and the other in go) that will deploy and loop over the events emitted by transactions that we submit.

This is intended as a check that an EVM compatible chain is working with event filters as expected.

install

You will need:

• docker
• node.js (>=16)
• go (>=1.16)

geth

If you want to test against a local geth node, you can run:

./stack geth
./stack geth-fund

This will start a local geth node and print out the environment variables that you need to export for the various clients.

other chains

If you want to connect to other chains you can export the following variables:

• PRIVATE_KEY - the private key of the wallet with funds to submit transactions
• RPC_URL - the url of the RPC endpoint
• CHAIN_ID - the chain id of the chain you are connecting to

node.js

To run the node.js client:

export PRIVATE_KEY=xxx
export RPC_URL=xxx
export CHAIN_ID=xxx
cd js
npm install
node events.js

go

To run the go client:

export PRIVATE_KEY=xxx
export RPC_URL=xxx
export CHAIN_ID=xxx
cd go
go run events.go

re-compile

The artifacts folder contains the ABI and the bytecode of the contract.

The go/contract/contract.go file contains the golang bindings for said contract.

If you want to re-generate these because the smart contract has changed:

./stack compile