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harmony-cosmos-bridge-demo

This is a demonstration of token transfer using IBC between a Harmony network and a Cosmos-based blockchain.

IBC Light Client

We use yui-ibc-solidity for IBC core and our customed tendermint-sol as a Tendermint light client on Harmony
We use ibc-harmony-client as a Harmony light client on Cosmos-based blockchain

Directory structure

contracts ... contracts and migration scripts for harmony
relayer ... IBC relayer using yui-relayer
- chains/harmony ... harmony modules
- chains/tendermint ... tendermint modules for tendermint-sol
tests ... test environments
- cases ... E2E test case
- chains/harmony ... configs for harmony localnet
- chains/tendermint ... configs for tendermint localnet

Setup

Prerequisites

bash 4.0 or higher
golang 1.16 or higher
node.js 16

Env

Example:

# assume that RPC port offset is 500
export HARMONY_LOCAL_SHARD_0_URL=http://localhost:9598
export HARMONY_LOCAL_SHARD_1_URL=http://localhost:9596

export HARMONY_GAS_LIMIT=100000000
export HARMONY_GAS_PRICE=1000000000

# used for deploying contracts
# cf. https://github.com/harmony-one/harmony/pull/3332
export HARMONY_LOCAL_PRIVATE_KEY: '0x1f84c95ac16e6a50f08d44c7bde7aff8742212fda6e4321fde48bf83bef266dc'

Harmony localnet url is configured based on tests/chains/harmony/configs/localnet_deploy.config.

Building Relayer

Relayer needs libraries for harmony. At first, we need to build the libraries.

make clone-harmony
make build-harmony

Then, we will get a relayer with the following command.

make build-relayer

Preparing Harmony Local Network

The following commands creates a Harmony localnet docker image with deployed contracts.

cd tests/chains/harmony
make docker-image

Preparing Cosmos Local Network

The following command creates a Cosmos local network image.

cd tests/chains/tendermint
make docker-image

E2E

The following commands brings up the two networks, performs an IBC Handshake, and transfers token.

cd tests/cases/tm2harmony
make network
make test
make network-down