pezkuwi-subxt/cumulus/parachains/runtimes/bridge-hubs

• Bridge-hub Parachains
  • Requirements for local run/testing
  • How to test local Rococo <-> Westend bridge
    • Run Rococo/Westend chains with zombienet
    • Init bridge and run relayer between BridgeHubRococo and BridgeHubWestend
    • Initialize configuration for transfer asset over bridge (ROCs/WNDs)
    • Send messages - transfer asset over bridge (ROCs/WNDs)
    • Claim relayer's rewards on BridgeHubRococo and BridgeHubWestend
  • How to test local BridgeHubKusama/BridgeHubPolkadot

Bridge-hub Parachains

BridgeHub(s) are system parachains that will house trustless bridges from the local ecosystem to others. The current trustless bridges planned for the BridgeHub(s) are:

• BridgeHubPolkadot system parachain:
  1. Polkadot <-> Kusama bridge
  2. Polkadot <-> Ethereum bridge (Snowbridge)
• BridgeHubKusama system parachain:
  1. Kusama <-> Polkadot bridge
  2. Kusama <-> Ethereum bridge The high-level responsibilities of each bridge living on BridgeHub:
• sync finality proofs between relay chains (or equivalent)
• sync finality proofs between BridgeHub parachains
• pass (XCM) messages between different BridgeHub parachains

Requirements for local run/testing

# Prepare empty directory for testing
mkdir -p ~/local_bridge_testing/bin
mkdir -p ~/local_bridge_testing/logs

---
# 1. Install zombienet
Go to: https://github.com/paritytech/zombienet/releases
Copy the apropriate binary (zombienet-linux) from the latest release to ~/local_bridge_testing/bin


---
# 2. Build polkadot binary

We need polkadot binary with "fast-runtime" feature:

cd <polkadot-sdk-git-repo-dir>
cargo build --release --features fast-runtime --bin polkadot
cp target/release/polkadot ~/local_bridge_testing/bin/polkadot

cargo build --release --features fast-runtime --bin polkadot-prepare-worker
cp target/release/polkadot-prepare-worker ~/local_bridge_testing/bin/polkadot-prepare-worker

cargo build --release --features fast-runtime --bin polkadot-execute-worker
cp target/release/polkadot-execute-worker ~/local_bridge_testing/bin/polkadot-execute-worker


---
# 3. Build substrate-relay binary
git clone https://github.com/paritytech/parity-bridges-common.git
cd parity-bridges-common

# checkout desired branch or use master:
# git checkout -b master --track origin/master
# `polkadot-staging` (recommended) is stabilized and compatible for Cumulus releases
# `master` is latest development
git checkout -b polkadot-staging --track origin/polkadot-staging

cargo build --release -p substrate-relay
cp target/release/substrate-relay ~/local_bridge_testing/bin/substrate-relay


---
# 4. Build cumulus polkadot-parachain binary
cd <polkadot-sdk-git-repo-dir>

cargo build --release -p polkadot-parachain-bin
cp target/release/polkadot-parachain ~/local_bridge_testing/bin/polkadot-parachain
cp target/release/polkadot-parachain ~/local_bridge_testing/bin/polkadot-parachain-asset-hub

How to test local Rococo <-> Westend bridge

Run Rococo/Westend chains with zombienet

cd <polkadot-sdk-git-repo-dir>

# Rococo + BridgeHubRococo + AssetHub for Rococo (mirroring Kusama)
POLKADOT_BINARY_PATH=~/local_bridge_testing/bin/polkadot \
POLKADOT_PARACHAIN_BINARY_PATH=~/local_bridge_testing/bin/polkadot-parachain \
POLKADOT_PARACHAIN_BINARY_PATH_FOR_ASSET_HUB_ROCOCO=~/local_bridge_testing/bin/polkadot-parachain-asset-hub \
	~/local_bridge_testing/bin/zombienet-linux --provider native spawn ./cumulus/zombienet/bridge-hubs/bridge_hub_rococo_local_network.toml

cd <polkadot-sdk-git-repo-dir>

# Westend + BridgeHubWestend + AssetHub for Westend (mirroring Polkadot)
POLKADOT_BINARY_PATH=~/local_bridge_testing/bin/polkadot \
POLKADOT_PARACHAIN_BINARY_PATH=~/local_bridge_testing/bin/polkadot-parachain \
POLKADOT_PARACHAIN_BINARY_PATH_FOR_ASSET_HUB_WESTEND=~/local_bridge_testing/bin/polkadot-parachain-asset-hub \
	~/local_bridge_testing/bin/zombienet-linux --provider native spawn ./cumulus/zombienet/bridge-hubs/bridge_hub_westend_local_network.toml

Init bridge and run relayer between BridgeHubRococo and BridgeHubWestend

Accounts of BridgeHub parachains:

• Bob is pallet owner of all bridge pallets

Run with script

cd <polkadot-sdk-git-repo-dir>

./cumulus/scripts/bridges_rococo_westend.sh run-relay

Check relay-chain headers relaying:

• Rococo parachain: - https://polkadot.js.org/apps/?rpc=ws%3A%2F%2F127.0.0.1%3A8943#/chainstate - Pallet: bridgeWestendGrandpa - Keys: bestFinalized()
• Westend parachain: - https://polkadot.js.org/apps/?rpc=ws%3A%2F%2F127.0.0.1%3A8945#/chainstate - Pallet: bridgeRococoGrandpa - Keys: bestFinalized()

Check parachain headers relaying:

• Rococo parachain: - https://polkadot.js.org/apps/?rpc=ws%3A%2F%2F127.0.0.1%3A8943#/chainstate - Pallet: bridgeWestendParachains - Keys: parasInfo(None)
• Westend parachain: - https://polkadot.js.org/apps/?rpc=ws%3A%2F%2F127.0.0.1%3A8945#/chainstate - Pallet: bridgeRococoParachains - Keys: parasInfo(None)

Initialize configuration for transfer asset over bridge (ROCs/WNDs)

This initialization does several things:

• creates ForeignAssets for wrappedROCs/wrappedWNDs
• drips SA for AssetHubRococo on AssetHubWestend (and vice versa) which holds reserved assets on source chains

cd <polkadot-sdk-git-repo-dir>

./cumulus/scripts/bridges_rococo_westend.sh init-asset-hub-rococo-local
./cumulus/scripts/bridges_rococo_westend.sh init-bridge-hub-rococo-local
./cumulus/scripts/bridges_rococo_westend.sh init-asset-hub-westend-local
./cumulus/scripts/bridges_rococo_westend.sh init-bridge-hub-westend-local

Send messages - transfer asset over bridge (ROCs/WNDs)

Do reserve-backed transfers:

cd <polkadot-sdk-git-repo-dir>

# ROCs from Rococo's Asset Hub to Westend's.
./cumulus/scripts/bridges_rococo_westend.sh reserve-transfer-assets-from-asset-hub-rococo-local

cd <polkadot-sdk-git-repo-dir>

# WNDs from Westend's Asset Hub to Rococo's.
./cumulus/scripts/bridges_rococo_westend.sh reserve-transfer-assets-from-asset-hub-westend-local

• open explorers: (see zombienets)
  • AssetHubRococo (see events xcmpQueue.XcmpMessageSent, polkadotXcm.Attempted) https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:9910#/explorer
  • BridgeHubRococo (see bridgeWestendMessages.MessageAccepted) https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:8943#/explorer
  • BridgeHubWestend (see bridgeRococoMessages.MessagesReceived, xcmpQueue.XcmpMessageSent) https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:8945#/explorer
  • AssetHubWestend (see foreignAssets.Issued, xcmpQueue.Success) https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:9010#/explorer
  • BridgeHubRocococ (see bridgeWestendMessages.MessagesDelivered) https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:8943#/explorer

Do reserve withdraw transfers: (when previous is finished)

cd <polkadot-sdk-git-repo-dir>

# wrappedWNDs from Rococo's Asset Hub to Westend's.
./cumulus/scripts/bridges_rococo_westend.sh withdraw-reserve-assets-from-asset-hub-rococo-local

cd <polkadot-sdk-git-repo-dir>

# wrappedROCs from Westend's Asset Hub to Rococo's.
./cumulus/scripts/bridges_rococo_westend.sh withdraw-reserve-assets-from-asset-hub-westend-local

Claim relayer's rewards on BridgeHubRococo and BridgeHubWestend

Accounts of BridgeHub parachains:

• //Charlie is relayer account on BridgeHubRococo
• //Charlie is relayer account on BridgeHubWestend

cd <polkadot-sdk-git-repo-dir>

# Claim rewards on BridgeHubWestend:
./cumulus/scripts/bridges_rococo_westend.sh claim-rewards-bridge-hub-rococo-local

# Claim rewards on BridgeHubWestend:
./cumulus/scripts/bridges_rococo_westend.sh claim-rewards-bridge-hub-westend-local

• open explorers: (see zombienets)
  • BridgeHubRococo (see 2x bridgeRelayers.RewardPaid) https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:8943#/explorer
  • BridgeHubWestend (see 2x bridgeRelayers.RewardPaid) https://polkadot.js.org/apps/?rpc=ws://127.0.0.1:8945#/explorer

How to test local BridgeHubKusama/BridgeHubPolkadot

TODO: see # !!! READ HERE above