pezkuwi-subxt/parachains/runtimes/bridge-hubs

Bride-hubs Parachain

Implementation of BridgeHub, a blockchain to support message passing between Substrate based chains like Polkadot and Kusama networks.

BridgeHub allows users to:

• Passing arbitrary messages between different Substrate chains (Polkadot <-> Kusama). -- Message passing is

Every BridgeHub is meant to be common good parachain with main responsibilities:

• sync finality proofs between relay chains
• sync finality proofs between BridgeHub parachains
• pass (XCM) messages between different BridgeHub parachains

How to test locally Rococo <-> Wococo

Prepare/Build/Deploy

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


# 1. Build polkadot binary
git clone https://github.com/paritytech/polkadot.git
cd polkadot
cargo build --release
cp target/release/polkadot ~/local_bridge_testing/bin/polkadot

# 2. Build cumulus polkadot-parachain binary
cd <cumulus-git-repo-dir>
cargo build --release --locked -p polkadot-parachain@0.9.230
cp target/release/polkadot-parachain ~/local_bridge_testing/bin/polkadot-parachain

# 3. Build substrate-relay binary
git clone https://github.com/paritytech/parity-bridges-common.git
cd parity-bridges-common
cargo build -p substrate-relay
cp target/release/substrate-relay ~/local_bridge_testing/bin/substrate-relay

Run chains (Rococo + BridgeHub, Wococo + BridgeHub) from ./scripts/bridges_rococo_wococo.sh

./scripts/bridges_rococo_wococo.sh stop
./scripts/bridges_rococo_wococo.sh start-rococo
./scripts/bridges_rococo_wococo.sh start-wococo

Run relayers (Rococo, Wococo)

Accounts of BridgeHub parachains:

• Bob is pallet owner of all bridge pallets
• Alice is Sudo

1. Init bridges

# Rococo -> Wococo
RUST_LOG=runtime=trace,rpc=trace,runtime::bridge=trace \
	~/local_bridge_testing/bin/substrate-relay init-bridge rococo-to-bridge-hub-wococo \
	--source-host localhost \
	--source-port 48943 \
	--target-host localhost \
	--target-port 8945 \
	--target-signer //Bob

# Wococo -> Rococo
RUST_LOG=runtime=trace,rpc=trace,runtime::bridge=trace \
	~/local_bridge_testing/bin/substrate-relay init-bridge wococo-to-bridge-hub-rococo \
	--source-host localhost \
	--source-port 48945 \
	--target-host localhost \
	--target-port 8943 \
	--target-signer //Bob

2. Relay (Grandpa relay-chain) headers

source-host/source-port - WS-port of collator's inner RelayChain validator target-host/target-port - WS-port of BridgeHub collator

# Rococo -> Wococo
RUST_LOG=runtime=trace,rpc=trace,runtime::bridge=trace \
	~/local_bridge_testing/bin/substrate-relay relay-headers rococo-to-bridge-hub-wococo \
	--source-host localhost \
	--source-port 48943 \
	--target-host localhost \
	--target-port 8945 \
	--target-signer //Bob \
	--target-transactions-mortality=4

# Wococo -> Rococo
RUST_LOG=runtime=trace,rpc=trace,runtime::bridge=trace \
	~/local_bridge_testing/bin/substrate-relay relay-headers wococo-to-bridge-hub-rococo \
	--source-host localhost \
	--source-port 48945 \
	--target-host localhost \
	--target-port 8943 \
	--target-signer //Bob \
	--target-transactions-mortality=4

Check parachain collators:

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

3. Relay (BridgeHub parachain) headers

TODO:

4. Relay (XCM) messages

TODO:

---

Git subtree ./bridges

Add Bridges repo as a local remote and synchronize it with latest master from bridges repo:

git remote add -f bridges git@github.com:paritytech/parity-bridges-common.git
# (ran just only first time, when subtree was initialized)
# git subtree add --prefix=bridges bridges master --squash

# Synchro bridges repo
git fetch bridges --prune
git subtree pull --prefix=bridges bridges master --squash

We use --squash to avoid adding individual commits and rather squashing them all into one.

Now we use master branch, but in future, it could change to some release branch/tag.

Original ./bridges/Cargo.toml was renamed to ./bridges/Cargo.toml_removed_for_bridges_subtree_feature to avoid confusion for Cargo having multiple workspaces.

---

TODO: fix zombienet ports as bridges_rococo_wococo.sh, because networks colide and interfere by default, because of autodiscovery on localhost

Run chains (Rococo + BridgeHub, Wococo + BridgeHub) with Zombienet

# Rococo
POLKADOT_BINARY_PATH=~/local_bridge_testing/bin/polkadot \
	POLKADOT_PARACHAIN_BINARY_PATH=~/local_bridge_testing/bin/polkadot-parachain \
	~/local_bridge_testing/bin/zombienet-linux --provider native spawn ./zombienet_tests/0004-run_bridge_hubs_rococo.toml

# Wococo
POLKADOT_BINARY_PATH=~/local_bridge_testing/bin/polkadot \
	POLKADOT_PARACHAIN_BINARY_PATH=~/local_bridge_testing/bin/polkadot-parachain \
	~/local_bridge_testing/bin/zombienet-linux --provider native spawn ./zombienet_tests/0004-run_bridge_hubs_wococo.toml