SourceClient for SubstrateMessagesSource
where
C: Chain,
C::Header: DeserializeOwned,
C::Index: DeserializeOwned,
C::BlockNumber: BlockNumberBase,
P: SubstrateMessageLane<
MessagesProof = SubstrateMessagesProof,
SourceHeaderNumber = ::Number,
SourceHeaderHash = ::Hash,
SourceChain = C,
>,
P::TargetChain: Chain,
P::TargetHeaderNumber: Decode,
P::TargetHeaderHash: Decode,
R: Send + Sync + MessagesConfig,
I: Send + Sync + Instance,
{
async fn state(&self) -> Result, SubstrateError> {
// we can't continue to deliver confirmations if source node is out of sync, because
// it may have already received confirmations that we're going to deliver
self.client.ensure_synced().await?;
read_client_state::<_, P::TargetHeaderHash, P::TargetHeaderNumber>(
&self.client,
P::BEST_FINALIZED_TARGET_HEADER_ID_AT_SOURCE,
)
.await
}
async fn latest_generated_nonce(
&self,
id: SourceHeaderIdOf,
) -> Result<(SourceHeaderIdOf
, MessageNonce), SubstrateError> {
let encoded_response = self
.client
.state_call(
P::OUTBOUND_LANE_LATEST_GENERATED_NONCE_METHOD.into(),
Bytes(self.lane_id.encode()),
Some(id.1),
)
.await?;
let latest_generated_nonce: MessageNonce =
Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
Ok((id, latest_generated_nonce))
}
async fn latest_confirmed_received_nonce(
&self,
id: SourceHeaderIdOf
,
) -> Result<(SourceHeaderIdOf
, MessageNonce), SubstrateError> {
let encoded_response = self
.client
.state_call(
P::OUTBOUND_LANE_LATEST_RECEIVED_NONCE_METHOD.into(),
Bytes(self.lane_id.encode()),
Some(id.1),
)
.await?;
let latest_received_nonce: MessageNonce =
Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
Ok((id, latest_received_nonce))
}
async fn generated_messages_weights(
&self,
id: SourceHeaderIdOf
,
nonces: RangeInclusive,
) -> Result {
let encoded_response = self
.client
.state_call(
P::OUTBOUND_LANE_MESSAGES_DISPATCH_WEIGHT_METHOD.into(),
Bytes((self.lane_id, nonces.start(), nonces.end()).encode()),
Some(id.1),
)
.await?;
make_message_weights_map::(
Decode::decode(&mut &encoded_response.0[..]).map_err(SubstrateError::ResponseParseFailed)?,
nonces,
)
}
async fn prove_messages(
&self,
id: SourceHeaderIdOf,
nonces: RangeInclusive,
proof_parameters: MessageProofParameters,
) -> Result<(SourceHeaderIdOf, RangeInclusive, P::MessagesProof), SubstrateError> {
let mut storage_keys = Vec::with_capacity(nonces.end().saturating_sub(*nonces.start()) as usize + 1);
let mut message_nonce = *nonces.start();
while message_nonce <= *nonces.end() {
let message_key = pallet_bridge_messages::storage_keys::message_key::(&self.lane_id, message_nonce);
storage_keys.push(message_key);
message_nonce += 1;
}
if proof_parameters.outbound_state_proof_required {
storage_keys.push(pallet_bridge_messages::storage_keys::outbound_lane_data_key::(
&self.lane_id,
));
}
let proof = self
.client
.prove_storage(storage_keys, id.1)
.await?
.iter_nodes()
.collect();
let proof = FromBridgedChainMessagesProof {
bridged_header_hash: id.1,
storage_proof: proof,
lane: self.lane_id,
nonces_start: *nonces.start(),
nonces_end: *nonces.end(),
};
Ok((id, nonces, (proof_parameters.dispatch_weight, proof)))
}
async fn submit_messages_receiving_proof(
&self,
generated_at_block: TargetHeaderIdOf,
proof: P::MessagesReceivingProof,
) -> Result<(), SubstrateError> {
self.client
.submit_signed_extrinsic(self.lane.source_transactions_author(), move |transaction_nonce| {
self.lane
.make_messages_receiving_proof_transaction(transaction_nonce, generated_at_block, proof)
})
.await?;
Ok(())
}
async fn require_target_header_on_source(&self, id: TargetHeaderIdOf
) {
if let Some(ref target_to_source_headers_relay) = self.target_to_source_headers_relay {
target_to_source_headers_relay.require_finalized_header(id).await;
}
}
}
pub async fn read_client_state(
self_client: &Client,
best_finalized_header_id_method_name: &str,
) -> Result, HeaderId>, SubstrateError>
where
SelfChain: Chain,
SelfChain::Header: DeserializeOwned,
SelfChain::Index: DeserializeOwned,
BridgedHeaderHash: Decode,
BridgedHeaderNumber: Decode,
{
// let's read our state first: we need best finalized header hash on **this** chain
let self_best_finalized_header_hash = self_client.best_finalized_header_hash().await?;
let self_best_finalized_header = self_client.header_by_hash(self_best_finalized_header_hash).await?;
let self_best_finalized_id = HeaderId(*self_best_finalized_header.number(), self_best_finalized_header_hash);
// now let's read our best header on **this** chain
let self_best_header = self_client.best_header().await?;
let self_best_hash = self_best_header.hash();
let self_best_id = HeaderId(*self_best_header.number(), self_best_hash);
// now let's read id of best finalized peer header at our best finalized block
let encoded_best_finalized_peer_on_self = self_client
.state_call(
best_finalized_header_id_method_name.into(),
Bytes(Vec::new()),
Some(self_best_hash),
)
.await?;
let decoded_best_finalized_peer_on_self: (BridgedHeaderNumber, BridgedHeaderHash) =
Decode::decode(&mut &encoded_best_finalized_peer_on_self.0[..]).map_err(SubstrateError::ResponseParseFailed)?;
let peer_on_self_best_finalized_id = HeaderId(
decoded_best_finalized_peer_on_self.0,
decoded_best_finalized_peer_on_self.1,
);
Ok(ClientState {
best_self: self_best_id,
best_finalized_self: self_best_finalized_id,
best_finalized_peer_at_best_self: peer_on_self_best_finalized_id,
})
}
fn make_message_weights_map(
weights: Vec<(MessageNonce, Weight, u32)>,
nonces: RangeInclusive,
) -> Result {
let make_missing_nonce_error = |expected_nonce| {
Err(SubstrateError::Custom(format!(
"Missing nonce {} in messages_dispatch_weight call result. Expected all nonces from {:?}",
expected_nonce, nonces,
)))
};
let mut weights_map = MessageWeightsMap::new();
// this is actually prevented by external logic
if nonces.is_empty() {
return Ok(weights_map);
}
// check if last nonce is missing - loop below is not checking this
let last_nonce_is_missing = weights
.last()
.map(|(last_nonce, _, _)| last_nonce != nonces.end())
.unwrap_or(true);
if last_nonce_is_missing {
return make_missing_nonce_error(*nonces.end());
}
let mut expected_nonce = *nonces.start();
let mut is_at_head = true;
for (nonce, weight, size) in weights {
match (nonce == expected_nonce, is_at_head) {
(true, _) => (),
(false, true) => {
// this may happen if some messages were already pruned from the source node
//
// this is not critical error and will be auto-resolved by messages lane (and target node)
log::info!(
target: "bridge",
"Some messages are missing from the {} node: {:?}. Target node may be out of sync?",
C::NAME,
expected_nonce..nonce,
);
}
(false, false) => {
// some nonces are missing from the middle/tail of the range
//
// this is critical error, because we can't miss any nonces
return make_missing_nonce_error(expected_nonce);
}
}
weights_map.insert(
nonce,
MessageWeights {
weight,
size: size as _,
},
);
expected_nonce = nonce + 1;
is_at_head = false;
}
Ok(weights_map)
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn make_message_weights_map_succeeds_if_no_messages_are_missing() {
assert_eq!(
make_message_weights_map::(vec![(1, 0, 0), (2, 0, 0), (3, 0, 0)], 1..=3,)
.unwrap(),
vec![
(1, MessageWeights { weight: 0, size: 0 }),
(2, MessageWeights { weight: 0, size: 0 }),
(3, MessageWeights { weight: 0, size: 0 }),
]
.into_iter()
.collect(),
);
}
#[test]
fn make_message_weights_map_succeeds_if_head_messages_are_missing() {
assert_eq!(
make_message_weights_map::(vec![(2, 0, 0), (3, 0, 0)], 1..=3,).unwrap(),
vec![
(2, MessageWeights { weight: 0, size: 0 }),
(3, MessageWeights { weight: 0, size: 0 }),
]
.into_iter()
.collect(),
);
}
#[test]
fn make_message_weights_map_fails_if_mid_messages_are_missing() {
assert!(matches!(
make_message_weights_map::(vec![(1, 0, 0), (3, 0, 0)], 1..=3,),
Err(SubstrateError::Custom(_))
));
}
#[test]
fn make_message_weights_map_fails_if_tail_messages_are_missing() {
assert!(matches!(
make_message_weights_map::(vec![(1, 0, 0), (2, 0, 0)], 1..=3,),
Err(SubstrateError::Custom(_))
));
}
#[test]
fn make_message_weights_map_fails_if_all_messages_are_missing() {
assert!(matches!(
make_message_weights_map::(vec![], 1..=3),
Err(SubstrateError::Custom(_))
));
}
}