Redo coordinator's Substrate scanner

coordinator/substrate/src/lib.rs

@@ -0,0 +1,109 @@
+#![cfg_attr(docsrs, feature(doc_auto_cfg))]
+#![doc = include_str!("../README.md")]
+#![deny(missing_docs)]
+
+use scale::{Encode, Decode};
+use borsh::{io, BorshSerialize, BorshDeserialize};
+
+use serai_client::{
+  primitives::{PublicKey, NetworkId},
+  validator_sets::primitives::ValidatorSet,
+};
+
+use serai_db::*;
+
+mod canonical;
+mod ephemeral;
+
+fn borsh_serialize_validators<W: io::Write>(
+  validators: &Vec<(PublicKey, u16)>,
+  writer: &mut W,
+) -> Result<(), io::Error> {
+  // This doesn't use `encode_to` as `encode_to` panics if the writer returns an error
+  writer.write_all(&validators.encode())
+}
+
+fn borsh_deserialize_validators<R: io::Read>(
+  reader: &mut R,
+) -> Result<Vec<(PublicKey, u16)>, io::Error> {
+  Decode::decode(&mut scale::IoReader(reader)).map_err(io::Error::other)
+}
+
+/// The information for a new set.
+#[derive(Debug, BorshSerialize, BorshDeserialize)]
+pub struct NewSetInformation {
+  set: ValidatorSet,
+  serai_block: [u8; 32],
+  start_time: u64,
+  threshold: u16,
+  #[borsh(
+    serialize_with = "borsh_serialize_validators",
+    deserialize_with = "borsh_deserialize_validators"
+  )]
+  validators: Vec<(PublicKey, u16)>,
+  evrf_public_keys: Vec<([u8; 32], Vec<u8>)>,
+}
+
+mod _public_db {
+  use serai_client::{primitives::NetworkId, validator_sets::primitives::ValidatorSet};
+
+  use serai_db::*;
+
+  use crate::NewSetInformation;
+
+  db_channel!(
+    CoordinatorSubstrate {
+      // Canonical messages to send to the processor
+      Canonical: (network: NetworkId) -> messages::substrate::CoordinatorMessage,
+
+      // Relevant new set, from an ephemeral event stream
+      NewSet: () -> NewSetInformation,
+      // Relevant sign slash report, from an ephemeral event stream
+      SignSlashReport: () -> ValidatorSet,
+    }
+  );
+}
+
+/// The canonical event stream.
+pub struct Canonical;
+impl Canonical {
+  pub(crate) fn send(
+    txn: &mut impl DbTxn,
+    network: NetworkId,
+    msg: &messages::substrate::CoordinatorMessage,
+  ) {
+    _public_db::Canonical::send(txn, network, msg);
+  }
+  /// Try to receive a canonical event, returning `None` if there is none to receive.
+  pub fn try_recv(
+    txn: &mut impl DbTxn,
+    network: NetworkId,
+  ) -> Option<messages::substrate::CoordinatorMessage> {
+    _public_db::Canonical::try_recv(txn, network)
+  }
+}
+
+/// The channel for new set events emitted by an ephemeral event stream.
+pub struct NewSet;
+impl NewSet {
+  pub(crate) fn send(txn: &mut impl DbTxn, msg: &NewSetInformation) {
+    _public_db::NewSet::send(txn, msg);
+  }
+  /// Try to receive a new set's information, returning `None` if there is none to receive.
+  pub fn try_recv(txn: &mut impl DbTxn) -> Option<NewSetInformation> {
+    _public_db::NewSet::try_recv(txn)
+  }
+}
+
+/// The channel for notifications to sign a slash report, as emitted by an ephemeral event stream.
+pub struct SignSlashReport;
+impl SignSlashReport {
+  pub(crate) fn send(txn: &mut impl DbTxn, set: &ValidatorSet) {
+    _public_db::SignSlashReport::send(txn, set);
+  }
+  /// Try to receive a notification to sign a slash report, returning `None` if there is none to
+  /// receive.
+  pub fn try_recv(txn: &mut impl DbTxn) -> Option<ValidatorSet> {
+    _public_db::SignSlashReport::try_recv(txn)
+  }
+}