add optimistic block APIs to sequencer

Co-authored-by: Bharath <[email protected]>

charts/sequencer/Chart.yaml

@@ -20,7 +20,7 @@ version: 1.0.1
 # incremented each time you make changes to the application. Versions are not expected to
 # follow Semantic Versioning. They should reflect the version the application is using.
 # It is recommended to use it with quotes.
-appVersion: "1.0.0"
+appVersion: "1.0.1"
 
 dependencies:
   - name: sequencer-relayer

charts/sequencer/templates/configmaps.yaml

@@ -75,5 +75,6 @@ data:
   OTEL_SERVICE_NAME: "{{ tpl .Values.sequencer.otel.serviceName . }}"
   {{- if not .Values.global.dev }}
   {{- else }}
+  ASTRIA_SEQUENCER_NO_OPTIMISTIC_BLOCKS: "{{ not .Values.sequencer.optimisticBlockApis.enabled }}"
   {{- end }}
 ---

charts/sequencer/values.yaml

@@ -120,6 +120,8 @@ sequencer:
     tracesTimeout: 10
     otlpHeaders:
     traceHeaders:
+  optimisticBlockApis:
+    enabled: false
 
 cometbft:
   config:

crates/astria-core/src/sequencerblock/v1/mod.rs

@@ -1,5 +1,6 @@
 pub mod block;
 pub mod celestia;
+pub mod optimistic;
 
 pub use block::{
     RollupTransactions,

crates/astria-core/src/sequencerblock/v1/optimistic.rs

@@ -0,0 +1,83 @@
+use bytes::Bytes;
+
+use crate::{
+    generated::astria::sequencerblock::optimistic::v1alpha1 as raw,
+    Protobuf,
+};
+
+#[derive(Debug, thiserror::Error)]
+#[error(transparent)]
+pub struct SequencerBlockCommitError(SequencerBlockCommitErrorKind);
+
+impl SequencerBlockCommitError {
+    fn invalid_block_hash(len: usize) -> Self {
+        Self(SequencerBlockCommitErrorKind::InvalidBlockHash(len))
+    }
+}
+
+#[derive(Debug, thiserror::Error)]
+enum SequencerBlockCommitErrorKind {
+    #[error("invalid block hash length: {0}")]
+    InvalidBlockHash(usize),
+}
+
+#[derive(Clone, Debug)]
+pub struct SequencerBlockCommit {
+    height: u64,
+    block_hash: [u8; 32],
+}
+
+impl SequencerBlockCommit {
+    #[must_use]
+    pub fn new(height: u64, block_hash: [u8; 32]) -> Self {
+        Self {
+            height,
+            block_hash,
+        }
+    }
+
+    #[must_use]
+    pub fn height(&self) -> u64 {
+        self.height
+    }
+
+    #[must_use]
+    pub fn block_hash(&self) -> &[u8; 32] {
+        &self.block_hash
+    }
+}
+
+impl From<SequencerBlockCommit> for raw::SequencerBlockCommit {
+    fn from(value: SequencerBlockCommit) -> Self {
+        value.to_raw()
+    }
+}
+
+impl Protobuf for SequencerBlockCommit {
+    type Error = SequencerBlockCommitError;
+    type Raw = raw::SequencerBlockCommit;
+
+    fn try_from_raw_ref(raw: &Self::Raw) -> Result<Self, Self::Error> {
+        let Self::Raw {
+            height,
+            block_hash,
+        } = raw;
+
+        let block_hash = block_hash
+            .as_ref()
+            .try_into()
+            .map_err(|_| SequencerBlockCommitError::invalid_block_hash(block_hash.len()))?;
+
+        Ok(SequencerBlockCommit {
+            height: *height,
+            block_hash,
+        })
+    }
+
+    fn to_raw(&self) -> Self::Raw {
+        raw::SequencerBlockCommit {
+            height: self.height(),
+            block_hash: Bytes::copy_from_slice(self.block_hash()),
+        }
+    }
+}

crates/astria-sequencer/Cargo.toml

@@ -64,6 +64,7 @@ tendermint-proto = { workspace = true }
 tendermint = { workspace = true }
 thiserror = { workspace = true }
 tokio = { workspace = true, features = ["rt", "tracing"] }
+tokio-util = { workspace = true, features = ["rt"] }
 tonic = { workspace = true }
 tracing = { workspace = true }
 

crates/astria-sequencer/local.env.example

@@ -33,6 +33,9 @@ ASTRIA_SEQUENCER_METRICS_HTTP_LISTENER_ADDR="127.0.0.1:9000"
 # `ASTRIA_SEQUENCER_FORCE_STDOUT` is set to `true`.
 ASTRIA_SEQUENCER_PRETTY_PRINT=false
 
+# Disables streaming optimistic blocks to clients.
+ASTRIA_SEQUENCER_NO_OPTIMISTIC_BLOCKS=false
+
 # If set to any non-empty value removes ANSI escape characters from the pretty
 # printed output. Note that this does nothing unless `ASTRIA_SEQUENCER_PRETTY_PRINT`
 # is set to `true`.

crates/astria-sequencer/src/app/event_bus.rs

@@ -0,0 +1,158 @@
+use std::sync::Arc;
+
+use astria_core::sequencerblock::v1::SequencerBlock;
+use astria_eyre::eyre::WrapErr as _;
+use tendermint::abci::request::FinalizeBlock;
+use tokio::sync::watch::{
+    Receiver,
+    Sender,
+};
+use tokio_util::sync::CancellationToken;
+
+/// `EventReceiver` contains the receiver side of the events sent by the Sequencer App.
+/// The listeners of the events can receive the latest value of the event by calling the
+/// `receive` method.
+#[derive(Clone)]
+pub(crate) struct EventReceiver<T> {
+    // The receiver side of the watch which is read for the latest value of the event.
+    // We receive an Option over T because the sender side of the watch is designed to send
+    // Option values. This allows the sender value to send objects which do not have a `Default`
+    // implementation.
+    inner: Receiver<Option<T>>,
+    // To signal subscribers that the event bus is initialized, i.e. that the value in `sender` was
+    // set.
+    is_init: CancellationToken,
+}
+
+impl<T> EventReceiver<T>
+where
+    T: Clone,
+{
+    // Marks the current message in the receiver end of the watch as seen.
+    // This is useful in situations where we want to ignore the current value of the watch
+    // and wait for the next value.
+    pub(crate) fn mark_latest_event_as_seen(&mut self) {
+        self.inner.mark_unchanged();
+    }
+
+    // Returns the latest value of the event, waiting for the value to change if it hasn't already.
+    pub(crate) async fn receive(&mut self) -> astria_eyre::Result<T> {
+        // This will get resolved when the sender side of the watch is initialized by sending
+        // the first value. We wait till the sender side of the watch has initialized the watch.
+        // Once the sender side has been initialized, it will get resolved immediately.
+        self.is_init.cancelled().await;
+        // We want to only receive the latest value through the receiver, so we wait for the
+        // current value in the watch to change before we return it.
+        self.inner
+            .changed()
+            .await
+            .wrap_err("error waiting for latest event")?;
+        Ok(self.inner.borrow_and_update().clone().expect(
+            "events must be set after is_init is triggered; this means an invariant was violated",
+        ))
+    }
+}
+
+/// `EventSender` contains the sender side of the events sent by the Sequencer App.
+/// At any given time, it sends the latest value of the event.
+struct EventSender<T> {
+    // A watch channel that is always starts unset. Once set, the `is_init` token is cancelled
+    // and value in the channel will never be unset.
+    inner: Sender<Option<T>>,
+    // To signal subscribers that the event bus is initialized, i.e. that the value in `sender` was
+    // set.
+    is_init: CancellationToken,
+}
+
+impl<T> EventSender<T> {
+    fn new() -> Self {
+        let (sender, _) = tokio::sync::watch::channel(None);
+        Self {
+            inner: sender,
+            is_init: CancellationToken::new(),
+        }
+    }
+
+    // Returns a `EventReceiver` object that contains the receiver side of the watch which can be
+    // used to receive the latest value of the event.
+    fn subscribe(&self) -> EventReceiver<T> {
+        EventReceiver {
+            inner: self.inner.subscribe(),
+            is_init: self.is_init.clone(),
+        }
+    }
+
+    // Sends the event to all the subscribers.
+    fn send(&self, event: T) {
+        self.inner.send_replace(Some(event));
+        // after sending the first value, we resolve the is_init token to signal that the sender
+        // side of the watch is initialized. The receiver side can now start receiving valid
+        // values.
+        self.is_init.cancel();
+    }
+}
+
+/// `EventBusSubscription` contains [`EventReceiver`] of various events that can be subscribed.
+/// It can be cloned by various components in the sequencer app to receive events.
+#[derive(Clone)]
+pub(crate) struct EventBusSubscription {
+    process_proposal_blocks: EventReceiver<Arc<SequencerBlock>>,
+    finalized_blocks: EventReceiver<Arc<FinalizeBlock>>,
+}
+
+impl EventBusSubscription {
+    pub(crate) fn process_proposal_blocks(&mut self) -> EventReceiver<Arc<SequencerBlock>> {
+        self.process_proposal_blocks.clone()
+    }
+
+    pub(crate) fn finalized_blocks(&mut self) -> EventReceiver<Arc<FinalizeBlock>> {
+        self.finalized_blocks.clone()
+    }
+}
+
+/// The Sequencer `EventBus` is used to send and receive events between different components of the
+/// sequencer. Components of Sequencer can subscribe to the `EventBus` via the `subscribe` method
+/// which returns a [`EventBusSubscription`] objects that contains receivers of various events which
+/// are of type [`EventReceiver`].
+///
+/// The `EventBus` is implemented using [`tokio::sync::watch`] which allows for multiple receivers
+/// to receive the event at any given time.
+pub(super) struct EventBus {
+    // Sends a process proposal block event to the subscribers. The event is sent in the form of a
+    // sequencer block which is created during the process proposal block phase.
+    process_proposal_block_sender: EventSender<Arc<SequencerBlock>>,
+    // Sends a finalized block event to the subscribers. The event is sent in the form of the
+    // finalize block abci request.
+    finalized_block_sender: EventSender<Arc<FinalizeBlock>>,
+}
+
+impl EventBus {
+    pub(super) fn new() -> Self {
+        let process_proposal_block_sender = EventSender::new();
+        let finalized_block_sender = EventSender::new();
+
+        Self {
+            process_proposal_block_sender,
+            finalized_block_sender,
+        }
+    }
+
+    // Returns a `EventBusSubscription` object that contains receivers of various events that can
+    // be subscribed to.
+    pub(crate) fn subscribe(&self) -> EventBusSubscription {
+        EventBusSubscription {
+            process_proposal_blocks: self.process_proposal_block_sender.subscribe(),
+            finalized_blocks: self.finalized_block_sender.subscribe(),
+        }
+    }
+
+    // Sends a process proposal block event to the subscribers.
+    pub(super) fn send_process_proposal_block(&self, sequencer_block: Arc<SequencerBlock>) {
+        self.process_proposal_block_sender.send(sequencer_block);
+    }
+
+    // Sends a finalized block event to the subscribers.
+    pub(super) fn send_finalized_block(&self, sequencer_block_commit: Arc<FinalizeBlock>) {
+        self.finalized_block_sender.send(sequencer_block_commit);
+    }
+}