Add stake table endpoint

sequencer/api/node.toml

@@ -0,0 +1,8 @@
+[route.stake_table_current]
+PATH = ["stake-table/current"]
+DOC = "Get the stake table for the current epoch"
+
+[route.stake_table]
+PATH = ["stake-table/:epoch_number"]
+":epoch_number" = "Integer"
+DOC = "Get the stake table for the given epoch"

sequencer/src/api.rs

@@ -5,7 +5,7 @@ use async_lock::RwLock;
 use async_once_cell::Lazy;
 use async_trait::async_trait;
 use committable::{Commitment, Committable};
-use data_source::{CatchupDataSource, SubmitDataSource};
+use data_source::{CatchupDataSource, StakeTableDataSource, SubmitDataSource};
 use derivative::Derivative;
 use espresso_types::{
     retain_accounts, v0::traits::SequencerPersistence, v0_3::ChainConfig, AccountQueryData,
@@ -26,9 +26,14 @@ use hotshot_types::{
     event::Event,
     light_client::StateSignatureRequestBody,
     network::NetworkConfig,
-    traits::{network::ConnectedNetwork, node_implementation::Versions, ValidatedState as _},
+    traits::{
+        network::ConnectedNetwork,
+        node_implementation::{NodeType, Versions},
+        ValidatedState as _,
+    },
     utils::{View, ViewInner},
 };
+use hotshot_types::{stake_table::StakeTableEntry, traits::election::Membership};
 use jf_merkle_tree::MerkleTreeScheme;
 use std::sync::Arc;
 
@@ -157,6 +162,43 @@ impl<N: ConnectedNetwork<PubKey>, D: Send + Sync, V: Versions, P: SequencerPersi
     }
 }
 
+impl<N: ConnectedNetwork<PubKey>, D: Sync, V: Versions, P: SequencerPersistence>
+    StakeTableDataSource<SeqTypes> for StorageState<N, P, D, V>
+{
+    /// Get the stake table for a given epoch or the current epoch if not provided
+    async fn get_stake_table(
+        &self,
+        epoch: Option<<SeqTypes as NodeType>::Epoch>,
+    ) -> Vec<StakeTableEntry<<SeqTypes as NodeType>::SignatureKey>> {
+        self.as_ref().get_stake_table(epoch).await
+    }
+}
+
+impl<N: ConnectedNetwork<PubKey>, V: Versions, P: SequencerPersistence>
+    StakeTableDataSource<SeqTypes> for ApiState<N, P, V>
+{
+    /// Get the stake table for a given epoch or the current epoch if not provided
+    async fn get_stake_table(
+        &self,
+        epoch: Option<<SeqTypes as NodeType>::Epoch>,
+    ) -> Vec<StakeTableEntry<<SeqTypes as NodeType>::SignatureKey>> {
+        // Get the epoch from the argument or the current epoch if not provided
+        let epoch = if let Some(epoch) = epoch {
+            epoch
+        } else {
+            self.consensus().await.read().await.cur_epoch().await
+        };
+
+        self.consensus()
+            .await
+            .read()
+            .await
+            .memberships
+            .quorum_membership
+            .stake_table(epoch)
+    }
+}
+
 impl<N: ConnectedNetwork<PubKey>, V: Versions, P: SequencerPersistence> SubmitDataSource<N, P>
     for ApiState<N, P, V>
 {

sequencer/src/api/data_source.rs

@@ -16,16 +16,18 @@ use hotshot_query_service::{
     node::NodeDataSource,
     status::StatusDataSource,
 };
-use hotshot_types::network::{
-    BuilderType, CombinedNetworkConfig, Libp2pConfig, RandomBuilderConfig,
-};
 use hotshot_types::{
     data::ViewNumber,
     light_client::StateSignatureRequestBody,
     network::NetworkConfig,
+    stake_table::StakeTableEntry,
     traits::{network::ConnectedNetwork, node_implementation::Versions},
     HotShotConfig, PeerConfig, ValidatorConfig,
 };
+use hotshot_types::{
+    network::{BuilderType, CombinedNetworkConfig, Libp2pConfig, RandomBuilderConfig},
+    traits::node_implementation::NodeType,
+};
 use serde::{Deserialize, Serialize};
 use tide_disco::Url;
 use vec1::Vec1;
@@ -114,6 +116,14 @@ pub(crate) trait NodeStateDataSource {
     fn node_state(&self) -> impl Send + Future<Output = &NodeState>;
 }
 
+pub(crate) trait StakeTableDataSource<T: NodeType> {
+    /// Get the stake table for a given epoch or the current epoch if not provided
+    fn get_stake_table(
+        &self,
+        epoch: Option<<T as NodeType>::Epoch>,
+    ) -> impl Send + Future<Output = Vec<StakeTableEntry<T::SignatureKey>>>;
+}
+
 pub(crate) trait CatchupDataSource: Sync {
     /// Get the state of the requested `account`.
     ///

sequencer/src/api/endpoints.rs

@@ -9,7 +9,6 @@ use anyhow::Result;
 use committable::Committable;
 use espresso_types::{FeeAccount, FeeMerkleTree, NamespaceId, NsProof, PubKey, Transaction};
 use futures::{try_join, FutureExt};
-use hotshot_query_service::merklized_state::Snapshot;
 use hotshot_query_service::{
     availability::{self, AvailabilityDataSource, CustomSnafu, FetchBlockSnafu},
     explorer::{self, ExplorerDataSource},
@@ -18,8 +17,9 @@ use hotshot_query_service::{
     },
     node, ApiState, Error,
 };
+use hotshot_query_service::{merklized_state::Snapshot, node::NodeDataSource};
 use hotshot_types::{
-    data::ViewNumber,
+    data::{EpochNumber, ViewNumber},
     traits::{
         network::ConnectedNetwork,
         node_implementation::{ConsensusTime, Versions},
@@ -30,12 +30,12 @@ use serde::{de::Error as _, Deserialize, Serialize};
 use snafu::OptionExt;
 use tagged_base64::TaggedBase64;
 use tide_disco::{method::ReadState, Api, Error as _, StatusCode};
-use vbs::version::StaticVersionType;
+use vbs::version::{StaticVersion, StaticVersionType};
 
 use super::{
     data_source::{
         CatchupDataSource, HotShotConfigDataSource, NodeStateDataSource, SequencerDataSource,
-        StateSignatureDataSource, SubmitDataSource,
+        StakeTableDataSource, StateSignatureDataSource, SubmitDataSource,
     },
     StorageState,
 };
@@ -174,18 +174,47 @@ where
     Ok(api)
 }
 
-type NodeApi<N, P, D, V, ApiVer> = Api<AvailState<N, P, D, V>, node::Error, ApiVer>;
-
-pub(super) fn node<N, P, D, V: Versions>() -> Result<NodeApi<N, P, D, V, SequencerApiVersion>>
+pub(super) fn node<S>() -> Result<Api<S, node::Error, StaticVersion<0, 1>>>
 where
-    N: ConnectedNetwork<PubKey>,
-    D: SequencerDataSource + Send + Sync + 'static,
-    P: SequencerPersistence,
+    S: 'static + Send + Sync + ReadState,
+    <S as ReadState>::State:
+        Send + Sync + StakeTableDataSource<SeqTypes> + NodeDataSource<SeqTypes>,
 {
-    let api = node::define_api::<AvailState<N, P, D, V>, SeqTypes, _>(
-        &Default::default(),
-        SequencerApiVersion::instance(),
-    )?;
+    // Extend the base API
+    let mut options = node::Options::default();
+    let extension = toml::from_str(include_str!("../../api/node.toml"))?;
+    options.extensions.push(extension);
+
+    // Create the base API with our extensions
+    let mut api = node::define_api::<S, SeqTypes, _>(&options, SequencerApiVersion::instance())?;
+
+    // Tack on the application logic
+    api.at("stake_table", |req, state| {
+        async move {
+            // Try to get the epoch from the request. If this fails, error
+            // as it was probably a mistake
+            let epoch = EpochNumber::new(req.integer_param("epoch_number").map_err(|_| {
+                hotshot_query_service::node::Error::Custom {
+                    message: "Epoch number is required".to_string(),
+                    status: StatusCode::BAD_REQUEST,
+                }
+            })?);
+
+            Ok(state
+                .read(|state| state.get_stake_table(Some(epoch)).boxed())
+                .await)
+        }
+        .boxed()
+    })?
+    .at("stake_table_current", |_, state| {
+        async move {
+            Ok(state
+                .read(|state| state.get_stake_table(None).boxed())
+                .await)
+        }
+        .boxed()
+    })?;
+
     Ok(api)
 }
 pub(super) fn submit<N, P, S, ApiVer: StaticVersionType + 'static>() -> Result<Api<S, Error, ApiVer>>