fix(derive): impl sidecar fetching and fix c-kzg online feat flag

crates/derive/Cargo.toml

@@ -27,7 +27,7 @@ miniz_oxide = { version = "0.7.2" }
 lru = "0.12.3"
 spin = { version = "0.9.8", features = ["mutex"] }
 c-kzg = { version = "1.0.0", default-features = false, optional = true }
-sha2 = { version = "0.10", default-features = false }
+sha2 = { version = "0.10", default-features = false, optional = true }
 
 # `serde` feature dependencies
 serde = { version = "1.0.197", default-features = false, features = ["derive"], optional = true }
@@ -46,11 +46,14 @@ alloy-rpc-client = { git = "https://github.com/alloy-rs/alloy", rev = "e3f2f07",
 
 [features]
 default = ["serde", "k256"]
-serde = ["dep:serde", "alloy-primitives/serde", "alloy-consensus/serde", "op-alloy-consensus/serde", "c-kzg/serde"]
+serde = ["dep:serde", "alloy-primitives/serde", "alloy-consensus/serde", "op-alloy-consensus/serde"]
 k256 = ["alloy-primitives/k256", "alloy-consensus/k256", "op-alloy-consensus/k256"]
 online = [
+  "dep:c-kzg",
+  "dep:sha2",
   "dep:alloy-provider",
   "dep:alloy-transport-http",
   "dep:reqwest",
-  "alloy-consensus/serde"
+  "alloy-consensus/serde",
+  "c-kzg/serde",
 ]

crates/derive/src/online/beacon_client.rs

@@ -3,7 +3,7 @@
 use crate::types::{
     APIConfigResponse, APIGenesisResponse, APIGetBlobSidecarsResponse, IndexedBlobHash,
 };
-use alloc::{boxed::Box, string::String, vec::Vec};
+use alloc::{boxed::Box, string::String};
 use alloy_provider::Provider;
 use alloy_transport_http::Http;
 use async_trait::async_trait;
@@ -40,7 +40,7 @@ pub trait BeaconClient {
         &self,
         fetch_all_sidecars: bool,
         slot: u64,
-        hashes: Vec<IndexedBlobHash>,
+        hashes: &[IndexedBlobHash],
     ) -> anyhow::Result<APIGetBlobSidecarsResponse>;
 }
 
@@ -76,7 +76,7 @@ impl<T: Provider<Http<Client>> + Send> BeaconClient for OnlineBeaconClient<T> {
         &self,
         fetch_all_sidecars: bool,
         slot: u64,
-        hashes: Vec<IndexedBlobHash>,
+        hashes: &[IndexedBlobHash],
     ) -> anyhow::Result<APIGetBlobSidecarsResponse> {
         let method = alloc::format!("{}{}", SIDECARS_METHOD_PREFIX, slot);
         self.inner

crates/derive/src/online/blob_provider.rs

@@ -60,6 +60,8 @@ impl From<anyhow::Error> for OnlineBlobProviderError {
 pub struct OnlineBlobProvider<T: Provider<Http<Client>>, B: BeaconClient, S: SlotDerivation> {
     /// The inner Ethereum JSON-RPC provider.
     _inner: T,
+    /// Whether to fetch all sidecars.
+    fetch_all_sidecars: bool,
     /// The Beacon API client.
     beacon_client: B,
     /// Beacon Genesis time used for the time to slot conversion.
@@ -78,11 +80,19 @@ impl<T: Provider<Http<Client>>, B: BeaconClient, S: SlotDerivation> OnlineBlobPr
     /// provided.
     pub fn new(
         _inner: T,
+        fetch_all_sidecars: bool,
         beacon_client: B,
         genesis_time: Option<u64>,
         slot_interval: Option<u64>,
     ) -> Self {
-        Self { _inner, beacon_client, genesis_time, slot_interval, _slot_derivation: PhantomData }
+        Self {
+            _inner,
+            fetch_all_sidecars,
+            beacon_client,
+            genesis_time,
+            slot_interval,
+            _slot_derivation: PhantomData,
+        }
     }
 
     /// Loads the beacon genesis and config spec
@@ -102,10 +112,14 @@ impl<T: Provider<Http<Client>>, B: BeaconClient, S: SlotDerivation> OnlineBlobPr
     /// Fetches blob sidecars for the given slot and blob hashes.
     pub async fn fetch_sidecars(
         &self,
-        _slot: u64,
-        _hashes: &[IndexedBlobHash],
+        slot: u64,
+        hashes: &[IndexedBlobHash],
     ) -> Result<Vec<APIBlobSidecar>, OnlineBlobProviderError> {
-        unimplemented!("fetching blob sidecars is not implemented");
+        self.beacon_client
+            .beacon_blob_side_cars(self.fetch_all_sidecars, slot, hashes)
+            .await
+            .map(|r| r.data)
+            .map_err(|e| e.into())
     }
 
     /// Fetches blob sidecars that were confirmed in the specified L1 block with the given indexed
@@ -250,7 +264,7 @@ mod tests {
         let (provider, _anvil) = spawn_anvil();
         let beacon_client = MockBeaconClient::default();
         let mut blob_provider: OnlineBlobProvider<_, _, SimpleSlotDerivation> =
-            OnlineBlobProvider::new(provider, beacon_client, None, None);
+            OnlineBlobProvider::new(provider, true, beacon_client, None, None);
         let block_ref = BlockInfo::default();
         let blob_hashes = Vec::new();
         let result = blob_provider.get_blob_sidecars(&block_ref, &blob_hashes).await;

crates/derive/src/online/test_utils.rs

@@ -4,7 +4,7 @@ use super::BeaconClient;
 use crate::types::{
     APIConfigResponse, APIGenesisResponse, APIGetBlobSidecarsResponse, IndexedBlobHash,
 };
-use alloc::{boxed::Box, string::String, vec::Vec};
+use alloc::{boxed::Box, string::String};
 use alloy_node_bindings::{Anvil, AnvilInstance};
 use alloy_provider::{network::Ethereum, ReqwestProvider};
 use alloy_rpc_client::RpcClient;
@@ -58,7 +58,7 @@ impl BeaconClient for MockBeaconClient {
         &self,
         _fetch_all_sidecars: bool,
         _slot: u64,
-        _hashes: Vec<IndexedBlobHash>,
+        _hashes: &[IndexedBlobHash],
     ) -> anyhow::Result<APIGetBlobSidecarsResponse> {
         self.blob_sidecars.clone().ok_or_else(|| anyhow::anyhow!("blob_sidecars not set"))
     }

crates/derive/src/types/mod.rs

@@ -37,7 +37,9 @@ pub use payload::{
     L2ExecutionPayload, L2ExecutionPayloadEnvelope, PAYLOAD_MEM_FIXED_COST, PAYLOAD_TX_MEM_OVERHEAD,
 };
 
+#[cfg(feature = "online")]
 mod kzg;
+#[cfg(feature = "online")]
 pub use kzg::{G1Points, G2Points, G1_POINTS, G2_POINTS};
 
 mod block;

crates/derive/src/types/sidecar.rs

@@ -1,10 +1,15 @@
 //! Contains sidecar types for blobs.
 
-use crate::types::{Blob, G1_POINTS, G2_POINTS};
+use crate::types::Blob;
+#[cfg(feature = "online")]
+use crate::types::{G1_POINTS, G2_POINTS};
 use alloc::{string::String, vec::Vec};
 use alloy_primitives::FixedBytes;
+#[cfg(feature = "online")]
 use c_kzg::{Bytes48, KzgProof, KzgSettings};
+#[cfg(feature = "online")]
 use sha2::{Digest, Sha256};
+#[cfg(feature = "online")]
 use tracing::warn;
 
 /// KZG Proof Size
@@ -14,6 +19,7 @@ pub const KZG_PROOF_SIZE: usize = 48;
 pub const KZG_COMMITMENT_SIZE: usize = 48;
 
 /// The versioned hash version for KZG.
+#[cfg(feature = "online")]
 pub(crate) const VERSIONED_HASH_VERSION_KZG: u8 = 0x01;
 
 /// A blob sidecar.
@@ -34,6 +40,7 @@ pub struct BlobSidecar {
 
 impl BlobSidecar {
     /// Verifies the blob kzg proof.
+    #[cfg(feature = "online")]
     pub fn verify_blob_kzg_proof(&self) -> anyhow::Result<bool> {
         let how = |e: c_kzg::Error| anyhow::anyhow!(e);
         let blob = c_kzg::Blob::from_bytes(self.blob.as_slice()).map_err(how)?;
@@ -50,6 +57,7 @@ impl BlobSidecar {
     }
 
     /// `VERSIONED_HASH_VERSION_KZG ++ sha256(commitment)[1..]`
+    #[cfg(feature = "online")]
     pub fn to_kzg_versioned_hash(&self) -> [u8; 32] {
         let commitment = self.kzg_commitment.as_slice();
         let mut hash: [u8; 32] = Sha256::digest(commitment).into();