chore: Adds ZenithEthBundle type to bundle module

Cargo.toml

@@ -11,17 +11,14 @@ repository = "https://github.com/init4tech/zenith"
 license = "AGPL-3.0"
 
 [dependencies]
+alloy = { version = "=0.7.3", features = ["full", "json-rpc", "signer-aws", "rpc-types-mev"] }
 alloy-primitives = { version = "0.8.11", features = ["serde", "tiny-keccak"] }
 alloy-sol-types = { version = "0.8.11", features = ["json"] }
-
 alloy-rlp = { version = "0.3.4" }
-
-alloy = { version = "=0.7.3", features = ["full", "json-rpc", "signer-aws"] }
 alloy-contract = { version = "=0.7.3", features = ["pubsub"] }
 
 serde = { version = "1.0.197", features = ["derive"] }
 
 [dev-dependencies]
 serde_json = "1.0.94"
 tokio = { version = "1.37.0", features = ["macros"] }
-

src/bundle.rs

@@ -0,0 +1,278 @@
+use alloy::{
+    eips::{eip2718::Encodable2718, BlockNumberOrTag},
+    rpc::types::mev::{EthCallBundle, EthCallBundleResponse, EthSendBundle},
+};
+use alloy_primitives::{keccak256, Address, Bytes, B256, U256};
+use serde::{Deserialize, Serialize};
+use std::collections::BTreeMap;
+
+use crate::SignedOrder;
+
+/// Wraps a flashbots style EthSendBundle with host fills to make a Zenith compatible bundle
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ZenithEthBundle {
+    /// The bundle of transactions to simulate. Same structure as a Flashbots [EthSendBundle] bundle.
+    /// see <https://github.com/alloy-rs/alloy/blob/main/crates/rpc-types-mev/src/eth_calls.rs#L121-L139>
+    #[serde(flatten)]
+    pub bundle: EthSendBundle,
+    /// Host fills to be applied with the bundle, represented as a signed permit2 order.
+    pub host_fills: Option<SignedOrder>,
+}
+
+impl ZenithEthBundle {
+    /// Returns the transactions in this bundle.
+    pub fn txs(&self) -> &[Bytes] {
+        &self.bundle.txs
+    }
+
+    /// Returns the block number for this bundle.
+    pub const fn block_number(&self) -> u64 {
+        self.bundle.block_number
+    }
+
+    /// Returns the minimum timestamp for this bundle.
+    pub const fn min_timestamp(&self) -> Option<u64> {
+        self.bundle.min_timestamp
+    }
+
+    /// Returns the maximum timestamp for this bundle.
+    pub const fn max_timestamp(&self) -> Option<u64> {
+        self.bundle.max_timestamp
+    }
+
+    /// Returns the reverting tx hashes for this bundle.
+    pub fn reverting_tx_hashes(&self) -> &[B256] {
+        self.bundle.reverting_tx_hashes.as_slice()
+    }
+
+    /// Returns the replacement uuid for this bundle.
+    pub fn replacement_uuid(&self) -> Option<&str> {
+        self.bundle.replacement_uuid.as_deref()
+    }
+}
+
+/// Response for `zenith_sendBundle`
+#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ZenithEthBundleResponse {
+    /// The bundle hash of the sent bundle.
+    ///
+    /// This is calculated as keccak256(tx_hashes) where tx_hashes are the concatenated transaction hashes.
+    pub bundle_hash: B256,
+}
+
+/// Bundle of transactions for `zenith_callBundle`
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "camelCase")]
+pub struct ZenithCallBundle {
+    /// The bundle of transactions to simulate. Same structure as a Flashbots [EthCallBundle] bundle.
+    /// see <https://github.com/alloy-rs/alloy/blob/main/crates/rpc-types-mev/src/eth_calls.rs#L13-L33>
+    #[serde(flatten)]
+    pub bundle: EthCallBundle,
+    /// Host fills to be applied to the bundle for simulation. The mapping corresponds
+    /// to asset => user => amount.
+    pub host_fills: BTreeMap<Address, BTreeMap<Address, U256>>,
+}
+
+impl ZenithCallBundle {
+    /// Returns the host fills for this bundle.
+    pub const fn host_fills(&self) -> &BTreeMap<Address, BTreeMap<Address, U256>> {
+        &self.host_fills
+    }
+
+    /// Returns the transactions in this bundle.
+    pub fn txs(&self) -> &[Bytes] {
+        &self.bundle.txs
+    }
+
+    /// Returns the block number for this bundle.
+    pub const fn block_number(&self) -> u64 {
+        self.bundle.block_number
+    }
+
+    /// Returns the state block number for this bundle.
+    pub const fn state_block_number(&self) -> BlockNumberOrTag {
+        self.bundle.state_block_number
+    }
+
+    /// Returns the timestamp for this bundle.
+    pub const fn timestamp(&self) -> Option<u64> {
+        self.bundle.timestamp
+    }
+
+    /// Returns the gas limit for this bundle.
+    pub const fn gas_limit(&self) -> Option<u64> {
+        self.bundle.gas_limit
+    }
+
+    /// Returns the difficulty for this bundle.
+    pub const fn difficulty(&self) -> Option<U256> {
+        self.bundle.difficulty
+    }
+
+    /// Returns the base fee for this bundle.
+    pub const fn base_fee(&self) -> Option<u128> {
+        self.bundle.base_fee
+    }
+
+    /// Creates a new bundle from the given [`Encodable2718`] transactions.
+    pub fn from_2718_and_host_fills<I, T>(
+        txs: I,
+        host_fills: BTreeMap<Address, BTreeMap<Address, U256>>,
+    ) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Encodable2718,
+    {
+        Self::from_raw_txs_and_host_fills(txs.into_iter().map(|tx| tx.encoded_2718()), host_fills)
+    }
+
+    /// Creates a new bundle with the given transactions and host fills.
+    pub fn from_raw_txs_and_host_fills<I, T>(
+        txs: I,
+        host_fills: BTreeMap<Address, BTreeMap<Address, U256>>,
+    ) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<Bytes>,
+    {
+        Self {
+            bundle: EthCallBundle {
+                txs: txs.into_iter().map(Into::into).collect(),
+                ..Default::default()
+            },
+            host_fills,
+        }
+    }
+
+    /// Adds an [`Encodable2718`] transaction to the bundle.
+    pub fn append_2718_tx(self, tx: impl Encodable2718) -> Self {
+        self.append_raw_tx(tx.encoded_2718())
+    }
+
+    /// Adds an EIP-2718 envelope to the bundle.
+    pub fn append_raw_tx(mut self, tx: impl Into<Bytes>) -> Self {
+        self.bundle.txs.push(tx.into());
+        self
+    }
+
+    /// Adds multiple [`Encodable2718`] transactions to the bundle.
+    pub fn extend_2718_txs<I, T>(self, tx: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Encodable2718,
+    {
+        self.extend_raw_txs(tx.into_iter().map(|tx| tx.encoded_2718()))
+    }
+
+    /// Adds multiple calls to the block.
+    pub fn extend_raw_txs<I, T>(mut self, txs: I) -> Self
+    where
+        I: IntoIterator<Item = T>,
+        T: Into<Bytes>,
+    {
+        self.bundle.txs.extend(txs.into_iter().map(Into::into));
+        self
+    }
+
+    /// Sets the block number for the bundle.
+    pub const fn with_block_number(mut self, block_number: u64) -> Self {
+        self.bundle.block_number = block_number;
+        self
+    }
+
+    /// Sets the state block number for the bundle.
+    pub fn with_state_block_number(
+        mut self,
+        state_block_number: impl Into<BlockNumberOrTag>,
+    ) -> Self {
+        self.bundle.state_block_number = state_block_number.into();
+        self
+    }
+
+    /// Sets the timestamp for the bundle.
+    pub const fn with_timestamp(mut self, timestamp: u64) -> Self {
+        self.bundle.timestamp = Some(timestamp);
+        self
+    }
+
+    /// Sets the gas limit for the bundle.
+    pub const fn with_gas_limit(mut self, gas_limit: u64) -> Self {
+        self.bundle.gas_limit = Some(gas_limit);
+        self
+    }
+
+    /// Sets the difficulty for the bundle.
+    pub const fn with_difficulty(mut self, difficulty: U256) -> Self {
+        self.bundle.difficulty = Some(difficulty);
+        self
+    }
+
+    /// Sets the base fee for the bundle.
+    pub const fn with_base_fee(mut self, base_fee: u128) -> Self {
+        self.bundle.base_fee = Some(base_fee);
+        self
+    }
+
+    /// Make a bundle hash from the given deserialized transaction array and host fills from this bundle.
+    /// The hash is calculated as keccak256(tx_preimage + host_preimage).
+    /// The tx_preimage is calculated as `keccak(tx_hash1 + tx_hash2 + ... + tx_hashn)`.
+    /// The host_preimage is calculated as
+    /// `keccak(NUM_OF_ASSETS_LE + asset1 + NUM_OF_FILLS_LE + asset1_user1 + user1_amount2 + ... + asset1_usern + asset1_amountn + ...)`.
+    /// For the number of users/fills and amounts in the host_preimage, the amounts are serialized as little-endian U256 slice.
+    pub fn bundle_hash(&self) -> B256 {
+        let mut hasher = alloy_primitives::Keccak256::new();
+
+        // Concatenate the transaction hashes, to then hash them. This is the tx_preimage.
+        for tx in self.bundle.txs.iter() {
+            // Calculate the tx hash (keccak256(encoded_signed_tx)) and append it to the tx_bytes.
+            hasher.update(keccak256(tx).as_slice());
+        }
+        let tx_preimage = hasher.finalize();
+
+        // Now, let's build the host_preimage. We do it in steps:
+        // 1. Prefix the number of assets, encoded as a little-endian U256 slice.
+        // 2. For each asset:
+        // 3. Concatenate the asset address.
+        // 4. Prefix the number of fills.
+        // 5. For each fill, concatenate the user and amount, the latter encoded as a little-endian U256 slice.
+        let mut hasher = alloy_primitives::Keccak256::new();
+
+        // Prefix the list of users with the number of assets.
+        hasher.update(U256::from(self.host_fills.len()).as_le_slice());
+
+        for (asset, fills) in self.host_fills.iter() {
+            // Concatenate the asset address.
+            hasher.update(asset.as_slice());
+
+            // Prefix the list of fills with the number of fills
+            hasher.update(U256::from(fills.len()).as_le_slice());
+
+            for (user, amount) in fills.iter() {
+                // Concatenate the user address and amount for each fill.
+                hasher.update(user.as_slice());
+                hasher.update(amount.as_le_slice());
+            }
+        }
+
+        // Hash the host pre-image.
+        let host_preimage = hasher.finalize();
+
+        let mut pre_image = alloy_primitives::Keccak256::new();
+        pre_image.update(tx_preimage.as_slice());
+        pre_image.update(host_preimage.as_slice());
+
+        // Hash both tx and host hashes to get the final bundle hash.
+        pre_image.finalize()
+    }
+}
+
+/// Response for `zenith_callBundle`
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, Default)]
+#[serde(rename_all = "camelCase")]
+pub struct ZenithCallBundleResponse {
+    /// The flattened "vanilla" response which comes from `eth_callBundle`
+    #[serde(flatten)]
+    pub response: EthCallBundleResponse,
+}

src/lib.rs

@@ -22,6 +22,11 @@ pub use block::{decode_txns, encode_txns, Alloy2718Coder, Coder, ZenithBlock, Ze
 mod orders;
 pub use orders::{AggregateOrders, SignedOrder};
 
+mod bundle;
+pub use bundle::{
+    ZenithCallBundle, ZenithCallBundleResponse, ZenithEthBundle, ZenithEthBundleResponse,
+};
+
 mod req;
 pub use req::SignRequest;