nautilus_blockchain/contracts/
base.rs

1// -------------------------------------------------------------------------------------------------
2//  Copyright (C) 2015-2026 Nautech Systems Pty Ltd. All rights reserved.
3//  https://nautechsystems.io
4//
5//  Licensed under the GNU Lesser General Public License Version 3.0 (the "License");
6//  You may not use this file except in compliance with the License.
7//  You may obtain a copy of the License at https://www.gnu.org/licenses/lgpl-3.0.en.html
8//
9//  Unless required by applicable law or agreed to in writing, software
10//  distributed under the License is distributed on an "AS IS" BASIS,
11//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12//  See the License for the specific language governing permissions and
13//  limitations under the License.
14// -------------------------------------------------------------------------------------------------
15
16use std::sync::Arc;
17
18use alloy::{primitives::Address, sol, sol_types::SolCall};
19use nautilus_core::hex;
20use nautilus_model::defi::validation::validate_address;
21
22use crate::rpc::{error::BlockchainRpcClientError, http::BlockchainHttpRpcClient};
23
24sol! {
25    #[sol(rpc)]
26    contract Multicall3 {
27        struct Call {
28            address target;
29            bytes callData;
30        }
31
32        struct Call3 {
33            address target;
34            bool allowFailure;
35            bytes callData;
36        }
37
38        struct Result {
39            bool success;
40            bytes returnData;
41        }
42
43        function aggregate3(Call3[] calldata calls) external payable returns (Result[] memory returnData);
44        function tryAggregate(bool requireSuccess, Call[] calldata calls) external payable returns (Result[] memory returnData);
45    }
46}
47
48/// Standard Multicall3 address (same on all EVM chains).
49pub const MULTICALL3_ADDRESS: &str = "0xcA11bde05977b3631167028862bE2a173976CA11";
50const DEFAULT_MULTICALL_CALLS_PER_RPC_REQUEST: u32 = 200;
51
52/// Base contract functionality for interacting with blockchain contracts.
53///
54/// This struct provides common RPC execution patterns that can be reused
55/// by specific contract implementations like ERC20, ERC721, etc.
56#[derive(Debug)]
57pub struct BaseContract {
58    /// The HTTP RPC client used to communicate with the blockchain node.
59    client: Arc<BlockchainHttpRpcClient>,
60    /// The Multicall3 contract address.
61    multicall_address: Address,
62    /// Maximum number of contract calls encoded into one Multicall RPC request.
63    multicall_calls_per_rpc_request: usize,
64}
65
66/// Represents a single contract call for batching in multicall.
67#[derive(Debug)]
68pub struct ContractCall {
69    /// The target contract address
70    pub target: Address,
71    /// Whether this call can fail without reverting the entire multicall.
72    pub allow_failure: bool,
73    /// The encoded call data.
74    pub call_data: Vec<u8>,
75}
76
77impl BaseContract {
78    /// Creates a new base contract interface with the specified RPC client.
79    ///
80    /// # Panics
81    ///
82    /// Panics if the multicall address is invalid (which should never happen with the hardcoded address).
83    #[must_use]
84    pub fn new(client: Arc<BlockchainHttpRpcClient>) -> Self {
85        Self::new_with_multicall_limit(client, DEFAULT_MULTICALL_CALLS_PER_RPC_REQUEST)
86    }
87
88    /// Creates a new base contract interface with an explicit Multicall request size.
89    ///
90    /// # Panics
91    ///
92    /// Panics if the multicall address is invalid (which should never happen with the hardcoded address).
93    #[must_use]
94    pub fn new_with_multicall_limit(
95        client: Arc<BlockchainHttpRpcClient>,
96        multicall_calls_per_rpc_request: u32,
97    ) -> Self {
98        let multicall_address =
99            validate_address(MULTICALL3_ADDRESS).expect("Invalid multicall address");
100        let multicall_calls_per_rpc_request = (multicall_calls_per_rpc_request as usize).max(1);
101
102        Self {
103            client,
104            multicall_address,
105            multicall_calls_per_rpc_request,
106        }
107    }
108
109    /// Gets a reference to the RPC client.
110    #[must_use]
111    pub const fn client(&self) -> &Arc<BlockchainHttpRpcClient> {
112        &self.client
113    }
114
115    /// Executes a single contract call and returns the raw response bytes.
116    ///
117    /// # Errors
118    ///
119    /// Returns an error if the RPC call fails or response decoding fails.
120    pub async fn execute_call(
121        &self,
122        contract_address: &Address,
123        call_data: &[u8],
124        block: Option<u64>,
125    ) -> Result<Vec<u8>, BlockchainRpcClientError> {
126        let rpc_request =
127            self.client
128                .construct_eth_call(&contract_address.to_string(), call_data, block);
129
130        let encoded_response = self
131            .client
132            .execute_rpc_call::<String>(rpc_request)
133            .await
134            .map_err(|e| BlockchainRpcClientError::ClientError(format!("RPC call failed: {e}")))?;
135
136        decode_hex_response(&encoded_response)
137    }
138
139    /// Executes multiple contract calls in a single multicall transaction.
140    ///
141    /// # Errors
142    ///
143    /// Returns an error if the multicall fails or decoding fails.
144    pub async fn execute_multicall(
145        &self,
146        calls: Vec<ContractCall>,
147        block: Option<u64>,
148    ) -> Result<Vec<Multicall3::Result>, BlockchainRpcClientError> {
149        if calls.is_empty() {
150            return Ok(Vec::new());
151        }
152
153        let mut results = Vec::with_capacity(calls.len());
154        for chunk in contract_call_chunks(&calls, self.multicall_calls_per_rpc_request) {
155            results.extend(self.execute_multicall_request(chunk, block).await?);
156        }
157        Ok(results)
158    }
159
160    async fn execute_multicall_request(
161        &self,
162        calls: &[ContractCall],
163        block: Option<u64>,
164    ) -> Result<Vec<Multicall3::Result>, BlockchainRpcClientError> {
165        // Convert to Multicall3 format.
166        let multicall_calls: Vec<Multicall3::Call> = calls
167            .iter()
168            .map(|call| Multicall3::Call {
169                target: call.target,
170                callData: call.call_data.clone().into(),
171            })
172            .collect();
173
174        let multicall_data = Multicall3::tryAggregateCall {
175            requireSuccess: false,
176            calls: multicall_calls,
177        }
178        .abi_encode();
179        let rpc_request = self.client.construct_eth_call(
180            &self.multicall_address.to_string(),
181            multicall_data.as_slice(),
182            block,
183        );
184
185        let encoded_response = self
186            .client
187            .execute_rpc_call::<String>(rpc_request)
188            .await
189            .map_err(|e| BlockchainRpcClientError::ClientError(format!("Multicall failed: {e}")))?;
190
191        let bytes = decode_hex_response(&encoded_response)?;
192        let results = Multicall3::tryAggregateCall::abi_decode_returns(&bytes).map_err(|e| {
193            BlockchainRpcClientError::AbiDecodingError(format!(
194                "Failed to decode multicall results: {e}"
195            ))
196        })?;
197
198        Ok(results)
199    }
200}
201
202/// Decodes a hexadecimal string response from a blockchain RPC call.
203///
204/// # Errors
205///
206/// Returns an `BlockchainRpcClientError::AbiDecodingError` if the hex decoding fails.
207pub fn decode_hex_response(encoded_response: &str) -> Result<Vec<u8>, BlockchainRpcClientError> {
208    // Remove the "0x" prefix if present
209    let encoded_str = encoded_response
210        .strip_prefix("0x")
211        .unwrap_or(encoded_response);
212    hex::decode(encoded_str).map_err(|e| {
213        BlockchainRpcClientError::AbiDecodingError(format!("Error decoding hex response: {e}"))
214    })
215}
216
217fn contract_call_chunks(
218    calls: &[ContractCall],
219    multicall_calls_per_rpc_request: usize,
220) -> std::slice::Chunks<'_, ContractCall> {
221    calls.chunks(multicall_calls_per_rpc_request.max(1))
222}
223
224#[cfg(test)]
225mod tests {
226    use alloy::primitives::address;
227    use rstest::rstest;
228
229    use super::*;
230
231    #[rstest]
232    fn contract_call_chunks_preserves_order_across_chunk_boundary() {
233        let target = address!("25b76A90E389bD644a29db919b136Dc63B174Ec7");
234        let calls: Vec<ContractCall> = (0u8..5)
235            .map(|value| ContractCall {
236                target,
237                allow_failure: true,
238                call_data: vec![value],
239            })
240            .collect();
241
242        let chunks: Vec<Vec<u8>> = contract_call_chunks(&calls, 2)
243            .map(|chunk| chunk.iter().map(|call| call.call_data[0]).collect())
244            .collect();
245
246        assert_eq!(chunks, vec![vec![0, 1], vec![2, 3], vec![4]]);
247    }
248
249    #[rstest]
250    fn contract_call_chunks_treats_zero_limit_as_one() {
251        let target = address!("25b76A90E389bD644a29db919b136Dc63B174Ec7");
252        let calls: Vec<ContractCall> = (0u8..3)
253            .map(|value| ContractCall {
254                target,
255                allow_failure: true,
256                call_data: vec![value],
257            })
258            .collect();
259
260        let chunks: Vec<Vec<u8>> = contract_call_chunks(&calls, 0)
261            .map(|chunk| chunk.iter().map(|call| call.call_data[0]).collect())
262            .collect();
263
264        assert_eq!(chunks, vec![vec![0], vec![1], vec![2]]);
265    }
266}
nautilus_blockchain/contracts/base.rs

nautilus_blockchain/contracts/
base.rs
