example_block_traces/
main.rs

1//! Example that show how to replay a block and trace the execution of each transaction.
2//!
3//! The EIP3155 trace of each transaction is saved into file `traces/{tx_number}.json`.
4#![cfg_attr(not(test), warn(unused_crate_dependencies))]
5
6use alloy_consensus::Transaction;
7use alloy_eips::{BlockId, BlockNumberOrTag};
8use alloy_provider::{network::primitives::BlockTransactions, Provider, ProviderBuilder};
9use indicatif::ProgressBar;
10use revm::{
11    context::TxEnv,
12    database::{AlloyDB, CacheDB, StateBuilder},
13    database_interface::WrapDatabaseAsync,
14    inspector::{inspectors::TracerEip3155, InspectEvm},
15    primitives::{TxKind, U256},
16    Context, MainBuilder, MainContext,
17};
18use std::fs::create_dir_all;
19use std::fs::OpenOptions;
20use std::io::BufWriter;
21use std::io::Write;
22use std::sync::Arc;
23use std::sync::Mutex;
24use std::time::Instant;
25
26struct FlushWriter {
27    writer: Arc<Mutex<BufWriter<std::fs::File>>>,
28}
29
30impl FlushWriter {
31    fn new(writer: Arc<Mutex<BufWriter<std::fs::File>>>) -> Self {
32        Self { writer }
33    }
34}
35
36impl Write for FlushWriter {
37    fn write(&mut self, buf: &[u8]) -> std::io::Result<usize> {
38        self.writer.lock().unwrap().write(buf)
39    }
40
41    fn flush(&mut self) -> std::io::Result<()> {
42        self.writer.lock().unwrap().flush()
43    }
44}
45
46#[tokio::main]
47async fn main() -> anyhow::Result<()> {
48    create_dir_all("traces")?;
49
50    // Set up the HTTP transport which is consumed by the RPC client.
51    let rpc_url = "https://mainnet.infura.io/v3/c60b0bb42f8a4c6481ecd229eddaca27".parse()?;
52
53    // Create a provider
54    let client = ProviderBuilder::new().connect_http(rpc_url);
55
56    // Params
57    let chain_id: u64 = 1;
58    let block_number = 10889447;
59
60    // Fetch the transaction-rich block
61    let block = match client
62        .get_block_by_number(BlockNumberOrTag::Number(block_number))
63        .full()
64        .await
65    {
66        Ok(Some(block)) => block,
67        Ok(None) => anyhow::bail!("Block not found"),
68        Err(error) => anyhow::bail!("Error: {:?}", error),
69    };
70    println!("Fetched block number: {}", block.header.number);
71    let previous_block_number = block_number - 1;
72
73    // Use the previous block state as the db with caching
74    let prev_id: BlockId = previous_block_number.into();
75    // SAFETY: This cannot fail since this is in the top-level tokio runtime
76
77    let state_db = WrapDatabaseAsync::new(AlloyDB::new(client, prev_id)).unwrap();
78    let cache_db: CacheDB<_> = CacheDB::new(state_db);
79    let mut state = StateBuilder::new_with_database(cache_db).build();
80    let ctx = Context::mainnet()
81        .with_db(&mut state)
82        .modify_block_chained(|b| {
83            b.number = U256::from(block.header.number);
84            b.beneficiary = block.header.beneficiary;
85            b.timestamp = U256::from(block.header.timestamp);
86
87            b.difficulty = block.header.difficulty;
88            b.gas_limit = block.header.gas_limit;
89            b.basefee = block.header.base_fee_per_gas.unwrap_or_default();
90        })
91        .modify_cfg_chained(|c| {
92            c.chain_id = chain_id;
93        });
94
95    let write = OpenOptions::new()
96        .write(true)
97        .create(true)
98        .truncate(true)
99        .open("traces/0.json");
100    let inner = Arc::new(Mutex::new(BufWriter::new(
101        write.expect("Failed to open file"),
102    )));
103    let writer = FlushWriter::new(Arc::clone(&inner));
104    let mut evm = ctx.build_mainnet_with_inspector(TracerEip3155::new(Box::new(writer)));
105
106    let txs = block.transactions.len();
107    println!("Found {txs} transactions.");
108
109    let console_bar = Arc::new(ProgressBar::new(txs as u64));
110    let start = Instant::now();
111
112    // Create the traces directory if it doesn't exist
113    std::fs::create_dir_all("traces").expect("Failed to create traces directory");
114
115    // Fill in CfgEnv
116    let BlockTransactions::Full(transactions) = block.transactions else {
117        panic!("Wrong transaction type")
118    };
119
120    for tx in transactions {
121        // Construct the file writer to write the trace to
122        let tx_number = tx.transaction_index.unwrap_or_default();
123
124        let tx = TxEnv::builder()
125            .caller(tx.inner.signer())
126            .gas_limit(tx.gas_limit())
127            .gas_price(tx.gas_price().unwrap_or(tx.inner.max_fee_per_gas()))
128            .value(tx.value())
129            .data(tx.input().to_owned())
130            .gas_priority_fee(tx.max_priority_fee_per_gas())
131            .chain_id(Some(chain_id))
132            .nonce(tx.nonce())
133            .access_list(tx.access_list().cloned().unwrap_or_default())
134            .kind(match tx.to() {
135                Some(to_address) => TxKind::Call(to_address),
136                None => TxKind::Create,
137            })
138            .build()
139            .unwrap();
140
141        let file_name = format!("traces/{tx_number}.json");
142        let write = OpenOptions::new()
143            .write(true)
144            .create(true)
145            .truncate(true)
146            .open(file_name);
147        let inner = Arc::new(Mutex::new(BufWriter::new(
148            write.expect("Failed to open file"),
149        )));
150        let writer = FlushWriter::new(Arc::clone(&inner));
151
152        // Inspect and commit the transaction to the EVM
153        let res: Result<_, _> = evm.inspect_one(tx, TracerEip3155::new(Box::new(writer)));
154
155        if let Err(error) = res {
156            println!("Got error: {error:?}");
157        }
158
159        // Flush the file writer
160        inner.lock().unwrap().flush().expect("Failed to flush file");
161
162        console_bar.inc(1);
163    }
164
165    console_bar.finish_with_message("Finished all transactions.");
166
167    let elapsed = start.elapsed();
168    println!(
169        "Finished execution. Total CPU time: {:.6}s",
170        elapsed.as_secs_f64()
171    );
172
173    Ok(())
174}
example_block_traces/main.rs

example_block_traces/
main.rs
