coinbase bugfix from flashbots#215

Author: mralj

crates/rbuilder/src/backtest/backtest_build_block.rs

@@ -8,6 +8,9 @@
 use ahash::HashMap;
 use alloy_primitives::utils::format_ether;
 use alloy_rpc_client::RpcClient;
+use rand::rngs::OsRng;
+use revm_primitives::hex;
+use secp256k1::SecretKey;
 use url::Url;
 
 use crate::{
@@ -26,7 +29,7 @@ use crate::{
     utils::timestamp_as_u64,
 };
 use clap::Parser;
-use std::path::PathBuf;
+use std::{env, path::PathBuf};
 
 #[derive(Parser, Debug)]
 struct Cli {
@@ -106,6 +109,10 @@ where
         print_onchain_block_data(tx_sim_results, &orders, &block_data);
     }
 
+    if let Err(_) = config.base_config().coinbase_signer() {
+        add_env_coinbase_signer();
+    }
+
     let BacktestBlockInput {
         ctx, sim_orders, ..
     } = backtest_prepare_ctx_for_block(
@@ -406,3 +413,17 @@ fn print_onchain_block_data(
         }
     }
 }
+
+// Generate a random private key
+fn generate_private_key() -> String {
+    let mut rng = OsRng;
+    let secret_key = SecretKey::new(&mut rng);
+    let hex_secret_key = hex::encode(secret_key.secret_bytes());
+    hex_secret_key
+}
+
+// Add COINBASE_SECRET_KEY as an environment variable during runtime
+fn add_env_coinbase_signer() {
+    let private_key = generate_private_key();
+    env::set_var("COINBASE_SECRET_KEY", private_key);
+}

crates/rbuilder/src/live_builder/base_config.rs

@@ -12,13 +12,15 @@ use alloy_primitives::{Address, B256};
 use eyre::{eyre, Context};
 use jsonrpsee::RpcModule;
 use lazy_static::lazy_static;
+use rand::rngs::OsRng;
 use reth::chainspec::chain_value_parser;
 use reth_chainspec::ChainSpec;
 use reth_db::DatabaseEnv;
 use reth_node_api::NodeTypesWithDBAdapter;
 use reth_node_ethereum::EthereumNode;
 use reth_primitives::StaticFileSegment;
 use reth_provider::{HeaderProvider, StateProviderFactory, StaticFileProviderFactory};
+use secp256k1::SecretKey;
 use serde::{Deserialize, Deserializer};
 use serde_with::{serde_as, DeserializeAs};
 use sqlx::PgPool;