feat(katana-runner): allow configuring chain id

crates/katana/node-bindings/src/json.rs

@@ -69,3 +69,12 @@ pub struct AccountInfo {
 pub struct RpcAddr {
     pub addr: SocketAddr,
 }
+
+/// {
+///     "message": "Starting node.",
+///     "chain": "SN_SEPOLIA"
+/// }
+#[derive(Deserialize, Debug)]
+pub struct ChainId {
+    pub chain: String,
+}

crates/katana/node-bindings/src/lib.rs

@@ -14,8 +14,8 @@ use std::process::{Child, Command};
 use std::str::FromStr;
 use std::time::{Duration, Instant};
 
-use json::RpcAddr;
 use starknet::core::types::{Felt, FromStrError};
+use starknet::core::utils::cairo_short_string_to_felt;
 use starknet::macros::short_string;
 use starknet::signers::SigningKey;
 use thiserror::Error;
@@ -130,6 +130,10 @@ pub enum Error {
     #[error("missing rpc server address")]
     MissingSocketAddr,
 
+    /// A line indicating the instance address was found but the actual value was not.
+    #[error("missing chain id")]
+    MissingChainId,
+
     #[error("encountered unexpected format: {0}")]
     UnexpectedFormat(String),
 
@@ -142,6 +146,8 @@ pub enum Error {
 
 /// The string indicator from which the RPC server address can be extracted from.
 const RPC_ADDR_LOG_SUBSTR: &str = "RPC server started.";
+/// The string indicator from which the chain id can be extracted from.
+const CHAIN_ID_LOG_SUBSTR: &str = "Starting node.";
 
 /// Builder for launching `katana`.
 ///
@@ -494,10 +500,9 @@ impl Katana {
         let mut accounts = Vec::new();
         // var to store the current account being processed
         let mut current_account: Option<Account> = None;
-
-        // TODO: the chain id should be fetched from stdout as well but Katana doesn't display the
-        // chain id atm
-        let chain_id = self.chain_id.unwrap_or(short_string!("KATANA"));
+        // var to store the chain id parsed from the logs. default to KATANA (default katana chain
+        // id) if not specified
+        let mut chain_id: Felt = self.chain_id.unwrap_or(short_string!("KATANA"));
 
         loop {
             if start + Duration::from_millis(self.timeout.unwrap_or(KATANA_STARTUP_TIMEOUT_MILLIS))
@@ -514,13 +519,24 @@ impl Katana {
                 // Because we using a concrete type for rpc addr log, we need to parse this first.
                 // Otherwise if we were to inverse the if statements, the else block
                 // would never be executed as all logs can be parsed as `JsonLog`.
-                if let Ok(log) = serde_json::from_str::<JsonLog<RpcAddr>>(&line) {
+                if let Ok(log) = serde_json::from_str::<JsonLog<json::RpcAddr>>(&line) {
                     debug_assert!(log.fields.message.contains(RPC_ADDR_LOG_SUBSTR));
                     port = log.fields.other.addr.port();
                     // We can safely break here as we don't need any information after the rpc
                     // address
                     break;
                 }
+                // Try parsing as chain id log
+                else if let Ok(log) = serde_json::from_str::<JsonLog<json::ChainId>>(&line) {
+                    debug_assert!(log.fields.message.contains(CHAIN_ID_LOG_SUBSTR));
+                    let chain_raw = log.fields.other.chain;
+                    chain_id = if chain_raw.starts_with("0x") {
+                        Felt::from_str(&chain_raw)?
+                    } else {
+                        cairo_short_string_to_felt(&chain_raw)
+                            .map_err(|_| Error::UnexpectedFormat("invalid chain id".to_string()))?
+                    };
+                }
                 // Parse all logs as generic logs
                 else if let Ok(info) = serde_json::from_str::<JsonLog>(&line) {
                     // Check if this log is a katana startup info log
@@ -543,6 +559,10 @@ impl Katana {
                     break;
                 }
 
+                if line.contains(CHAIN_ID_LOG_SUBSTR) {
+                    chain_id = parse_chain_id_log(&line)?;
+                }
+
                 const ACC_ADDRESS_PREFIX: &str = "| Account address |";
                 if line.starts_with(ACC_ADDRESS_PREFIX) {
                     // If there is currently an account being handled, but we've reached the next
@@ -609,6 +629,23 @@ fn parse_rpc_addr_log(log: &str) -> Result<SocketAddr, Error> {
     Ok(SocketAddr::from_str(addr)?)
 }
 
+// Example chain ID log format (ansi color codes removed):
+// 2024-10-18T01:30:14.023880Z  INFO katana_node: Starting node. chain=0x4b4154414e41
+fn parse_chain_id_log(log: &str) -> Result<Felt, Error> {
+    // remove any ANSI escape codes from the log.
+    let cleaned = clean_ansi_escape_codes(log)?;
+
+    // This will separate the log into two parts as separated by `chain=` str and we take
+    // only the second part which is the chain ID.
+    let chain_part = cleaned.split("chain=").nth(1).ok_or(Error::MissingChainId)?.trim();
+    if chain_part.starts_with("0x") {
+        Ok(Felt::from_str(chain_part)?)
+    } else {
+        Ok(cairo_short_string_to_felt(chain_part)
+            .map_err(|_| Error::UnexpectedFormat("invalid chain id".to_string()))?)
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use starknet::providers::jsonrpc::HttpTransport;
@@ -634,10 +671,10 @@ mod tests {
 
     #[test]
     fn can_launch_katana_with_json_log() {
-        let katana = Katana::new().json_log(true).spawn();
+        let katana = Katana::new().json_log(true).chain_id(short_string!("SN_SEPOLIA")).spawn();
         // Assert default values when using JSON logging
         assert_eq!(katana.accounts().len(), 10);
-        assert_eq!(katana.chain_id(), short_string!("KATANA"));
+        assert_eq!(katana.chain_id(), short_string!("SN_SEPOLIA"));
         // assert that all accounts have private key
         assert!(katana.accounts().iter().all(|a| a.private_key.is_some()));
     }
@@ -705,4 +742,17 @@ mod tests {
         assert_eq!(addr.ip().to_string(), "127.0.0.1");
         assert_eq!(addr.port(), 60817);
     }
+
+    #[tokio::test]
+    async fn can_launch_katana_with_custom_chain_id() {
+        let custom_chain_id = Felt::from_str("0x1234").unwrap();
+        let katana = Katana::new().chain_id(custom_chain_id).spawn();
+
+        assert_eq!(katana.chain_id(), custom_chain_id);
+
+        let provider = JsonRpcClient::new(HttpTransport::new(katana.endpoint_url()));
+        let actual_chain_id = provider.chain_id().await.unwrap();
+
+        assert_eq!(custom_chain_id, actual_chain_id);
+    }
 }

crates/katana/node/src/lib.rs

@@ -96,6 +96,9 @@ impl Node {
     ///
     /// This method will start all the node process, running them until the node is stopped.
     pub async fn launch(self) -> Result<LaunchedNode> {
+        let chain = self.backend.chain_spec.id;
+        info!(%chain, "Starting node.");
+
         if let Some(ref cfg) = self.metrics_config {
             let addr = cfg.addr;
             let mut reports = Vec::new();

crates/katana/primitives/Cargo.toml

@@ -18,7 +18,6 @@ serde_json.workspace = true
 serde_with.workspace = true
 starknet.workspace = true
 starknet-crypto.workspace = true
-strum_macros.workspace = true
 thiserror.workspace = true
 
 alloy-primitives.workspace = true

crates/katana/primitives/src/chain.rs

@@ -4,7 +4,7 @@ use starknet::macros::short_string;
 use crate::{Felt, FromStrError};
 
 /// Known chain ids that has been assigned a name.
-#[derive(Debug, Clone, Copy, PartialEq, Eq, strum_macros::Display)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub enum NamedChainId {
     Mainnet,
@@ -44,6 +44,12 @@ impl NamedChainId {
     }
 }
 
+impl std::fmt::Display for NamedChainId {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.write_str(self.name())
+    }
+}
+
 /// This `struct` is created by the [`NamedChainId::try_from<u128>`] method.
 #[derive(Debug, thiserror::Error)]
 #[error("Unknown named chain id {0:#x}")]
@@ -185,9 +191,9 @@ mod tests {
         assert_eq!(ChainId::from(sepolia_id), ChainId::SEPOLIA);
         assert_eq!(ChainId::from(felt!("0x1337")), ChainId::Id(felt!("0x1337")));
 
-        assert_eq!(ChainId::MAINNET.to_string(), "Mainnet");
-        assert_eq!(ChainId::GOERLI.to_string(), "Goerli");
-        assert_eq!(ChainId::SEPOLIA.to_string(), "Sepolia");
+        assert_eq!(ChainId::MAINNET.to_string(), "SN_MAIN");
+        assert_eq!(ChainId::GOERLI.to_string(), "SN_GOERLI");
+        assert_eq!(ChainId::SEPOLIA.to_string(), "SN_SEPOLIA");
         assert_eq!(ChainId::Id(felt!("0x1337")).to_string(), "0x1337");
     }
 

crates/katana/runner/macro/src/config.rs

@@ -18,6 +18,7 @@
     pub db_dir: Option<syn::Expr>,
     pub block_time: Option<syn::Expr>,
     pub log_path: Option<syn::Expr>,
+    pub chain_id: Option<syn::Expr>,
 }
 
 impl Configuration {
@@ -32,6 +33,7 @@
             validation: None,
             block_time: None,
             crate_name: None,
+            chain_id: None,
         }
     }
 
@@ -105,6 +107,19 @@
         self.accounts = Some(accounts);
         Ok(())
     }
+
+    fn set_chain_id(
+        &mut self,
+        chain_id: syn::Expr,
+        span: proc_macro2::Span,
+    ) -> Result<(), syn::Error> {
+        if self.chain_id.is_some() {
+            return Err(syn::Error::new(span, "`chain_id` set multiple times."));
+        }
+
+        self.chain_id = Some(chain_id);
+        Ok(())
+    }
 }
 
 enum RunnerArg {
@@ -113,6 +128,7 @@
     Validation,
     Accounts,
     DbDir,
+    ChainId,
 }
 
 impl std::str::FromStr for RunnerArg {
@@ -125,9 +141,10 @@
             "validation" => Ok(RunnerArg::Validation),
             "accounts" => Ok(RunnerArg::Accounts),
             "db_dir" => Ok(RunnerArg::DbDir),
+            "chain_id" => Ok(RunnerArg::ChainId),
             _ => Err(format!(
                 "Unknown attribute {s} is specified; expected one of: `fee`, `validation`, \
-                 `accounts`, `db_dir`, `block_time`",
+                 `accounts`, `db_dir`, `block_time`, `chain_id`",
             )),
         }
     }
@@ -172,7 +189,9 @@
                     RunnerArg::DbDir => {
                         config.set_db_dir(expr.clone(), Spanned::span(&namevalue))?
                     }
-
+                    RunnerArg::ChainId => {
+                        config.set_chain_id(expr.clone(), Spanned::span(&namevalue))?
+                    }
                     RunnerArg::Fee => config.set_fee(expr.clone(), Spanned::span(&namevalue))?,
                 }
             }

crates/katana/runner/macro/src/entry.rs

@@ -74,7 +74,11 @@
     }
 
     if let Some(value) = config.log_path {
-        cfg = quote_spanned! (last_stmt_start_span=> #cfg, log_path: Some(#value), );
+        cfg = quote_spanned! (last_stmt_start_span=> #cfg log_path: Some(#value), );
+    }
+
+    if let Some(value) = config.chain_id {
+        cfg = quote_spanned! (last_stmt_start_span=> #cfg chain_id: Some(#value), );
     }
 
     if config.dev {

crates/katana/runner/src/lib.rs

@@ -67,6 +67,8 @@ pub struct KatanaRunnerConfig {
     pub db_dir: Option<PathBuf>,
     /// Whether to run the katana runner with the `dev` rpc endpoints.
     pub dev: bool,
+    /// The chain id to use.
+    pub chain_id: Option<Felt>,
 }
 
 impl Default for KatanaRunnerConfig {
@@ -82,6 +84,7 @@ impl Default for KatanaRunnerConfig {
             messaging: None,
             db_dir: None,
             dev: false,
+            chain_id: None,
         }
     }
 }
@@ -123,6 +126,10 @@ impl KatanaRunner {
             .dev(config.dev)
             .fee(!config.disable_fee);
 
+        if let Some(id) = config.chain_id {
+            builder = builder.chain_id(id);
+        }
+
         if let Some(block_time_ms) = config.block_time {
             builder = builder.block_time(block_time_ms);
         }

crates/katana/runner/tests/runner.rs

@@ -1,11 +1,20 @@
 use katana_runner::RunnerCtx;
+use starknet::macros::short_string;
 use starknet::providers::Provider;
 
 #[katana_runner::test(fee = false, accounts = 7)]
 fn simple(runner: &RunnerCtx) {
     assert_eq!(runner.accounts().len(), 7);
 }
 
+#[tokio::test(flavor = "multi_thread")]
+#[katana_runner::test(chain_id = short_string!("SN_SEPOLIA"))]
+async fn custom_chain_id(runner: &RunnerCtx) {
+    let provider = runner.provider();
+    let id = provider.chain_id().await.unwrap();
+    assert_eq!(id, short_string!("SN_SEPOLIA"));
+}
+
 #[katana_runner::test]
 fn with_return(_: &RunnerCtx) -> Result<(), Box<dyn std::error::Error>> {
     Ok(())
@@ -15,6 +24,7 @@ fn with_return(_: &RunnerCtx) -> Result<(), Box<dyn std::error::Error>> {
 #[katana_runner::test]
 async fn with_async(ctx: &RunnerCtx) -> Result<(), Box<dyn std::error::Error>> {
     let provider = ctx.provider();
-    let _ = provider.chain_id().await?;
+    let id = provider.chain_id().await?;
+    assert_eq!(id, short_string!("KATANA"));
     Ok(())
 }