mapping

Cargo.toml

@@ -39,7 +39,7 @@ tracing = "0.1.37"
 tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }
 tree_hash = "0.6.0"
 tree_hash_derive = "0.6.0"
-url = "2.5.0"
+url = { version="2.5.0", features=["serde"] }
 
 
 [dev-dependencies]

README.md

@@ -40,15 +40,23 @@ To execute the forward service, use the following command:
 Example `configuration.toml`:
 
 ```toml
-beacon-urls = ["beacon-url-1", "beacon-url-2"]
+beacon-nodes = ["beacon-url-1", "beacon-url-2"]
 
-[[lookahead-providers-relays]]
+[[lookahead]]
 chain-id = 1
-relay-urls = ["relay-1", "relay-2"]
+relays = ["relay-1", "relay-2"]
 
-[[lookahead-providers-relays]]
+[[lookahead]]
+url-provider = "lookahead"
 chain-id = 2
-relay-urls = ["relay-3"]
+relays = ["relay-3"]
+[[lookahead.registry]]
+"0x8248efd1f054fcccd090879c4011ed91ee9f9d0db5ad125ae1af74fdd33de809ddc882400d99b5184ca065d4570df8cc"  = "http://a-preconfer-url.xyz"
 ```
 
+### Details
+- url-provider: Specifies the source of the URL. It can be either lookahead or url-mapping. 
+  - If set to **lookahead**, the URL is derived from the lookahead entry. 
+  - If set to **url-mapping**, the URL is determined by looking up the public keys between the lookahead entry public key and the map provided in registry.
+
 Make sure to provide the necessary beacon and relay URLs in the configuration file.

config.example.toml

@@ -1,5 +1,8 @@
-beacon-urls = ["https:://beacon-url"]
+beacon-nodes = ["https:://beacon-url"]
 
-[[lookahead-providers-relays]]
+[[lookahead]]
+url-provider = "lookahead"
 chain-id = 1
-relay-urls = ["https://relay-url"]
+relays = []
+[[lookahead.registry]]
+"0x8248efd1f054fcccd090879c4011ed91ee9f9d0db5ad125ae1af74fdd33de809ddc882400d99b5184ca065d4570df8cc"  = "http://a-preconfer-url.xyz"

src/config.rs

@@ -1,22 +1,63 @@
 use std::{fs, path::Path};
 
+use alloy::rpc::types::beacon::BlsPublicKey;
 use eyre::{Result, WrapErr};
-use serde::Deserialize;
+use hashbrown::HashMap;
+use serde::{Deserialize, Deserializer};
+use url::Url;
 
 #[derive(Debug, Deserialize)]
-pub struct Config {
-    #[serde(rename = "lookahead-providers-relays")]
-    pub lookahead_providers_relays: Vec<LookaheadProvider>,
-    #[serde(rename = "beacon-urls")]
-    pub beacon_urls: Vec<String>,
+#[serde(rename_all = "kebab-case")]
+pub enum Provider {
+    Lookahead,
+    Registry,
 }
 
 #[derive(Debug, Deserialize)]
-pub struct LookaheadProvider {
-    #[serde(rename = "chain-id")]
+pub struct Config {
+    #[serde(rename = "lookahead")]
+    pub lookaheads: Vec<Lookahead>,
+    #[serde(rename = "beacon-nodes")]
+    pub beacon_nodes: Vec<String>,
+}
+
+#[derive(Debug)]
+pub struct Lookahead {
     pub chain_id: u16,
-    #[serde(rename = "relay-urls")]
-    pub relay_urls: Vec<String>,
+    pub relays: Vec<String>,
+    pub registry: Option<HashMap<BlsPublicKey, Url>>,
+    pub provider: Provider,
+}
+
+impl<'de> Deserialize<'de> for Lookahead {
+    fn deserialize<D>(deserializer: D) -> Result<Lookahead, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        #[derive(Deserialize)]
+        #[serde(rename_all = "kebab-case")]
+        struct LookaheadHelper {
+            chain_id: u16,
+            relays: Vec<String>,
+            registry: Option<HashMap<BlsPublicKey, Url>>,
+            url_provider: Provider,
+        }
+
+        let helper = LookaheadHelper::deserialize(deserializer)?;
+
+        if matches!(helper.url_provider, Provider::Registry) && helper.registry.is_none() {
+            return Err(serde::de::Error::custom(
+                "registry map is mandatory when url-provider is set to registry",
+            ));
+        }
+
+        Ok(Lookahead {
+            chain_id: helper.chain_id,
+            relays: helper.relays,
+            registry: helper.registry,
+            provider: helper.url_provider,
+        })
+    }
 }
 
 impl Config {
@@ -25,3 +66,83 @@ impl Config {
         toml::from_str(&toml_str).wrap_err("could not parse configuration file")
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use std::str::FromStr;
+
+    use super::*;
+
+    #[test]
+    fn test_deserialize_config() {
+        let data = r#"
+        beacon-nodes = ["node1", "node2"]
+        [[lookahead]]
+        chain-id = 1
+        url-provider = "lookahead"
+        relays = ["relay1", "relay2"]
+        [lookahead.registry]
+        "0x8248efd1f054fcccd090879c4011ed91ee9f9d0db5ad125ae1af74fdd33de809ddc882400d99b5184ca065d4570df8cc" = "localhost:21009"
+        "#;
+
+        let expected_registry = {
+            let mut registry = HashMap::new();
+            registry.insert(BlsPublicKey::from_str("0x8248efd1f054fcccd090879c4011ed91ee9f9d0db5ad125ae1af74fdd33de809ddc882400d99b5184ca065d4570df8cc").unwrap(), Url::from_str("localhost:21009").unwrap());
+            registry
+        };
+
+        let expected_lookahead = Lookahead {
+            chain_id: 1,
+            relays: vec!["relay1".to_string(), "relay2".to_string()],
+            registry: Some(expected_registry),
+            provider: Provider::Lookahead,
+        };
+
+        let _expected_config = Config {
+            lookaheads: vec![expected_lookahead],
+            beacon_nodes: vec!["node1".to_string(), "node2".to_string()],
+        };
+
+        let config: Config = toml::from_str(data).unwrap();
+        assert!(matches!(config, _expected_config));
+    }
+
+    #[test]
+    fn test_deserialize_config_no_lookahead_registry() {
+        let data = r#"
+        beacon-nodes = ["node1", "node2"]
+        [[lookahead]]
+        chain-id = 1
+        url-provider = "lookahead"
+        relays = ["relay1", "relay2"]
+        "#;
+
+        let expected_lookahead = Lookahead {
+            chain_id: 1,
+            relays: vec!["relay1".to_string(), "relay2".to_string()],
+            registry: None,
+            provider: Provider::Lookahead,
+        };
+
+        let _expected_config = Config {
+            lookaheads: vec![expected_lookahead],
+            beacon_nodes: vec!["node1".to_string(), "node2".to_string()],
+        };
+
+        let config: Config = toml::from_str(data).unwrap();
+        assert!(matches!(config, _expected_config));
+    }
+
+    #[test]
+    fn test_fail_if_wrong_registry_combination() {
+        let data = r#"
+        beacon-nodes = ["node1", "node2"]
+        [[lookahead]]
+        chain-id = 1
+        url-provider = "registry"
+        relays = ["relay1", "relay2"]
+        "#;
+        let config: Result<Config> = toml::from_str(data).wrap_err("error parsing config");
+        assert!(config.is_err());
+    }
+}