fix: dynamic chain support

Cargo.toml

@@ -7,10 +7,7 @@ authors = ["WalletConnect Team"]
 license = "Apache-2.0"
 
 [workspace]
-members = [
-    "relay_client",
-    "relay_rpc"
-]
+members = ["blockchain_api", "relay_client", "relay_rpc"]
 
 [features]
 default = ["full"]
@@ -35,12 +32,12 @@ once_cell = "1.19"
 
 [[example]]
 name = "websocket_client"
-required-features = ["client","rpc"]
+required-features = ["client", "rpc"]
 
 [[example]]
 name = "http_client"
-required-features = ["client","rpc"]
+required-features = ["client", "rpc"]
 
 [[example]]
 name = "webhook"
-required-features = ["client","rpc"]
+required-features = ["client", "rpc"]

blockchain_api/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "blockchain_api"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+once_cell = "1.16"
+relay_rpc = { path = "../relay_rpc" }
+reqwest = "0.11"
+serde = "1.0"
+tokio = { version = "1.0", features = ["test-util", "macros"] }
+tracing = "0.1.40"
+url = "2"

blockchain_api/src/lib.rs

@@ -0,0 +1,133 @@
+pub use reqwest::Error;
+use {
+    relay_rpc::{auth::cacao::signature::eip1271::get_rpc_url::GetRpcUrl, domain::ProjectId},
+    serde::Deserialize,
+    std::{collections::HashSet, convert::Infallible, sync::Arc, time::Duration},
+    tokio::{sync::RwLock, task::JoinHandle},
+    tracing::error,
+    url::Url,
+};
+
+const BLOCKCHAIN_API_SUPPORTED_CHAINS_ENDPOINT_STR: &str = "/v1/supported-chains";
+const BLOCKCHAIN_API_RPC_ENDPOINT_STR: &str = "/v1";
+const BLOCKCHAIN_API_RPC_CHAIN_ID_PARAM: &str = "chainId";
+const BLOCKCHAIN_API_RPC_PROJECT_ID_PARAM: &str = "projectId";
+
+const SUPPORTED_CHAINS_REFRESH_INTERVAL: Duration = Duration::from_secs(60 * 60 * 4);
+
+#[derive(Debug, Deserialize)]
+struct SupportedChainsResponse {
+    pub http: HashSet<String>,
+}
+
+#[derive(Debug, Clone)]
+pub struct BlockchainApiProvider {
+    project_id: ProjectId,
+    blockchain_api_rpc_endpoint: Url,
+    supported_chains: Arc<RwLock<HashSet<String>>>,
+    refresh_job: Arc<JoinHandle<Infallible>>,
+}
+
+impl Drop for BlockchainApiProvider {
+    fn drop(&mut self) {
+        self.refresh_job.abort();
+    }
+}
+
+async fn refresh_supported_chains(
+    blockchain_api_supported_chains_endpoint: Url,
+    supported_chains: &RwLock<HashSet<String>>,
+) -> Result<(), Error> {
+    let response = reqwest::get(blockchain_api_supported_chains_endpoint)
+        .await?
+        .json::<SupportedChainsResponse>()
+        .await?;
+    *supported_chains.write().await = response.http;
+    Ok(())
+}
+
+impl BlockchainApiProvider {
+    pub async fn new(project_id: ProjectId, blockchain_api_endpoint: Url) -> Result<Self, Error> {
+        let blockchain_api_rpc_endpoint = blockchain_api_endpoint
+            .join(BLOCKCHAIN_API_RPC_ENDPOINT_STR)
+            .expect("Safe unwrap: hardcoded URL: BLOCKCHAIN_API_RPC_ENDPOINT_STR");
+        let blockchain_api_supported_chains_endpoint = blockchain_api_endpoint
+            .join(BLOCKCHAIN_API_SUPPORTED_CHAINS_ENDPOINT_STR)
+            .expect("Safe unwrap: hardcoded URL: BLOCKCHAIN_API_SUPPORTED_CHAINS_ENDPOINT_STR");
+
+        let supported_chains = Arc::new(RwLock::new(HashSet::new()));
+        refresh_supported_chains(
+            blockchain_api_supported_chains_endpoint.clone(),
+            &supported_chains,
+        )
+        .await?;
+        let mut interval = tokio::time::interval(SUPPORTED_CHAINS_REFRESH_INTERVAL);
+        interval.tick().await;
+        let refresh_job = tokio::task::spawn({
+            let supported_chains = supported_chains.clone();
+            let blockchain_api_supported_chains_endpoint =
+                blockchain_api_supported_chains_endpoint.clone();
+            async move {
+                loop {
+                    interval.tick().await;
+                    if let Err(e) = refresh_supported_chains(
+                        blockchain_api_supported_chains_endpoint.clone(),
+                        &supported_chains,
+                    )
+                    .await
+                    {
+                        error!("Failed to refresh supported chains: {e}");
+                    }
+                }
+            }
+        });
+        Ok(Self {
+            project_id,
+            blockchain_api_rpc_endpoint,
+            supported_chains,
+            refresh_job: Arc::new(refresh_job),
+        })
+    }
+}
+
+fn build_rpc_url(blockchain_api_rpc_endpoint: Url, chain_id: &str, project_id: &str) -> Url {
+    let mut url = blockchain_api_rpc_endpoint;
+    url.query_pairs_mut()
+        .append_pair(BLOCKCHAIN_API_RPC_CHAIN_ID_PARAM, chain_id)
+        .append_pair(BLOCKCHAIN_API_RPC_PROJECT_ID_PARAM, project_id);
+    url
+}
+
+impl GetRpcUrl for BlockchainApiProvider {
+    async fn get_rpc_url(&self, chain_id: String) -> Option<Url> {
+        self.supported_chains
+            .read()
+            .await
+            .contains(&chain_id)
+            .then(|| {
+                build_rpc_url(
+                    self.blockchain_api_rpc_endpoint.clone(),
+                    &chain_id,
+                    self.project_id.as_ref(),
+                )
+            })
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[tokio::test]
+    async fn rpc_endpoint() {
+        assert_eq!(
+            build_rpc_url(
+                "https://rpc.walletconnect.com/v1".parse().unwrap(),
+                "eip155:1",
+                "my-project-id"
+            )
+            .as_str(),
+            "https://rpc.walletconnect.com/v1?chainId=eip155%3A1&projectId=my-project-id"
+        );
+    }
+}

relay_rpc/src/auth/cacao.rs

@@ -32,6 +32,9 @@ pub enum CacaoError {
     #[error("Invalid address")]
     AddressInvalid,
 
+    #[error("EIP-1271 signatures not supported")]
+    Eip1271NotSupported,
+
     #[error("Unsupported signature type")]
     UnsupportedSignature,
 
@@ -94,7 +97,7 @@ pub struct Cacao {
 impl Cacao {
     const ETHEREUM: &'static str = "Ethereum";
 
-    pub async fn verify(&self, provider: &impl GetRpcUrl) -> Result<bool, CacaoError> {
+    pub async fn verify(&self, provider: Option<&impl GetRpcUrl>) -> Result<bool, CacaoError> {
         self.p.validate()?;
         self.h.validate()?;
         self.s.verify(self, provider).await

relay_rpc/src/auth/cacao/signature/eip1271/get_rpc_url.rs

@@ -1,5 +1,6 @@
 use url::Url;
 
 pub trait GetRpcUrl {
-    fn get_rpc_url(&self, chain_id: String) -> Option<Url>;
+    #[allow(async_fn_in_trait)]
+    async fn get_rpc_url(&self, chain_id: String) -> Option<Url>;
 }

relay_rpc/src/auth/cacao/signature/eip1271/mod.rs

@@ -8,7 +8,6 @@ use {
     url::Url,
 };
 
-pub mod blockchain_api;
 pub mod get_rpc_url;
 
 pub const EIP1271: &str = "eip1271";

relay_rpc/src/auth/cacao/signature/mod.rs

@@ -23,7 +23,7 @@ impl Signature {
     pub async fn verify(
         &self,
         cacao: &Cacao,
-        get_provider: &impl GetRpcUrl,
+        provider: Option<&impl GetRpcUrl>,
     ) -> Result<bool, CacaoError> {
         let address = cacao.p.address()?;
 
@@ -36,20 +36,24 @@ impl Signature {
         match self.t.as_str() {
             EIP191 => verify_eip191(&signature, &address, hash),
             EIP1271 => {
-                let chain_id = cacao.p.chain_id_reference()?;
-                let provider = get_provider.get_rpc_url(chain_id);
                 if let Some(provider) = provider {
-                    verify_eip1271(
-                        signature,
-                        Address::from_str(&address).map_err(|_| CacaoError::AddressInvalid)?,
-                        &hash.finalize()[..]
-                            .try_into()
-                            .expect("hash length is 32 bytes"),
-                        provider,
-                    )
-                    .await
+                    let chain_id = cacao.p.chain_id_reference()?;
+                    let provider = provider.get_rpc_url(chain_id).await;
+                    if let Some(provider) = provider {
+                        verify_eip1271(
+                            signature,
+                            Address::from_str(&address).map_err(|_| CacaoError::AddressInvalid)?,
+                            &hash.finalize()[..]
+                                .try_into()
+                                .expect("hash length is 32 bytes"),
+                            provider,
+                        )
+                        .await
+                    } else {
+                        Err(CacaoError::ProviderNotAvailable)
+                    }
                 } else {
-                    Err(CacaoError::ProviderNotAvailable)
+                    Err(CacaoError::Eip1271NotSupported)
                 }
             }
             _ => Err(CacaoError::UnsupportedSignature),

relay_rpc/src/auth/cacao/tests.rs

@@ -3,7 +3,7 @@ use {super::signature::eip1271::get_rpc_url::GetRpcUrl, crate::auth::cacao::Caca
 struct MockGetRpcUrl;
 
 impl GetRpcUrl for MockGetRpcUrl {
-    fn get_rpc_url(&self, _: String) -> Option<Url> {
+    async fn get_rpc_url(&self, _: String) -> Option<Url> {
         None
     }
 }