feat: jsonrpc batch requests (#653)

Author: xJonathanLEI

README.md

@@ -92,19 +92,21 @@ Examples can be found in the [examples folder](./examples):
 
 6. [Query the latest block number with JSON-RPC](./examples/jsonrpc.rs)
 
-7. [Call a contract view function](./examples/erc20_balance.rs)
+7. [Batched JSON-RPC requests](./examples/batch.rs)
 
-8. [Deploy an Argent X account to a pre-funded address](./examples/deploy_argent_account.rs)
+8. [Call a contract view function](./examples/erc20_balance.rs)
 
-9. [Inspect public key with Ledger](./examples/ledger_public_key.rs)
+9. [Deploy an Argent X account to a pre-funded address](./examples/deploy_argent_account.rs)
 
-10. [Deploy an OpenZeppelin account with Ledger](./examples/deploy_account_with_ledger.rs)
+10. [Inspect public key with Ledger](./examples/ledger_public_key.rs)
 
-11. [Transfer ERC20 tokens with Ledger](./examples/transfer_with_ledger.rs)
+11. [Deploy an OpenZeppelin account with Ledger](./examples/deploy_account_with_ledger.rs)
 
-12. [Parsing a JSON-RPC request on the server side](./examples/parse_jsonrpc_request.rs)
+12. [Transfer ERC20 tokens with Ledger](./examples/transfer_with_ledger.rs)
 
-13. [Inspecting a erased provider-specific error type](./examples/downcast_provider_error.rs)
+13. [Parsing a JSON-RPC request on the server side](./examples/parse_jsonrpc_request.rs)
+
+14. [Inspecting a erased provider-specific error type](./examples/downcast_provider_error.rs)
 
 ## License
 

examples/batch.rs

@@ -0,0 +1,36 @@
+use starknet::providers::{
+    jsonrpc::{HttpTransport, JsonRpcClient},
+    Provider, ProviderRequestData, ProviderResponseData, Url,
+};
+use starknet_core::types::{
+    requests::{BlockNumberRequest, GetBlockTransactionCountRequest},
+    BlockId,
+};
+
+#[tokio::main]
+async fn main() {
+    let provider = JsonRpcClient::new(HttpTransport::new(
+        Url::parse("https://starknet-sepolia.public.blastapi.io/rpc/v0_7").unwrap(),
+    ));
+
+    let responses = provider
+        .batch_requests([
+            ProviderRequestData::BlockNumber(BlockNumberRequest),
+            ProviderRequestData::GetBlockTransactionCount(GetBlockTransactionCountRequest {
+                block_id: BlockId::Number(100),
+            }),
+        ])
+        .await
+        .unwrap();
+
+    match (&responses[0], &responses[1]) {
+        (
+            ProviderResponseData::BlockNumber(block_number),
+            ProviderResponseData::GetBlockTransactionCount(count),
+        ) => {
+            println!("The latest block is #{}", block_number);
+            println!("Block #100 has {} transactions", count);
+        }
+        _ => panic!("unexpected response type"),
+    }
+}

examples/parse_jsonrpc_request.rs

@@ -1,4 +1,4 @@
-use starknet_providers::jsonrpc::{JsonRpcRequest, JsonRpcRequestData};
+use starknet_providers::{jsonrpc::JsonRpcRequest, ProviderRequestData};
 
 fn main() {
     // Let's pretend this is the raw request body coming from HTTP
@@ -17,7 +17,7 @@ fn main() {
     println!("Request received: {:#?}", parsed_request);
 
     match parsed_request.data {
-        JsonRpcRequestData::GetBlockTransactionCount(req) => {
+        ProviderRequestData::GetBlockTransactionCount(req) => {
             println!(
                 "starknet_getBlockTransactionCount request received for block: {:?}",
                 req.block_id

starknet-providers/src/any.rs

@@ -12,7 +12,7 @@ use starknet_core::types::{
 
 use crate::{
     jsonrpc::{HttpTransport, JsonRpcClient},
-    Provider, ProviderError, SequencerGatewayProvider,
+    Provider, ProviderError, ProviderRequestData, ProviderResponseData, SequencerGatewayProvider,
 };
 
 /// A convenient Box-able type that implements the [Provider] trait. This can be useful when you
@@ -665,4 +665,21 @@ impl Provider for AnyProvider {
             }
         }
     }
+
+    async fn batch_requests<R>(
+        &self,
+        requests: R,
+    ) -> Result<Vec<ProviderResponseData>, ProviderError>
+    where
+        R: AsRef<[ProviderRequestData]> + Send + Sync,
+    {
+        match self {
+            Self::JsonRpcHttp(inner) => {
+                <JsonRpcClient<HttpTransport> as Provider>::batch_requests(inner, requests).await
+            }
+            Self::SequencerGateway(inner) => {
+                <SequencerGatewayProvider as Provider>::batch_requests(inner, requests).await
+            }
+        }
+    }
 }