eth_subscribe RPC method returns 16-character subscription ID instead of 32-byte ID

[krisbitney]

Description

Recently, there was a change to the behavior of eth_subscribe. It is now returning a 16-character subscription ID (e.g. TlCPBeW4fku7BlSo) instead of a 32-byte ID.

I believe the changes in this PR may be related: #1504

Steps to Reproduce

        const result = (await client.transport.request({
          method: "eth_subscribe",
          params: ["newHeads"],
        })) as any

Expected vs. Actual Behavior

The expected behavior would be to receive a 32-byte hex string representing the subscription ID. The actual received value is a 16-character string, which presumably is a UTF-8 encoded representation of the 32-byte ID.

Environment

TypeScript with Viem

[conr2d]

On which binary is this issue found? With the Frontier template node, a 32-character hex string ID is returned as expected. If this issue occurs with your node implementation, please check whether this change has been properly applied to your code.

	// For Ethereum-compatible RPC.
-	config.rpc_id_provider = Some(Box::new(fc_rpc::EthereumSubIdProvider));
+	config.rpc.id_provider = Some(Box::new(fc_rpc::EthereumSubIdProvider));

	/* ... */

	let _rpc_handlers = sc_service::spawn_tasks(sc_service::SpawnTasksParams {
		config,
		client: client.clone(),
		backend: backend.clone(),
		task_manager: &mut task_manager,
		keystore: keystore_container.keystore(),
		transaction_pool: transaction_pool.clone(),
	});