From: Matt Corallo <git@bluematt.me>
Date: Tue, 4 May 2021 17:10:18 +0000 (+0000)
Subject: Make an initial dummy RPC call to check that the connection works
X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=a7a3f78356c28b252744f2a2743b0266686b4d4d;p=ldk-sample

Make an initial dummy RPC call to check that the connection works

This provides a much better panic message if the RPC password is
incorrect.
---

diff --git a/src/bitcoind_client.rs b/src/bitcoind_client.rs
index 58510ae..6d29ca0 100644
--- a/src/bitcoind_client.rs
+++ b/src/bitcoind_client.rs
@@ -67,7 +67,10 @@ impl BitcoindClient {
 		let http_endpoint = HttpEndpoint::for_host(host.clone()).with_port(port);
 		let rpc_credentials =
 			base64::encode(format!("{}:{}", rpc_user.clone(), rpc_password.clone()));
-		let bitcoind_rpc_client = RpcClient::new(&rpc_credentials, http_endpoint)?;
+		let mut bitcoind_rpc_client = RpcClient::new(&rpc_credentials, http_endpoint)?;
+		let _dummy = bitcoind_rpc_client.call_method::<BlockchainInfo>("getblockchaininfo", &vec![]).await
+			.map_err(|_| std::io::Error::new(std::io::ErrorKind::PermissionDenied,
+				"Failed to make initial call to bitcoind - please check your RPC user/password and access settings"))?;
 		let mut fees: HashMap<Target, AtomicU32> = HashMap::new();
 		fees.insert(Target::Background, AtomicU32::new(253));
 		fees.insert(Target::Normal, AtomicU32::new(2000));