Add ChainSource enum

.. which will allow us to switch between different chain sources.

Author: tnull

src/builder.rs

@@ -5,10 +5,9 @@
 // http://opensource.org/licenses/MIT>, at your option. You may not use this file except in
 // accordance with one or both of these licenses.
 
-use crate::config::{
-	default_user_config, Config, DEFAULT_ESPLORA_CLIENT_TIMEOUT_SECS, DEFAULT_ESPLORA_SERVER_URL,
-	WALLET_KEYS_SEED_LEN,
-};
+use crate::chain::{DEFAULT_ESPLORA_CLIENT_TIMEOUT_SECS, DEFAULT_ESPLORA_SERVER_URL};
+use crate::config::{default_user_config, Config, WALLET_KEYS_SEED_LEN};
+
 use crate::connection::ConnectionManager;
 use crate::event::EventQueue;
 use crate::fee_estimator::OnchainFeeEstimator;

src/chain/mod.rs

@@ -0,0 +1,37 @@
+// This file is Copyright its original authors, visible in version control history.
+//
+// This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
+// http://opensource.org/licenses/MIT>, at your option. You may not use this file except in
+// accordance with one or both of these licenses.
+
+use crate::logger::FilesystemLogger;
+
+use esplora_client::AsyncClient as EsploraAsyncClient;
+
+use std::sync::Arc;
+
+// The default Esplora server we're using.
+pub(crate) const DEFAULT_ESPLORA_SERVER_URL: &str = "https://blockstream.info/api";
+
+// The default Esplora client timeout we're using.
+pub(crate) const DEFAULT_ESPLORA_CLIENT_TIMEOUT_SECS: u64 = 10;
+
+pub(crate) enum ChainSource {
+	Esplora {
+		esplora_client: EsploraAsyncClient,
+		logger: Arc<FilesystemLogger>,
+	},
+}
+
+impl ChainSource {
+	pub(crate) fn new_esplora(
+		server_url: String,
+		logger: Arc<FilesystemLogger>,
+	) -> Self {
+		let mut client_builder = esplora_client::Builder::new(&server_url.clone());
+		client_builder = client_builder.timeout(DEFAULT_ESPLORA_CLIENT_TIMEOUT_SECS);
+		let esplora_client = client_builder.build_async().unwrap();
+		Self::Esplora { esplora_client, logger }
+	}
+}

src/config.rs

@@ -34,12 +34,6 @@ pub(crate) const BDK_CLIENT_STOP_GAP: usize = 20;
 // The number of concurrent requests made against the API provider.
 pub(crate) const BDK_CLIENT_CONCURRENCY: usize = 4;
 
-// The default Esplora server we're using.
-pub(crate) const DEFAULT_ESPLORA_SERVER_URL: &str = "https://blockstream.info/api";
-
-// The default Esplora client timeout we're using.
-pub(crate) const DEFAULT_ESPLORA_CLIENT_TIMEOUT_SECS: u64 = 10;
-
 // The timeout after which we abandon retrying failed payments.
 pub(crate) const LDK_PAYMENT_RETRY_TIMEOUT: Duration = Duration::from_secs(10);
 

src/lib.rs

@@ -74,6 +74,7 @@
 
 mod balance;
 mod builder;
+mod chain;
 mod config;
 mod connection;
 mod error;