fix: retry mechanism (MetaMask#77)

Author: darioAnongba

Cargo.lock

@@ -34,11 +34,12 @@ wasm-bindgen-futures = { version = "0.4.50", optional = true }
 anyhow = { version = "1.0.98", default-features = false }
 serde = { version = "1.0.219", default-features = false, features = ["derive"] }
 serde-wasm-bindgen = "0.6.5"
-web-sys = { version = "0.3.77", default-features = false }
+web-sys = { version = "0.3.77", default-features = false, features = [
+    "Window",
+] }
 
 # Compatibility to compile to WASM
 getrandom = { version = "0.2.16", features = ["js"] }
-gloo-timers = { version = "0.3.0", features = ["futures"] }
 
 # Bitcoin dependencies
 bdk_wallet = { version = "2.0.0" }

Cargo.toml

@@ -6,18 +6,25 @@ use bdk_wallet::{
     chain::spk_client::{FullScanRequest as BdkFullScanRequest, SyncRequest as BdkSyncRequest},
     KeychainKind,
 };
-use wasm_bindgen::prelude::wasm_bindgen;
+use wasm_bindgen::{
+    prelude::{wasm_bindgen, Closure},
+    JsCast, JsValue,
+};
+use wasm_bindgen_futures::JsFuture;
+use web_sys::js_sys::{Function, Promise};
 
 use crate::{
     result::JsResult,
     types::{FeeEstimates, FullScanRequest, SyncRequest, Transaction, Txid, Update},
 };
-use std::time::Duration;
+use std::{
+    future::Future,
+    pin::Pin,
+    task::{Context, Poll},
+    time::Duration,
+};
 
 use bdk_esplora::esplora_client::Sleeper;
-use gloo_timers::future::{sleep, TimeoutFuture};
-
-use crate::utils::SendSyncWrapper;
 
 #[wasm_bindgen]
 pub struct EsploraClient {
@@ -27,8 +34,10 @@ pub struct EsploraClient {
 #[wasm_bindgen]
 impl EsploraClient {
     #[wasm_bindgen(constructor)]
-    pub fn new(url: &str) -> JsResult<EsploraClient> {
-        let client = Builder::new(url).build_async_with_sleeper::<WebSleeper>()?;
+    pub fn new(url: &str, max_retries: usize) -> JsResult<EsploraClient> {
+        let client = Builder::new(url)
+            .max_retries(max_retries)
+            .build_async_with_sleeper::<WebSleeper>()?;
         Ok(EsploraClient { client })
     }
 
@@ -65,13 +74,34 @@ impl EsploraClient {
     }
 }
 
-#[derive(Clone)]
+struct WebSleep(JsFuture);
+
+impl Future for WebSleep {
+    type Output = ();
+    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<()> {
+        // delegate to the inner JsFuture
+        Pin::new(&mut self.get_mut().0).poll(cx).map(|_| ())
+    }
+}
+
+// SAFETY: Wasm is single-threaded; the value is never accessed concurrently.
+unsafe impl Send for WebSleep {}
+
+#[derive(Clone, Copy)]
 struct WebSleeper;
 
 impl Sleeper for WebSleeper {
-    type Sleep = SendSyncWrapper<TimeoutFuture>;
+    type Sleep = WebSleep;
 
     fn sleep(dur: Duration) -> Self::Sleep {
-        SendSyncWrapper(sleep(dur))
+        let ms = dur.as_millis() as i32;
+        let promise = Promise::new(&mut |resolve, _reject| {
+            let cb = Closure::once_into_js(move || resolve.call0(&JsValue::NULL).unwrap());
+            web_sys::window()
+                .unwrap()
+                .set_timeout_with_callback_and_timeout_and_arguments_0(cb.unchecked_ref::<Function>(), ms)
+                .unwrap();
+        });
+        WebSleep(JsFuture::from(promise))
     }
 }

src/bitcoin/esplora_client.rs

@@ -1,12 +1,10 @@
 mod descriptor;
-mod future;
 
 #[cfg(feature = "debug")]
 mod panic_hook;
 pub mod result;
 
 pub use descriptor::*;
-pub use future::SendSyncWrapper;
 
 #[cfg(feature = "debug")]
 pub use panic_hook::set_panic_hook;

src/utils/future.rs

@@ -23,7 +23,7 @@ async fn test_browser() {
         "wpkh(tprv8ZgxMBicQKsPe2qpAuh1K1Hig72LCoP4JgNxZM2ZRWHZYnpuw5oHoGBsQm7Qb8mLgPpRJVn3hceWgGQRNbPD6x1pp2Qme2YFRAPeYh7vmvE/84'/1'/0'/0/*)#a6kgzlgq".into(),
          "wpkh(tprv8ZgxMBicQKsPe2qpAuh1K1Hig72LCoP4JgNxZM2ZRWHZYnpuw5oHoGBsQm7Qb8mLgPpRJVn3hceWgGQRNbPD6x1pp2Qme2YFRAPeYh7vmvE/84'/1'/0'/1/*)#vwnfl2cc".into(),
     ).expect("wallet");
-    let blockchain_client = EsploraClient::new("https://mutinynet.com/api").expect("esplora_client");
+    let blockchain_client = EsploraClient::new("https://mutinynet.com/api", 6).expect("esplora_client");
 
     let block_height = wallet.latest_checkpoint().height();
     assert_eq!(block_height, 0);

src/utils/mod.rs

@@ -28,7 +28,7 @@ describe("Esplora client", () => {
 
   let feeRate: FeeRate;
   let wallet: Wallet;
-  const esploraClient = new EsploraClient(esploraUrl);
+  const esploraClient = new EsploraClient(esploraUrl, 0);
 
   it("creates a new wallet", () => {
     wallet = Wallet.create(network, externalDescriptor, internalDescriptor);