Use spawn_blocking() for database methods

zebra-scan/src/init.rs

@@ -4,18 +4,30 @@ use color_eyre::Report;
 use tokio::task::JoinHandle;
 use tracing::Instrument;
 
-use zebra_chain::parameters::Network;
+use zebra_chain::{diagnostic::task::WaitForPanics, parameters::Network};
 
 use crate::{scan, storage::Storage, Config};
 
-/// Initialize the scanner based on its config.
-pub fn init(
+/// Initialize the scanner based on its config, and spawn a task for it.
+///
+/// TODO: add a test for this function.
+pub fn spawn_init(
     config: &Config,
     network: Network,
     state: scan::State,
 ) -> JoinHandle<Result<(), Report>> {
-    let storage = Storage::new(config, network);
+    let config = config.clone();
+    tokio::spawn(init(config, network, state).in_current_span())
+}
+
+/// Initialize the scanner based on its config.
+///
+/// TODO: add a test for this function.
+pub async fn init(config: Config, network: Network, state: scan::State) -> Result<(), Report> {
+    let storage = tokio::task::spawn_blocking(move || Storage::new(&config, network))
+        .wait_for_panics()
+        .await;
 
     // TODO: add more tasks here?
-    tokio::spawn(scan::start(state, storage).in_current_span())
+    scan::start(state, storage).await
 }

zebra-scan/src/lib.rs

@@ -13,4 +13,4 @@ pub mod storage;
 mod tests;
 
 pub use config::Config;
-pub use init::init;
+pub use init::{init, spawn_init};

zebra-scan/src/storage/db/sapling.rs

@@ -37,6 +37,8 @@ impl Storage {
     // Reading Sapling database entries
 
     /// Returns the results for a specific key and block height.
+    //
+    // TODO: add tests for this method
     pub fn sapling_result_for_key_and_block(
         &self,
         index: &SaplingScannedDatabaseIndex,

zebrad/src/commands/start.rs

@@ -292,7 +292,7 @@ impl StartCmd {
         // Spawn never ending scan task.
         let scan_task_handle = {
             info!("spawning shielded scanner with configured viewing keys");
-            zebra_scan::init(&config.shielded_scan, config.network.network, state)
+            zebra_scan::spawn_init(&config.shielded_scan, config.network.network, state)
         };
 
         #[cfg(not(feature = "zebra-scan"))]