Feat: add infinite Cardano transactions preloader in signer

mithril-signer/src/configuration.rs

@@ -116,6 +116,9 @@ pub struct Configuration {
 
     /// The maximum number of roll forwards during a poll of the block streamer when importing transactions.
     pub cardano_transactions_block_streamer_max_roll_forwards_per_poll: usize,
+
+    /// Preloading refresh interval in seconds
+    pub preloading_refresh_interval: u64,
 }
 
 impl Configuration {
@@ -153,6 +156,7 @@ impl Configuration {
             enable_transaction_pruning: false,
             transactions_import_block_chunk_size: BlockNumber(1000),
             cardano_transactions_block_streamer_max_roll_forwards_per_poll: 1000,
+            preloading_refresh_interval: 60,
         }
     }
 

mithril-signer/src/main.rs

@@ -3,7 +3,7 @@ use clap::{CommandFactory, Parser, Subcommand};
 use config::{Map, Value};
 
 use slog::{o, Drain, Level, Logger};
-use slog_scope::{crit, debug};
+use slog_scope::{crit, debug, info};
 use std::path::PathBuf;
 use std::sync::Arc;
 use std::time::Duration;
@@ -80,6 +80,11 @@ pub struct Args {
     /// Will be ignored on (pre)production networks.
     #[clap(long)]
     allow_unparsable_block: bool,
+
+    /// Preloading refresh interval in seconds
+    // TODO: Replace the default value to 43200 (12 hours) once the Cardano transactions is activated on mainnet
+    #[clap(long, env = "PRELOADING_REFRESH_INTERVAL", default_value_t = 7200)]
+    preloading_refresh_interval: u64,
 }
 
 impl Args {
@@ -184,7 +189,17 @@ async fn main() -> StdResult<()> {
             .map(|_| None)
     });
 
-    let preload_task = tokio::spawn(async move { cardano_transaction_preloader.preload().await });
+    join_set.spawn(async move {
+        let refresh_interval = config.preloading_refresh_interval;
+        let mut interval = tokio::time::interval(Duration::from_secs(refresh_interval));
+        loop {
+            interval.tick().await;
+            if let Err(err) = cardano_transaction_preloader.preload().await {
+                crit!("🔥 Cardano transactions preloader failed: {err:?}");
+            }
+            info!("⟳ Next Preload Cardano Transactions will start in {refresh_interval} s",);
+        }
+    });
 
     let (metrics_server_shutdown_tx, metrics_server_shutdown_rx) = oneshot::channel();
     if config.enable_metrics_server {
@@ -239,10 +254,6 @@ async fn main() -> StdResult<()> {
         .send(())
         .map_err(|e| anyhow!("Metrics server shutdown signal could not be sent: {e:?}"))?;
 
-    if !preload_task.is_finished() {
-        preload_task.abort();
-    }
-
     join_set.shutdown().await;
 
     debug!("Stopping"; "shutdown_reason" => shutdown_reason);

mithril-test-lab/mithril-end-to-end/src/mithril/signer.rs

@@ -70,6 +70,7 @@ impl Signer {
             ),
             ("ERA_READER_ADAPTER_PARAMS", &era_reader_adapter_params),
             ("TRANSACTIONS_IMPORT_BLOCK_CHUNK_SIZE", "150"),
+            ("PRELOADING_REFRESH_INTERVAL", "10"),
         ]);
         if signer_config.enable_certification {
             env.insert(