feat: improve fetcher

Cargo.toml

@@ -4,21 +4,26 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-axum = "0.8.6"
-tokio = { version = "1.48.0", features = ["full"] }
+axum = "0.8.9"
+reqwest = { version = "0.13.3", features = ["json"] }
+tokio = { version = "1.52.1", features = ["full"] }
 serde = { version = "1.0", features = ["derive"] }
 futures = "0.3"
 tokio-stream = "0.1"
-clap = { version = "4.5.51", features = ["env", "derive"] }
-alloy = { version = "1.7.3", features = ["provider-ws"] }
-thiserror = "2.0.17"
+clap = { version = "4.6.1", features = ["env", "derive"] }
+alloy = { version = "2.0.4", features = ["provider-ws", "getrandom"] }
+thiserror = "2.0.18"
 tracing = "0.1.43"
 tracing-subscriber = { version = "0.3.22", features = ["json", "env-filter"] }
 tokio-util = { version = "0.7.17" }
 tower-http = { version = "0.6", features = ["cors"] }
 
-metrics = "0.24"
-metrics-exporter-prometheus = "0.16"
-rustls = { version = "0.23", features = ["ring"], default-features = false }
+metrics = "0.24.5"
+metrics-exporter-prometheus = "0.18.3"
+rustls = { version = "0.23.40", features = ["ring"], default-features = false }
 backon = "1"
-uuid = { version = "1.22.0", features = ["v4"] }
+uuid = { version = "1.23.1", features = ["v4"] }
+
+[dev-dependencies]
+wiremock = "0.6.5"
+serde_json="1.0.149"

src/config/back_off_config.rs

@@ -0,0 +1,14 @@
+use backon::ExponentialBuilder;
+use std::time::Duration;
+
+const TOKEN_LIST_FETCHER_BACKOFFS: usize = 3;
+
+// token list fetcher backoff configuration
+// needed to handle errors when load token list
+pub fn get_token_list_fetcher_backoff() -> ExponentialBuilder {
+    ExponentialBuilder::default()
+        .with_min_delay(Duration::from_secs(1))
+        .with_max_delay(Duration::from_secs(3))
+        .with_max_times(TOKEN_LIST_FETCHER_BACKOFFS)
+        .with_jitter()
+}

src/config/constants.rs

@@ -1,8 +1,5 @@
 use std::time::Duration;
 
-/// Maximum number of concurrent HTTP requests when fetching token lists
-pub const TOKEN_FETCH_CONCURRENCY: usize = 5;
-
 /// Capacity of the broadcast channel for balance events per subscription
 pub const BROADCAST_CHANNEL_CAPACITY: usize = 256;
 

src/config/mod.rs

@@ -1,2 +1,3 @@
+pub mod back_off_config;
 pub mod constants;
 pub mod network_config;

src/domain/token.rs

@@ -5,7 +5,5 @@ use serde::{Deserialize, Serialize};
 #[serde(rename_all = "camelCase")]
 pub struct Token {
     pub address: Address,
-    pub name: String,
-    pub decimals: u8,
     pub chain_id: u64,
 }

src/services/session_manager.rs

@@ -1,3 +1,4 @@
+use crate::config::back_off_config::get_token_list_fetcher_backoff;
 use crate::domain::{BalanceEvent, EvmNetwork, Session};
 use crate::services::balance_fetcher::BalanceFetcher;
 use crate::services::cleanup_stream;
@@ -19,9 +20,11 @@ use serde::Serialize;
 use std::collections::{HashMap, HashSet};
 use std::convert::Infallible;
 use std::sync::Arc;
-use std::time::Instant;
+use std::time::{Duration, Instant};
 use tokio_stream::wrappers::BroadcastStream;
 
+const TOKEN_LIST_CACHE_TTL: Duration = Duration::from_hours(5);
+
 // handle subscriptions: fetch token lists, spawn watchers, update watched tokens
 pub struct SessionManager {
     sub_manager: Arc<SubscriptionManager>,
@@ -95,7 +98,8 @@ impl SessionManager {
         snapshot_interval: usize,
         token_limit: usize,
     ) -> Self {
-        let token_list_fetcher = TokenListFetcher::new();
+        let token_list_fetcher =
+            TokenListFetcher::new(TOKEN_LIST_CACHE_TTL, get_token_list_fetcher_backoff());
 
         let sub_manager = Arc::new(SubscriptionManager::new());
         Arc::clone(&sub_manager).spawn_cleanup();