From e0c8c1ba3da0a65a3dd2681d3b7802c1c09cc4a1 Mon Sep 17 00:00:00 2001
From: Juraj Piar <juraj@iovlabs.org>
Date: Fri, 15 Sep 2023 10:43:48 +0100
Subject: [PATCH] feat(ticker): modifies dev ticker to proxy to coingecko

---
 .../src/bin/providers/dev_price_provider.rs   | 92 +++++++++++++++++--
 1 file changed, 84 insertions(+), 8 deletions(-)

diff --git a/core/bin/zksync_api/src/bin/providers/dev_price_provider.rs b/core/bin/zksync_api/src/bin/providers/dev_price_provider.rs
index 2dd68aa87..06470a3f3 100644
--- a/core/bin/zksync_api/src/bin/providers/dev_price_provider.rs
+++ b/core/bin/zksync_api/src/bin/providers/dev_price_provider.rs
@@ -3,11 +3,15 @@
 //! Implements coinmarketcap API for tokens deployed using `deploy-dev-erc20`
 //! Prices are randomly distributed around base values estimated from real world prices.
 
-use actix_web::{web, HttpRequest, HttpResponse, Result};
+use actix_web::{web, HttpRequest, HttpResponse, Result, Scope};
 use bigdecimal::BigDecimal;
 use chrono::{SecondsFormat, Utc};
+use jsonrpc_ws_server::ws::Handler;
+use reqwest::Client;
 use serde::{Deserialize, Serialize};
-use serde_json::json;
+use serde_json::{json, Value};
+use std::sync::{Arc, Mutex};
+use std::time::Instant;
 use std::{collections::HashMap, fs::read_to_string, path::Path};
 use std::{convert::TryFrom, time::Duration};
 use zksync_crypto::rand::{thread_rng, Rng};
@@ -18,6 +22,77 @@ struct CoinMarketCapTokenQuery {
     symbol: String,
 }
 
+struct Cache<T> {
+    data: T,
+    last_fetched: Instant,
+}
+
+#[derive(Clone)]
+struct ProxyState {
+    cache: Arc<Mutex<HashMap<String, Cache<Value>>>>,
+}
+
+async fn fetch_coins_list(data: web::Data<ProxyState>, path: web::Path<(bool,)>) -> HttpResponse {
+    let include_platform = path.0.clone();
+    let url = format!(
+        "https://api.coingecko.com/api/v3/coins/list?include_platform={}",
+        include_platform
+    );
+    proxy_request(&url, &data.cache).await
+}
+
+async fn fetch_market_chart(
+    data: web::Data<ProxyState>,
+    path: web::Path<(String,)>,
+) -> HttpResponse {
+    let coin = path.0.clone();
+    let url = format!(
+        "https://api.coingecko.com/api/v3/coins/{}/market_chart",
+        coin
+    );
+    proxy_request(&url, &data.cache).await
+}
+
+async fn fetch_coin_market_cap(data: web::Data<ProxyState>) -> HttpResponse {
+    proxy_request(
+        "https://pro-api.coinmarketcap.com/v1/cryptocurrency/quotes/latest",
+        &data.cache,
+    )
+    .await
+}
+
+async fn proxy_request(url: &str, cache: &Mutex<HashMap<String, Cache<Value>>>) -> HttpResponse {
+    let mut lock = cache.lock().unwrap();
+
+    // Check cache first
+    if let Some(cached) = lock.get(url) {
+        if cached.last_fetched.elapsed() < Duration::from_secs(5) {
+            // TODO: configure timeout (or use existing one)
+            return HttpResponse::Ok().json(&cached.data);
+        }
+    }
+
+    // Fetch data if not in cache or stale
+    let client = Client::new();
+    match client.get(url).send().await {
+        Ok(response) => match response.json::<Value>().await {
+            Ok(data) => {
+                // Cache the fetched data
+                lock.insert(
+                    url.to_string(),
+                    Cache {
+                        data: data.clone(),
+                        last_fetched: Instant::now(),
+                    },
+                );
+                HttpResponse::Ok().json(data)
+            }
+            Err(_) => HttpResponse::InternalServerError().finish(),
+        },
+        Err(_) => HttpResponse::InternalServerError().finish(),
+    }
+}
+
 macro_rules! make_sloppy {
     ($f: ident) => {{
         |query, data| async {
@@ -176,6 +251,9 @@ pub fn create_price_service(sloppy_mode: bool) -> actix_web::Scope {
         .into_iter()
         .chain(testnet_tokens.into_iter())
         .collect();
+
+    // When sloppy mode is enabled, we are more tolerant of errors and we use
+    // a fake API that returns random prices. This is useful for testing.
     if sloppy_mode {
         web::scope("")
             .app_data(web::Data::new(data))
@@ -192,19 +270,17 @@ pub fn create_price_service(sloppy_mode: bool) -> actix_web::Scope {
                 web::get().to(make_sloppy!(handle_coingecko_token_price_query)),
             )
     } else {
+        // TODO: allow non-sloppy mode for dev env (ei move the proxy to its own service)
         web::scope("")
             .app_data(web::Data::new(data))
             .route(
                 "/cryptocurrency/quotes/latest",
-                web::get().to(handle_coinmarketcap_token_price_query),
-            )
-            .route(
-                "/api/v3/coins/list",
-                web::get().to(handle_coingecko_token_list),
+                web::get().to(fetch_coin_market_cap),
             )
+            .route("/api/v3/coins/list", web::get().to(fetch_coins_list))
             .route(
                 "/api/v3/coins/{coin_id}/market_chart",
-                web::get().to(handle_coingecko_token_price_query),
+                web::get().to(fetch_market_chart),
             )
     }
 }