From 4f07343efdec27c97b2a3b5ee083aa84f3026022 Mon Sep 17 00:00:00 2001
From: Sachin Kamath <github@skamath.me>
Date: Tue, 17 Dec 2024 15:05:24 +0530
Subject: [PATCH] api: fetch addresses from config.

---
 nyx-chain-watcher/src/http/api/mod.rs     |  4 +-
 nyx-chain-watcher/src/http/api/server.rs  | 91 -----------------------
 nyx-chain-watcher/src/http/api/watcher.rs | 44 +++++++++++
 3 files changed, 47 insertions(+), 92 deletions(-)
 delete mode 100644 nyx-chain-watcher/src/http/api/server.rs
 create mode 100644 nyx-chain-watcher/src/http/api/watcher.rs

diff --git a/nyx-chain-watcher/src/http/api/mod.rs b/nyx-chain-watcher/src/http/api/mod.rs
index 145f07c9ee..9e405a439d 100644
--- a/nyx-chain-watcher/src/http/api/mod.rs
+++ b/nyx-chain-watcher/src/http/api/mod.rs
@@ -8,6 +8,7 @@ use utoipa_swagger_ui::SwaggerUi;
 use crate::http::{api_docs, server::HttpServer, state::AppState};
 
 pub(crate) mod price;
+pub(crate) mod watcher;
 
 pub(crate) struct RouterBuilder {
     unfinished_router: Router<AppState>,
@@ -24,7 +25,8 @@ impl RouterBuilder {
                 "/",
                 axum::routing::get(|| async { Redirect::permanent("/swagger") }),
             )
-            .nest("/v1", Router::new().nest("/price", price::routes()));
+            .nest("/v1", Router::new().nest("/price", price::routes()))
+            .nest("/v1", Router::new().nest("/watcher", watcher::routes()));
 
         Self {
             unfinished_router: router,
diff --git a/nyx-chain-watcher/src/http/api/server.rs b/nyx-chain-watcher/src/http/api/server.rs
deleted file mode 100644
index 92ac268eae..0000000000
--- a/nyx-chain-watcher/src/http/api/server.rs
+++ /dev/null
@@ -1,91 +0,0 @@
-use axum::Router;
-use core::net::SocketAddr;
-use tokio::{net::TcpListener, task::JoinHandle};
-use tokio_util::sync::{CancellationToken, WaitForCancellationFutureOwned};
-
-use crate::{
-    db::DbPool,
-    http::{api::RouterBuilder, state::AppState},
-};
-
-/// Return handles that allow for graceful shutdown of server + awaiting its
-/// background tokio task
-pub(crate) async fn start_http_api(
-    db_pool: DbPool,
-    http_port: u16,
-    nym_http_cache_ttl: u64,
-) -> anyhow::Result<ShutdownHandles> {
-    let router_builder = RouterBuilder::with_default_routes();
-
-    let state = AppState::new(db_pool, nym_http_cache_ttl);
-    let router = router_builder.with_state(state);
-
-    let bind_addr = format!("0.0.0.0:{}", http_port);
-    let server = router.build_server(bind_addr).await?;
-
-    Ok(start_server(server))
-}
-
-fn start_server(server: HttpServer) -> ShutdownHandles {
-    // one copy is stored to trigger a graceful shutdown later
-    let shutdown_button = CancellationToken::new();
-    // other copy is given to server to listen for a shutdown
-    let shutdown_receiver = shutdown_button.clone();
-    let shutdown_receiver = shutdown_receiver.cancelled_owned();
-
-    let server_handle = tokio::spawn(async move { server.run(shutdown_receiver).await });
-
-    ShutdownHandles {
-        server_handle,
-        shutdown_button,
-    }
-}
-
-pub(crate) struct ShutdownHandles {
-    server_handle: JoinHandle<std::io::Result<()>>,
-    shutdown_button: CancellationToken,
-}
-
-impl ShutdownHandles {
-    /// Send graceful shutdown signal to server and wait for server task to complete
-    pub(crate) async fn shutdown(self) -> anyhow::Result<()> {
-        self.shutdown_button.cancel();
-
-        match self.server_handle.await {
-            Ok(Ok(_)) => {
-                tracing::info!("HTTP server shut down without errors");
-            }
-            Ok(Err(err)) => {
-                tracing::error!("HTTP server terminated with: {err}");
-                anyhow::bail!(err)
-            }
-            Err(err) => {
-                tracing::error!("Server task panicked: {err}");
-            }
-        };
-
-        Ok(())
-    }
-}
-
-pub(crate) struct HttpServer {
-    router: Router,
-    listener: TcpListener,
-}
-
-impl HttpServer {
-    pub(crate) fn new(router: Router, listener: TcpListener) -> Self {
-        Self { router, listener }
-    }
-
-    pub(crate) async fn run(self, receiver: WaitForCancellationFutureOwned) -> std::io::Result<()> {
-        // into_make_service_with_connect_info allows us to see client ip address
-        axum::serve(
-            self.listener,
-            self.router
-                .into_make_service_with_connect_info::<SocketAddr>(),
-        )
-        .with_graceful_shutdown(receiver)
-        .await
-    }
-}
diff --git a/nyx-chain-watcher/src/http/api/watcher.rs b/nyx-chain-watcher/src/http/api/watcher.rs
new file mode 100644
index 0000000000..07c2d9c422
--- /dev/null
+++ b/nyx-chain-watcher/src/http/api/watcher.rs
@@ -0,0 +1,44 @@
+use crate::config::Config;
+use crate::http::error::Error;
+use crate::http::error::HttpResult;
+use crate::http::state::AppState;
+use axum::{Json, Router};
+
+pub(crate) fn routes() -> Router<AppState> {
+    Router::new().route("/addresses", axum::routing::get(get_addresses))
+}
+
+#[utoipa::path(
+    tag = "Watcher Configuration",
+    get,
+    path = "/v1/watcher/addresses",
+    responses(
+        (status = 200, body = Vec<String>)
+    )
+)]
+
+/// Fetch the addresses being watched by the chain watcher
+async fn get_addresses() -> HttpResult<Json<Vec<String>>> {
+    let config =
+        Config::read_from_toml_file_in_default_location().map_err(|_| Error::internal())?;
+
+    let addresses = config
+        .payment_watcher_config
+        .as_ref()
+        .and_then(|config| {
+            config.watchers.iter().find_map(|watcher| {
+                watcher
+                    .watch_for_transfer_recipient_accounts
+                    .as_ref()
+                    .map(|accounts| {
+                        accounts
+                            .iter()
+                            .map(|account| account.to_string())
+                            .collect::<Vec<_>>()
+                    })
+            })
+        })
+        .unwrap_or_default();
+
+    Ok(Json(addresses))
+}