Update base images and introduce health endpoint (#3273)

* Update base images and introduce health endpoint

sync-server: introduce `/health` endpoint to check if the service is reachable.

bump(alpine): bump alpine base image from `3.19` to `3.20`

bump(rust): bump rust-alpine build image from `1.76` to `1.79`

* fix cargo fmt

* add allow clippy::extra_unused_type_parameters

* Remove unused type param (dae)

* Route /health directly (dae)

* Fix for latest axum (dae)

docs/syncserver/Dockerfile

@@ -1,14 +1,14 @@
-FROM rust:1.76-alpine3.19 AS builder
+FROM rust:1.79-alpine3.20 AS builder
 
 ARG ANKI_VERSION
 
 RUN apk update && apk add --no-cache build-base protobuf && rm -rf /var/cache/apk/*
 RUN cargo install --git https://github.com/ankitects/anki.git \
-    --tag ${ANKI_VERSION} \
-    --root /anki-server  \
-    anki-sync-server
+--tag ${ANKI_VERSION} \
+--root /anki-server  \
+anki-sync-server
 
-FROM alpine:3.19.1
+FROM alpine:3.20
 
 RUN adduser -D -h /home/anki anki
 
@@ -25,8 +25,9 @@ EXPOSE ${SYNC_PORT}
 
 CMD ["anki-sync-server"]
 
-# TODO - consider exposing endpoint /health to check on health cause currently it will return 404 error
-# HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
-#     CMD wget -qO- http://localhost:${SYNC_PORT} || exit 1
+# This health check will work for Anki versions 24.06.3 and newer.
+# For older versions, it may incorrectly report an unhealthy status, which should not be the case.
+HEALTHCHECK --interval=30s --timeout=10s --start-period=5s --retries=3 \
+    CMD wget -qO- http://localhost:${SYNC_PORT}/health || exit 1
 
 LABEL maintainer="Jean Khawand <jk@jeankhawand.com>"

rslib/src/sync/http_server/mod.rs

@@ -20,6 +20,7 @@ use std::sync::Mutex;
 
 use anki_io::create_dir_all;
 use axum::extract::DefaultBodyLimit;
+use axum::routing::get;
 use axum::Router;
 use axum_client_ip::SecureClientIpSource;
 use pbkdf2::password_hash::PasswordHash;
@@ -41,6 +42,7 @@ use crate::sync::error::OrHttpErr;
 use crate::sync::http_server::logging::with_logging_layer;
 use crate::sync::http_server::media_manager::ServerMediaManager;
 use crate::sync::http_server::routes::collection_sync_router;
+use crate::sync::http_server::routes::health_check_handler;
 use crate::sync::http_server::routes::media_sync_router;
 use crate::sync::http_server::user::User;
 use crate::sync::login::HostKeyRequest;
@@ -240,6 +242,7 @@ impl SimpleServer {
             Router::new()
                 .nest("/sync", collection_sync_router())
                 .nest("/msync", media_sync_router())
+                .route("/health", get(health_check_handler))
                 .with_state(server)
                 .layer(DefaultBodyLimit::max(*MAXIMUM_SYNC_PAYLOAD_BYTES))
                 .layer(config.ip_header.into_extension()),

rslib/src/sync/http_server/routes.rs

@@ -4,6 +4,8 @@
 use axum::extract::Path;
 use axum::extract::Query;
 use axum::extract::State;
+use axum::http::StatusCode;
+use axum::response::IntoResponse;
 use axum::response::Response;
 use axum::routing::get;
 use axum::routing::post;
@@ -86,6 +88,10 @@ async fn media_begin_post<P: MediaSyncProtocol>(
     media_sync_handler(Path(MediaSyncMethod::Begin), server, req.into_output_type()).await
 }
 
+pub async fn health_check_handler() -> impl IntoResponse {
+    StatusCode::OK
+}
+
 async fn media_sync_handler<P: MediaSyncProtocol>(
     Path(method): Path<MediaSyncMethod>,
     State(server): State<P>,