ci: [torrust#384] add container healthcheck for index service

Containerfile

@@ -85,7 +85,9 @@ COPY --from=build \
 RUN cargo nextest run --workspace-remap /test/src/ --extract-to /test/src/ --no-run --archive-file /test/torrust-index.tar.zst
 RUN cargo nextest run --workspace-remap /test/src/ --target-dir-remap /test/src/target/ --cargo-metadata /test/src/target/nextest/cargo-metadata.json --binaries-metadata /test/src/target/nextest/binaries-metadata.json
 
-RUN mkdir -p /app/bin/; cp -l /test/src/target/release/torrust-index /app/bin/torrust-index
+RUN mkdir -p /app/bin/; \
+  cp -l /test/src/target/release/torrust-index /app/bin/torrust-index; \
+  cp -l /test/src/target/release/health_check /app/bin/health_check;
 # RUN mkdir -p /app/lib/; cp -l $(realpath $(ldd /app/bin/torrust-index | grep "libz\.so\.1" | awk '{print $3}')) /app/lib/libz.so.1
 RUN chown -R root:root /app; chmod -R u=rw,go=r,a+X /app; chmod -R a+x /app/bin
 
@@ -99,11 +101,13 @@ ARG TORRUST_INDEX_PATH_CONFIG="/etc/torrust/index/index.toml"
 ARG TORRUST_INDEX_DATABASE_DRIVER="sqlite3"
 ARG USER_ID=1000
 ARG API_PORT=3001
+ARG HEALTH_CHECK_PORT=3002
 
 ENV TORRUST_INDEX_PATH_CONFIG=${TORRUST_INDEX_PATH_CONFIG}
 ENV TORRUST_INDEX_DATABASE_DRIVER=${TORRUST_INDEX_DATABASE_DRIVER}
 ENV USER_ID=${USER_ID}
 ENV API_PORT=${API_PORT}
+ENV HEALTH_CHECK_PORT=${HEALTH_CHECK_PORT}
 ENV TZ=Etc/UTC
 
 EXPOSE ${API_PORT}/tcp
@@ -130,5 +134,6 @@ CMD ["sh"]
 FROM runtime as release
 ENV RUNTIME="release"
 COPY --from=test /app/ /usr/
-# HEALTHCHECK CMD ["/usr/bin/wget", "--no-verbose", "--tries=1", "--spider", "localhost:${API_PORT}/version"]
+HEALTHCHECK --interval=5s --timeout=5s --start-period=3s --retries=3 \  
+  CMD /usr/bin/health_check  http://localhost:${HEALTH_CHECK_PORT}/health_check || exit 1
 CMD ["/usr/bin/torrust-index"]

contrib/dev-tools/container/e2e/mysql/run-e2e-tests.sh

@@ -25,10 +25,10 @@ echo "Running E2E tests using MySQL ..."
 ./contrib/dev-tools/container/e2e/mysql/e2e-env-up.sh || exit 1
 
 # Wait for conatiners to be healthy
-./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh torrust-mysql-1 10 3
-# todo: implement healthchecks for tracker and index and wait until they are healthy
-#wait_for_container torrust-tracker-1 10 3
-#wait_for_container torrust-idx-back-1 10 3
+./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh torrust-mysql-1 10 3 || exit 1
+# todo: implement healthchecks for the tracker and wait until it's healthy
+#./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh torrust-tracker-1 10 3
+./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh  torrust-index-1 10 3 || exit 1
 sleep 20s
 
 # Just to make sure that everything is up and running

contrib/dev-tools/container/e2e/sqlite/run-e2e-tests.sh

@@ -26,10 +26,10 @@ echo "Running E2E tests using SQLite ..."
 ./contrib/dev-tools/container/e2e/sqlite/e2e-env-up.sh || exit 1
 
 # Wait for conatiners to be healthy
-./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh torrust-mysql-1 10 3
-# todo: implement healthchecks for tracker and index and wait until they are healthy
-#wait_for_container torrust-tracker-1 10 3
-#wait_for_container torrust-idx-back-1 10 3
+./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh torrust-mysql-1 10 3 || exit 1
+# todo: implement healthchecks for the tracker and wait until it's healthy
+#./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh torrust-tracker-1 10 3
+./contrib/dev-tools/container/functions/wait_for_container_to_be_healthy.sh  torrust-index-1 10 3 || exit 1
 sleep 20s
 
 # Just to make sure that everything is up and running

src/app.rs

@@ -1,6 +1,10 @@
 use std::net::SocketAddr;
 use std::sync::Arc;
 
+use axum::routing::get;
+use axum::{Json, Router};
+use log::info;
+use serde_json::{json, Value};
 use tokio::task::JoinHandle;
 
 use crate::bootstrap::logging;
@@ -22,6 +26,8 @@ use crate::web::api::v1::auth::Authentication;
 use crate::web::api::{start, Version};
 use crate::{mailer, tracker};
 
+const HEALTH_CHECK_PORT: u16 = 3002;
+
 pub struct Running {
     pub api_socket_addr: SocketAddr,
     pub api_server: Option<JoinHandle<std::result::Result<(), std::io::Error>>>,
@@ -159,6 +165,8 @@ pub async fn run(configuration: Configuration, api_version: &Version) -> Running
     let weak_tracker_statistics_importer = Arc::downgrade(&tracker_statistics_importer);
 
     let tracker_statistics_importer_handle = tokio::spawn(async move {
+        info!("Tracker statistics importer started");
+
         let interval = std::time::Duration::from_secs(torrent_info_update_interval);
         let mut interval = tokio::time::interval(interval);
         interval.tick().await; // first tick is immediate...
@@ -173,12 +181,42 @@ pub async fn run(configuration: Configuration, api_version: &Version) -> Running
     });
 
     // Start API server
-
     let running_api = start(app_data, &net_ip, net_port, api_version).await;
 
-    Running {
+    // Full running application
+    let app = Running {
         api_socket_addr: running_api.socket_addr,
         api_server: running_api.api_server,
         tracker_data_importer_handle: tracker_statistics_importer_handle,
-    }
+    };
+
+    // Start Health Checker
+    // This must be done after launching the other services because it does not
+    // re-check the health of all services.
+    let _health_check_handle = tokio::spawn(async move {
+        let app = Router::new().route("/health_check", get(get(health_check)));
+
+        let addr = format!("127.0.0.1:{HEALTH_CHECK_PORT}");
+
+        info!("Health checker listening on http://{}/health_check", addr);
+
+        axum::Server::bind(&addr.parse().unwrap())
+            .serve(app.into_make_service())
+            .await
+            .unwrap();
+    });
+
+    app
+}
+
+/// It runs a health check on the application.
+///
+/// For the time being, we only return ok if the application services were
+/// launched. This services has to be launched after launching all the other
+/// application services.
+///
+/// It's used for container health check when the application is containerized.
+async fn health_check() -> Json<Value> {
+    // todo: check that services are healthy
+    Json(json!({ "status": "Ok" }))
 }

src/bin/health_check.rs

@@ -0,0 +1,34 @@
+//! Command line tool to parse a torrent file and print the decoded torrent.
+//!
+//! It's only used for debugging purposes.
+use std::{env, process};
+
+#[tokio::main]
+async fn main() {
+    let args: Vec<String> = env::args().collect();
+    if args.len() != 2 {
+        eprintln!("Usage:   cargo run --bin health_check <HEALTH_URL>");
+        eprintln!("Example: cargo run --bin health_check http://localhost:3002/health_check");
+        std::process::exit(1);
+    }
+
+    println!("Health check ...");
+
+    let url = &args[1].clone();
+
+    match reqwest::get(url).await {
+        Ok(response) => {
+            if response.status().is_success() {
+                println!("STATUS: {}", response.status());
+                process::exit(0);
+            } else {
+                println!("Non-success status received.");
+                process::exit(1);
+            }
+        }
+        Err(err) => {
+            println!("ERROR: {err}");
+            process::exit(1);
+        }
+    }
+}