Added autounmount on stop. Added prom metrics to server 9090 /metrics

furumi-server/src/metrics.rs

@@ -0,0 +1,110 @@
+use once_cell::sync::Lazy;
+use prometheus::{
+    register_counter, register_counter_vec, register_gauge, register_histogram_vec,
+    Counter, CounterVec, Encoder, Gauge, HistogramVec, TextEncoder,
+};
+use std::time::Instant;
+
+// --- Counters ---
+
+pub static GRPC_REQUESTS_TOTAL: Lazy<CounterVec> = Lazy::new(|| {
+    register_counter_vec!(
+        "furumi_grpc_requests_total",
+        "Total number of gRPC requests",
+        &["method", "status"]
+    )
+    .unwrap()
+});
+
+pub static BYTES_READ_TOTAL: Lazy<Counter> = Lazy::new(|| {
+    register_counter!(
+        "furumi_bytes_read_total",
+        "Total number of bytes read from disk and streamed to clients"
+    )
+    .unwrap()
+});
+
+pub static FILE_OPEN_ERRORS_TOTAL: Lazy<Counter> = Lazy::new(|| {
+    register_counter!(
+        "furumi_file_open_errors_total",
+        "Total number of file open errors (not found, permission denied, etc.)"
+    )
+    .unwrap()
+});
+
+pub static AUTH_FAILURES_TOTAL: Lazy<Counter> = Lazy::new(|| {
+    register_counter!(
+        "furumi_auth_failures_total",
+        "Total number of authentication failures"
+    )
+    .unwrap()
+});
+
+// --- Histogram ---
+
+pub static GRPC_REQUEST_DURATION: Lazy<HistogramVec> = Lazy::new(|| {
+    register_histogram_vec!(
+        "furumi_grpc_request_duration_seconds",
+        "Duration of gRPC requests in seconds",
+        &["method"],
+        vec![0.0005, 0.001, 0.005, 0.01, 0.05, 0.1, 0.5, 1.0, 5.0, 10.0]
+    )
+    .unwrap()
+});
+
+// --- Gauges ---
+
+pub static ACTIVE_STREAMS: Lazy<Gauge> = Lazy::new(|| {
+    register_gauge!(
+        "furumi_active_streams",
+        "Number of currently active streaming connections (ReadFile/ReadDir)"
+    )
+    .unwrap()
+});
+
+/// Helper to track and record a gRPC call's duration and status.
+pub struct RequestTimer {
+    method: &'static str,
+    start: Instant,
+}
+
+impl RequestTimer {
+    pub fn new(method: &'static str) -> Self {
+        GRPC_REQUESTS_TOTAL
+            .with_label_values(&[method, "started"])
+            .inc();
+        Self {
+            method,
+            start: Instant::now(),
+        }
+    }
+
+    pub fn finish_ok(self) {
+        let elapsed = self.start.elapsed().as_secs_f64();
+        GRPC_REQUEST_DURATION
+            .with_label_values(&[self.method])
+            .observe(elapsed);
+        GRPC_REQUESTS_TOTAL
+            .with_label_values(&[self.method, "ok"])
+            .inc();
+    }
+
+    pub fn finish_err(self) {
+        let elapsed = self.start.elapsed().as_secs_f64();
+        GRPC_REQUEST_DURATION
+            .with_label_values(&[self.method])
+            .observe(elapsed);
+        GRPC_REQUESTS_TOTAL
+            .with_label_values(&[self.method, "error"])
+            .inc();
+    }
+}
+
+/// Render all registered metrics in Prometheus text format.
+pub fn render_metrics() -> String {
+    let encoder = TextEncoder::new();
+    let metric_families = prometheus::gather();
+    let mut buffer = Vec::new();
+    encoder.encode(&metric_families, &mut buffer).unwrap();
+    String::from_utf8(buffer).unwrap()
+}