use axum::{
body::Body,
extract::MatchedPath,
http::Request,
middleware::Next,
response::{IntoResponse, Response},
routing::get,
Router,
};
use lazy_static::lazy_static;
use prometheus::{
register_histogram_vec, register_int_counter_vec, Encoder, HistogramVec, IntCounterVec,
TextEncoder,
};
use std::sync::Arc;
use std::time::Instant;
use crate::AppState;
lazy_static! {
pub static ref HTTP_REQUESTS_TOTAL: IntCounterVec = register_int_counter_vec!(
"nora_http_requests_total",
"Total number of HTTP requests",
&["registry", "method", "status"]
).expect("metric can be created");
pub static ref HTTP_REQUEST_DURATION: HistogramVec = register_histogram_vec!(
"nora_http_request_duration_seconds",
"HTTP request latency in seconds",
&["registry", "method"],
vec![0.001, 0.005, 0.01, 0.025, 0.05, 0.1, 0.25, 0.5, 1.0, 2.5, 5.0, 10.0]
).expect("metric can be created");
pub static ref CACHE_REQUESTS: IntCounterVec = register_int_counter_vec!(
"nora_cache_requests_total",
"Total cache requests",
&["registry", "result"]
).expect("metric can be created");
pub static ref STORAGE_OPERATIONS: IntCounterVec = register_int_counter_vec!(
"nora_storage_operations_total",
"Total storage operations",
&["operation", "status"]
).expect("metric can be created");
pub static ref ARTIFACTS_TOTAL: IntCounterVec = register_int_counter_vec!(
"nora_artifacts_total",
"Total artifacts stored",
&["registry"]
).expect("metric can be created");
}
pub fn routes() -> Router<Arc<AppState>> {
Router::new().route("/metrics", get(metrics_handler))
}
async fn metrics_handler() -> impl IntoResponse {
let encoder = TextEncoder::new();
let metric_families = prometheus::gather();
let mut buffer = Vec::new();
encoder
.encode(&metric_families, &mut buffer)
.unwrap_or_default();
([("content-type", "text/plain; charset=utf-8")], buffer)
}
pub async fn metrics_middleware(
matched_path: Option<MatchedPath>,
request: Request<Body>,
next: Next,
) -> Response {
let start = Instant::now();
let method = request.method().to_string();
let path = matched_path
.map(|p| p.as_str().to_string())
.unwrap_or_else(|| request.uri().path().to_string());
let registry = detect_registry(&path);
let response = next.run(request).await;
let duration = start.elapsed().as_secs_f64();
let status = response.status().as_u16().to_string();
HTTP_REQUESTS_TOTAL
.with_label_values(&[®istry, &method, &status])
.inc();
HTTP_REQUEST_DURATION
.with_label_values(&[®istry, &method])
.observe(duration);
response
}
fn detect_registry(path: &str) -> String {
if path.starts_with("/v2") {
"docker".to_string()
} else if path.starts_with("/maven2") {
"maven".to_string()
} else if path.starts_with("/npm") {
"npm".to_string()
} else if path.starts_with("/cargo") {
"cargo".to_string()
} else if path.starts_with("/simple") || path.starts_with("/packages") {
"pypi".to_string()
} else if path.starts_with("/ui") {
"ui".to_string()
} else {
"other".to_string()
}
}
#[allow(dead_code)]
pub fn record_cache_hit(registry: &str) {
CACHE_REQUESTS.with_label_values(&[registry, "hit"]).inc();
}
#[allow(dead_code)]
pub fn record_cache_miss(registry: &str) {
CACHE_REQUESTS.with_label_values(&[registry, "miss"]).inc();
}
#[allow(dead_code)]
pub fn record_storage_op(operation: &str, success: bool) {
let status = if success { "success" } else { "error" };
STORAGE_OPERATIONS
.with_label_values(&[operation, status])
.inc();
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_detect_registry_docker() {
assert_eq!(detect_registry("/v2/nginx/manifests/latest"), "docker");
assert_eq!(detect_registry("/v2/"), "docker");
assert_eq!(
detect_registry("/v2/library/alpine/blobs/sha256:abc"),
"docker"
);
}
#[test]
fn test_detect_registry_maven() {
assert_eq!(detect_registry("/maven2/com/example/artifact"), "maven");
}
#[test]
fn test_detect_registry_npm() {
assert_eq!(detect_registry("/npm/lodash"), "npm");
assert_eq!(detect_registry("/npm/@scope/package"), "npm");
}
#[test]
fn test_detect_registry_cargo() {
assert_eq!(detect_registry("/cargo/api/v1/crates"), "cargo");
}
#[test]
fn test_detect_registry_pypi() {
assert_eq!(detect_registry("/simple/requests/"), "pypi");
assert_eq!(
detect_registry("/packages/requests/1.0/requests-1.0.tar.gz"),
"pypi"
);
}
#[test]
fn test_detect_registry_ui() {
assert_eq!(detect_registry("/ui/dashboard"), "ui");
assert_eq!(detect_registry("/ui"), "ui");
}
#[test]
fn test_detect_registry_other() {
assert_eq!(detect_registry("/health"), "other");
assert_eq!(detect_registry("/ready"), "other");
assert_eq!(detect_registry("/unknown/path"), "other");
}
}