rust_web_server/app/controller/metrics/
mod.rs

1#[cfg(test)]
2mod tests;
3
4use crate::controller::Controller;
5use crate::range::Range;
6use crate::request::{METHOD, Request};
7use crate::response::{Response, STATUS_CODE_REASON_PHRASE};
8use crate::server::ConnectionInfo;
9
10/// Prometheus metrics endpoint: `GET /metrics`.
11///
12/// Returns request counters and active-connection gauge in Prometheus
13/// text exposition format (`text/plain; version=0.0.4`).
14pub struct MetricsController;
15
16const PROMETHEUS_CONTENT_TYPE: &str = "text/plain; version=0.0.4";
17
18impl Controller for MetricsController {
19    fn is_matching(request: &Request, _connection: &ConnectionInfo) -> bool {
20        request.method == METHOD.get && request.request_uri == "/metrics"
21    }
22
23    fn process(_request: &Request, mut response: Response, _connection: &ConnectionInfo) -> Response {
24        MetricsController::fill_response(&mut response);
25        response
26    }
27}
28
29impl MetricsController {
30    fn fill_response(response: &mut Response) {
31        let body = crate::metrics::prometheus_text().into_bytes();
32        response.status_code = *STATUS_CODE_REASON_PHRASE.n200_ok.status_code;
33        response.reason_phrase = STATUS_CODE_REASON_PHRASE.n200_ok.reason_phrase.to_string();
34        response.content_range_list = vec![
35            Range::get_content_range(body, PROMETHEUS_CONTENT_TYPE.to_string())
36        ];
37    }
38
39    pub fn is_matching_request(request: &Request) -> bool {
40        request.method == METHOD.get && request.request_uri == "/metrics"
41    }
42
43    pub fn process_request(_request: &Request, mut response: Response) -> Response {
44        MetricsController::fill_response(&mut response);
45        response
46    }
47}
rust_web_server/app/controller/metrics/mod.rs

rust_web_server/app/controller/metrics/
mod.rs
