prometheus and grafana dashboards implemented

Cargo.lock

@@ -2048,6 +2048,7 @@ dependencies = [
  "indexmap",
  "itertools",
  "jsonwebtoken",
+ "lazy_static",
  "log",
  "manifest-dir-macros",
  "maplit",
@@ -2061,6 +2062,7 @@ dependencies = [
  "parking_lot",
  "pin-project-lite",
  "platform-dirs",
+ "prometheus",
  "rand",
  "rayon",
  "regex",
@@ -2667,6 +2669,36 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "procfs"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0941606b9934e2d98a3677759a971756eb821f75764d0e0d26946d08e74d9104"
+dependencies = [
+ "bitflags",
+ "byteorder",
+ "hex",
+ "lazy_static",
+ "libc",
+]
+
+[[package]]
+name = "prometheus"
+version = "0.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cface98dfa6d645ea4c789839f176e4b072265d085bfcc48eaa8d137f58d3c39"
+dependencies = [
+ "cfg-if 1.0.0",
+ "fnv",
+ "lazy_static",
+ "libc",
+ "memchr",
+ "parking_lot",
+ "procfs",
+ "protobuf",
+ "thiserror",
+]
+
 [[package]]
 name = "proptest"
 version = "1.0.0"
@@ -2698,6 +2730,12 @@ dependencies = [
  "syn 0.15.44",
 ]
 
+[[package]]
+name = "protobuf"
+version = "2.27.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cf7e6d18738ecd0902d30d1ad232c9125985a3422929b16c65517b38adc14f96"
+
 [[package]]
 name = "quick-error"
 version = "1.2.3"

meilisearch-http/Cargo.toml

@@ -77,6 +77,8 @@ tokio = { version = "1.17.0", features = ["full"] }
 tokio-stream = "0.1.8"
 uuid = { version = "1.1.2", features = ["serde", "v4"] }
 walkdir = "2.3.2"
+prometheus = { version = "0.13.0", features = ["process"] }
+lazy_static = "1.4.0"
 
 [dev-dependencies]
 actix-rt = "2.7.0"

meilisearch-http/src/lib.rs

@@ -7,6 +7,7 @@ pub mod task;
 pub mod extractors;
 pub mod option;
 pub mod routes;
+pub mod metrics;
 
 use std::sync::{atomic::AtomicBool, Arc};
 use std::time::Duration;
@@ -146,16 +147,48 @@ macro_rules! create_app {
         use actix_cors::Cors;
         use actix_web::middleware::TrailingSlash;
         use actix_web::App;
+        use actix_web::dev::Service;
         use actix_web::{middleware, web};
         use meilisearch_http::error::MeilisearchHttpError;
         use meilisearch_http::routes;
         use meilisearch_http::{configure_data, dashboard};
         use meilisearch_types::error::ResponseError;
+        use meilisearch_http::metrics;
+
+        use lazy_static::lazy_static;
+        use prometheus::{opts, register_histogram_vec, register_int_counter_vec, register_int_gauge};
+        use prometheus::{HistogramVec, IntCounterVec, IntGauge, HistogramTimer};
 
         App::new()
             .configure(|s| configure_data(s, $data.clone(), $auth.clone(), &$opt, $analytics))
             .configure(routes::configure)
             .configure(|s| dashboard(s, $enable_frontend))
+            .wrap_fn(|req, srv| {
+                let mut histogram_timer: Option<HistogramTimer> = None;
+                let request_path = req.path();
+                let is_registered_resource = req.resource_map().has_resource(request_path);
+                if is_registered_resource {
+                    let request_method = req.method().to_string();
+                    histogram_timer = Some(
+                        metrics::HTTP_RESPONSE_TIME_SECONDS
+                            .with_label_values(&[&request_method, request_path])
+                            .start_timer(),
+                    );
+                    metrics::HTTP_REQUESTS_TOTAL
+                        .with_label_values(&[&request_method, request_path])
+                        .inc();
+                }
+
+                let fut = srv.call(req);
+
+                async {
+                    let res = fut.await?;
+                    if let Some(histogram_timer) = histogram_timer {
+                        histogram_timer.observe_duration();
+                    };
+                    Ok(res)
+                }
+            })
             .wrap(
                 Cors::default()
                     .send_wildcard()

meilisearch-http/src/metrics.rs

@@ -0,0 +1,40 @@
+use lazy_static::lazy_static;
+use prometheus::{opts, register_histogram_vec, register_int_counter_vec, register_int_gauge, register_int_gauge_vec};
+use prometheus::{HistogramVec, IntCounterVec, IntGauge, IntGaugeVec};
+
+const HTTP_RESPONSE_TIME_CUSTOM_BUCKETS: &[f64; 14] = &[
+    0.0005, 0.0008, 0.00085, 0.0009, 0.00095, 0.001, 0.00105, 0.0011, 0.00115, 0.0012, 0.0015,
+    0.002, 0.003, 1.0,
+];
+
+lazy_static! {
+    pub static ref HTTP_REQUESTS_TOTAL: IntCounterVec = register_int_counter_vec!(
+        opts!("http_requests_total", "HTTP requests total"),
+        &["method", "path"]
+    )
+    .expect("Can't create a metric");
+
+    pub static ref MEILISEARCH_DB_SIZE: IntGauge = register_int_gauge!(
+        opts!("meilisearch_database_size", "MeiliSearch Stats DbSize")
+    )
+    .expect("Can't create a metric");
+
+    pub static ref MEILISEARCH_INDEX_COUNT: IntGauge = register_int_gauge!(
+        opts!("meilisearch_total_index", "MeiliSearch Stats Index Count")
+    )
+    .expect("Can't create a metric");
+
+    pub static ref MEILISEARCH_DOCS_COUNT: IntGaugeVec = register_int_gauge_vec!(
+        opts!("meilisearch_docs_count", "MeiliSearch Stats Docs Count"),
+        &["index"]
+    )
+    .expect("Can't create a metric");
+
+    pub static ref HTTP_RESPONSE_TIME_SECONDS: HistogramVec = register_histogram_vec!(
+        "http_response_time_seconds",
+        "HTTP response times",
+        &["method", "path"],
+        HTTP_RESPONSE_TIME_CUSTOM_BUCKETS.to_vec()
+    )
+    .expect("Can't create a metric");
+}

meilisearch-http/src/routes/mod.rs

@@ -1,4 +1,5 @@
-use actix_web::{web, HttpRequest, HttpResponse};
+use actix_web::{web, HttpResponse};
+use actix_web::http::header::{self};
 use log::debug;
 use serde::{Deserialize, Serialize};
 
@@ -12,6 +13,7 @@ use meilisearch_types::star_or::StarOr;
 
 use crate::analytics::Analytics;
 use crate::extractors::authentication::{policies::*, GuardedData};
+use prometheus::{Encoder, TextEncoder};
 
 mod api_key;
 mod dump;
@@ -21,6 +23,7 @@ mod tasks;
 pub fn configure(cfg: &mut web::ServiceConfig) {
     cfg.service(web::scope("/tasks").configure(tasks::configure))
         .service(web::resource("/health").route(web::get().to(get_health)))
+        .service(web::resource("/metrics").route(web::get().to(get_metrics)))
         .service(web::scope("/keys").configure(api_key::configure))
         .service(web::scope("/dumps").configure(dump::configure))
         .service(web::resource("/stats").route(web::get().to(get_stats)))
@@ -278,3 +281,36 @@ struct KeysResponse {
 pub async fn get_health() -> Result<HttpResponse, ResponseError> {
     Ok(HttpResponse::Ok().json(serde_json::json!({ "status": "available" })))
 }
+
+pub async fn get_metrics(
+    meilisearch: GuardedData<ActionPolicy<{ actions::STATS_GET }>, MeiliSearch>,
+) -> Result<HttpResponse, ResponseError> {
+
+    let search_rules = &meilisearch.filters().search_rules;
+    let response = meilisearch.get_all_stats(search_rules).await?;
+
+    crate::metrics::MEILISEARCH_DB_SIZE
+    .set(response.database_size as i64);
+
+    crate::metrics::MEILISEARCH_INDEX_COUNT
+    .set(response.indexes.len() as i64);
+
+    for (index, value) in response.indexes.iter() {
+        crate::metrics::MEILISEARCH_DOCS_COUNT
+        .with_label_values(&[&index])
+        .set(value.number_of_documents as i64);
+    }
+
+    let encoder = TextEncoder::new();
+    let mut buffer = vec![];
+    encoder
+        .encode(&prometheus::gather(), &mut buffer)
+        .expect("Failed to encode metrics");
+
+    let response = String::from_utf8(buffer.clone()).expect("Failed to convert bytes to string");
+    buffer.clear();
+
+    Ok(HttpResponse::Ok()
+        .insert_header(header::ContentType(mime::TEXT_PLAIN))
+        .body(response))
+}