feat: add a field in config file to specify listen socket address for prometheus (#592)

Author: henil

rumqttd/CHANGELOG.md

@@ -8,10 +8,12 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Added
+- `PrometheusSetting` now takes `listen` to specify listener address instead of default `127.0.0.1`. Do not use `listen` and `port` together.
 
 ### Changed
 
 ### Deprecated
+- `PrometheusSetting`'s `port` will be removed in favour of `listen`.
 
 ### Removed
 

rumqttd/rumqttd.toml

@@ -79,7 +79,7 @@ next_connection_delay_ms = 1
     max_inflight_size = 1024
 
 [prometheus]
-port = 9042
+listen = "127.0.0.1:9042"
 interval = 1
 
 [ws]
@@ -91,4 +91,4 @@ listen = "0.0.0.0:3030"
 #     [metrics.alerts]
 #     push_interval = 1
 #     [metrics.meters]
-#     push_interval = 1
+#     push_interval = 1

rumqttd/src/lib.rs

@@ -54,7 +54,9 @@ pub struct Config {
 
 #[derive(Debug, Serialize, Deserialize, Clone)]
 pub struct PrometheusSetting {
-    port: u16,
+    #[deprecated(note = "Use listen instead")]
+    port: Option<u16>,
+    listen: Option<SocketAddr>,
     // How frequently to update metrics
     interval: u64,
 }
@@ -144,8 +146,7 @@ impl ConsoleSettings {
     }
 }
 
-#[derive(Debug, Serialize, Deserialize, Clone)]
-#[derive(Default)]
+#[derive(Debug, Serialize, Deserialize, Clone, Default)]
 pub enum Transport {
     #[serde(rename = "tcp")]
     #[default]
@@ -157,8 +158,6 @@ pub enum Transport {
     },
 }
 
-
-
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct ClientAuth {
     certs: PathBuf,

rumqttd/src/link/mod.rs

@@ -8,4 +8,3 @@ pub mod remote;
 #[cfg(feature = "websockets")]
 pub mod shadow;
 pub mod timer;
-

rumqttd/src/server/broker.rs

@@ -14,7 +14,7 @@ use crate::protocol::Protocol;
 use crate::server::tls::{self, TLSAcceptor};
 use crate::{meters, ConnectionSettings, Meter};
 use flume::{RecvError, SendError, Sender};
-use std::net::SocketAddr;
+use std::net::{IpAddr, Ipv4Addr, SocketAddr};
 use std::sync::Arc;
 use tracing::{error, field, info, Instrument};
 #[cfg(feature = "websockets")]
@@ -233,14 +233,24 @@ impl Broker {
         }
 
         if let Some(prometheus_setting) = &self.config.prometheus {
-            let port = prometheus_setting.port;
             let timeout = prometheus_setting.interval;
+            // If port is specified use it instead of listen.
+            // NOTE: This means listen is ignored when `port` is specified.
+            // `port` will be removed in future release in favour of `listen`
+            let addr = {
+                #[allow(deprecated)]
+                match prometheus_setting.port {
+                    Some(port) => SocketAddr::new("127.0.0.1".parse().unwrap(), port),
+                    None => prometheus_setting.listen.unwrap_or(SocketAddr::new(
+                        IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1)),
+                        9042,
+                    )),
+                }
+            };
             let metrics_thread = thread::Builder::new().name("Metrics".to_owned());
             let meter_link = self.meters().unwrap();
-
             metrics_thread.spawn(move || {
-                let builder = PrometheusBuilder::new()
-                    .with_http_listener(SocketAddr::new("127.0.0.1".parse().unwrap(), port));
+                let builder = PrometheusBuilder::new().with_http_listener(addr);
                 builder.install().unwrap();
 
                 let total_publishes = register_gauge!("metrics.router.total_publishes");