refactor(metrics/identify): update to new collector trait

Updates to `prometheus-client` `Collector` trait refactor introduced with prometheus/client_rust#149.

Pull-Request: #4160.

Cargo.toml

@@ -98,7 +98,6 @@ libp2p-pnet = { version = "0.24.0", path = "transports/pnet" }
 libp2p-quic = { version = "0.10.0", path = "transports/quic" }
 libp2p-relay = { version = "0.17.0", path = "protocols/relay" }
 libp2p-rendezvous = { version = "0.14.0", path = "protocols/rendezvous" }
-libp2p-upnp = { version = "0.2.0", path = "protocols/upnp" }
 libp2p-request-response = { version = "0.26.0", path = "protocols/request-response" }
 libp2p-server = { version = "0.12.3", path = "misc/server" }
 libp2p-swarm = { version = "0.44.0", path = "swarm" }
@@ -107,19 +106,21 @@ libp2p-swarm-test = { version = "0.3.0", path = "swarm-test" }
 libp2p-tcp = { version = "0.41.0", path = "transports/tcp" }
 libp2p-tls = { version = "0.3.0", path = "transports/tls" }
 libp2p-uds = { version = "0.40.0", path = "transports/uds" }
+libp2p-upnp = { version = "0.2.0", path = "protocols/upnp" }
 libp2p-webrtc = { version = "0.6.1-alpha", path = "transports/webrtc" }
 libp2p-webrtc-utils = { version = "0.1.0", path = "misc/webrtc-utils" }
 libp2p-webrtc-websys = { version = "0.2.0-alpha", path = "transports/webrtc-websys" }
 libp2p-websocket = { version = "0.43.0", path = "transports/websocket" }
 libp2p-websocket-websys = { version = "0.3.0", path = "transports/websocket-websys" }
 libp2p-webtransport-websys = { version = "0.2.0", path = "transports/webtransport-websys" }
 libp2p-yamux = { version = "0.45.0", path = "muxers/yamux" }
+multiaddr = "0.18.0"
+multihash = "0.19.1"
 multistream-select = { version = "0.13.0", path = "misc/multistream-select" }
+prometheus-client = "0.22.0"
 quick-protobuf-codec = { version = "0.2.0", path = "misc/quick-protobuf-codec" }
 quickcheck = { package = "quickcheck-ext", path = "misc/quickcheck-ext" }
 rw-stream-sink = { version = "0.4.0", path = "misc/rw-stream-sink" }
-multiaddr = "0.18.0"
-multihash = "0.19.1"
 
 [patch.crates-io]
 

examples/metrics/Cargo.toml

@@ -15,7 +15,7 @@ hyper = { version = "0.14", features = ["server", "tcp", "http1"] }
 libp2p = { path = "../../libp2p", features = ["async-std", "metrics", "ping", "noise", "identify", "tcp", "yamux", "macros"] }
 log = "0.4.20"
 tokio = { version = "1", features = ["rt-multi-thread"] }
-prometheus-client = "0.21.2"
+prometheus-client = { workspace = true }
 
 [lints]
 workspace = true

misc/metrics/Cargo.toml

@@ -29,8 +29,7 @@ libp2p-kad = { workspace = true, optional = true }
 libp2p-ping = { workspace = true, optional = true }
 libp2p-relay =  { workspace = true, optional = true }
 libp2p-swarm = { workspace = true }
-once_cell = "1.18.0"
-prometheus-client = { version = "0.21.2"}
+prometheus-client = { workspace = true }
 
 [dev-dependencies]
 libp2p-identity = { workspace = true, features = ["rand"] }

misc/metrics/src/identify.rs

@@ -21,45 +21,15 @@
 use crate::protocol_stack;
 use libp2p_identity::PeerId;
 use libp2p_swarm::StreamProtocol;
-use once_cell::sync::Lazy;
 use prometheus_client::collector::Collector;
-use prometheus_client::encoding::EncodeLabelSet;
+use prometheus_client::encoding::{DescriptorEncoder, EncodeLabelSet, EncodeMetric};
 use prometheus_client::metrics::counter::Counter;
-use prometheus_client::metrics::family::ConstFamily;
 use prometheus_client::metrics::gauge::ConstGauge;
-use prometheus_client::registry::{Descriptor, LocalMetric, Registry};
-use prometheus_client::MaybeOwned;
-use std::borrow::Cow;
+use prometheus_client::metrics::MetricType;
+use prometheus_client::registry::Registry;
 use std::collections::HashMap;
 use std::sync::{Arc, Mutex};
 
-static PROTOCOLS_DESCRIPTOR: Lazy<Descriptor> = Lazy::new(|| {
-    Descriptor::new(
-        "remote_protocols",
-        "Number of connected nodes supporting a specific protocol, with \"unrecognized\" for each peer supporting one or more unrecognized protocols",
-        None,
-        None,
-        vec![],
-    )
-});
-static LISTEN_ADDRESSES_DESCRIPTOR: Lazy<Descriptor> = Lazy::new(|| {
-    Descriptor::new(
-        "remote_listen_addresses",
-        "Number of connected nodes advertising a specific listen address",
-        None,
-        None,
-        vec![],
-    )
-});
-static OBSERVED_ADDRESSES_DESCRIPTOR: Lazy<Descriptor> = Lazy::new(|| {
-    Descriptor::new(
-        "local_observed_addresses",
-        "Number of connected nodes observing the local node at a specific address",
-        None,
-        None,
-        vec![],
-    )
-});
 const ALLOWED_PROTOCOLS: &[StreamProtocol] = &[
     #[cfg(feature = "dcutr")]
     libp2p_dcutr::PROTOCOL_NAME,
@@ -187,10 +157,7 @@ impl Peers {
 }
 
 impl Collector for Peers {
-    fn collect<'a>(
-        &'a self,
-    ) -> Box<dyn Iterator<Item = (Cow<'a, Descriptor>, MaybeOwned<'a, Box<dyn LocalMetric>>)> + 'a>
-    {
+    fn encode(&self, mut encoder: DescriptorEncoder) -> Result<(), std::fmt::Error> {
         let mut count_by_protocols: HashMap<String, i64> = Default::default();
         let mut count_by_listen_addresses: HashMap<String, i64> = Default::default();
         let mut count_by_observed_addresses: HashMap<String, i64> = Default::default();
@@ -240,40 +207,49 @@ impl Collector for Peers {
             }
         }
 
-        let count_by_protocols: Box<dyn LocalMetric> =
-            Box::new(ConstFamily::new(count_by_protocols.into_iter().map(
-                |(protocol, count)| ([("protocol", protocol)], ConstGauge::new(count)),
-            )));
+        {
+            let mut family_encoder = encoder.encode_descriptor(
+                "remote_protocols",
+                "Number of connected nodes supporting a specific protocol, with \"unrecognized\" for each peer supporting one or more unrecognized protocols",
+                None,
+                MetricType::Gauge,
+            )?;
+            for (protocol, count) in count_by_protocols.into_iter() {
+                let labels = [("protocol", protocol)];
+                let metric_encoder = family_encoder.encode_family(&labels)?;
+                let metric = ConstGauge::new(count);
+                metric.encode(metric_encoder)?;
+            }
+        }
 
-        let count_by_listen_addresses: Box<dyn LocalMetric> =
-            Box::new(ConstFamily::new(count_by_listen_addresses.into_iter().map(
-                |(protocol, count)| ([("listen_address", protocol)], ConstGauge::new(count)),
-            )));
+        {
+            let mut family_encoder = encoder.encode_descriptor(
+                "remote_listen_addresses",
+                "Number of connected nodes advertising a specific listen address",
+                None,
+                MetricType::Gauge,
+            )?;
+            for (protocol, count) in count_by_listen_addresses.into_iter() {
+                let labels = [("listen_address", protocol)];
+                let metric_encoder = family_encoder.encode_family(&labels)?;
+                ConstGauge::new(count).encode(metric_encoder)?;
+            }
+        }
 
-        let count_by_observed_addresses: Box<dyn LocalMetric> = Box::new(ConstFamily::new(
-            count_by_observed_addresses
-                .into_iter()
-                .map(|(protocol, count)| {
-                    ([("observed_address", protocol)], ConstGauge::new(count))
-                }),
-        ));
+        {
+            let mut family_encoder = encoder.encode_descriptor(
+                "local_observed_addresses",
+                "Number of connected nodes observing the local node at a specific address",
+                None,
+                MetricType::Gauge,
+            )?;
+            for (protocol, count) in count_by_observed_addresses.into_iter() {
+                let labels = [("observed_address", protocol)];
+                let metric_encoder = family_encoder.encode_family(&labels)?;
+                ConstGauge::new(count).encode(metric_encoder)?;
+            }
+        }
 
-        Box::new(
-            [
-                (
-                    Cow::Borrowed(&*PROTOCOLS_DESCRIPTOR),
-                    MaybeOwned::Owned(count_by_protocols),
-                ),
-                (
-                    Cow::Borrowed(&*LISTEN_ADDRESSES_DESCRIPTOR),
-                    MaybeOwned::Owned(count_by_listen_addresses),
-                ),
-                (
-                    Cow::Borrowed(&*OBSERVED_ADDRESSES_DESCRIPTOR),
-                    MaybeOwned::Owned(count_by_observed_addresses),
-                ),
-            ]
-            .into_iter(),
-        )
+        Ok(())
     }
 }

misc/server/Cargo.toml

@@ -19,7 +19,7 @@ futures-timer = "3"
 hyper = { version = "0.14", features = ["server", "tcp", "http1"] }
 libp2p = { workspace = true, features = ["autonat", "dns", "tokio", "noise", "tcp", "yamux", "identify", "kad", "ping", "relay", "metrics", "rsa", "macros", "quic"] }
 log = "0.4"
-prometheus-client = "0.21.2"
+prometheus-client = { workspace = true }
 serde = "1.0.189"
 serde_derive = "1.0.125"
 serde_json = "1.0"

protocols/gossipsub/Cargo.toml

@@ -40,7 +40,7 @@ unsigned-varint = { version = "0.7.2", features = ["asynchronous_codec"] }
 void = "1.0.2"
 
 # Metrics dependencies
-prometheus-client = "0.21.2"
+prometheus-client = { workspace = true }
 
 [dev-dependencies]
 async-std = { version = "1.6.3", features = ["unstable"] }