feat(metrics): support Gauge<u32, AtomicU32> type

CHANGELOG.md

@@ -4,6 +4,15 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.22.2]
+
+### Added
+
+- Added `Gauge<u32, AtomicU32>` implementation.
+  See [PR 191].
+
+[PR 191]: https://github.com/prometheus/client_rust/pull/191
+
 ## [0.22.1]
 
 ### Added

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "prometheus-client"
-version = "0.22.1"
+version = "0.22.2"
 authors = ["Max Inden <[email protected]>"]
 edition = "2021"
 description = "Open Metrics client library allowing users to natively instrument applications."

src/encoding.rs

@@ -544,6 +544,12 @@ pub trait EncodeGaugeValue {
     fn encode(&self, encoder: &mut GaugeValueEncoder) -> Result<(), std::fmt::Error>;
 }
 
+impl EncodeGaugeValue for u32 {
+    fn encode(&self, encoder: &mut GaugeValueEncoder) -> Result<(), std::fmt::Error> {
+        encoder.encode_u32(*self)
+    }
+}
+
 impl EncodeGaugeValue for i64 {
     fn encode(&self, encoder: &mut GaugeValueEncoder) -> Result<(), std::fmt::Error> {
         encoder.encode_i64(*self)
@@ -568,13 +574,17 @@ enum GaugeValueEncoderInner<'a> {
 }
 
 impl<'a> GaugeValueEncoder<'a> {
-    fn encode_f64(&mut self, v: f64) -> Result<(), std::fmt::Error> {
-        for_both_mut!(self, GaugeValueEncoderInner, e, e.encode_f64(v))
+    fn encode_u32(&mut self, v: u32) -> Result<(), std::fmt::Error> {
+        for_both_mut!(self, GaugeValueEncoderInner, e, e.encode_u32(v))
     }
 
     fn encode_i64(&mut self, v: i64) -> Result<(), std::fmt::Error> {
         for_both_mut!(self, GaugeValueEncoderInner, e, e.encode_i64(v))
     }
+
+    fn encode_f64(&mut self, v: f64) -> Result<(), std::fmt::Error> {
+        for_both_mut!(self, GaugeValueEncoderInner, e, e.encode_f64(v))
+    }
 }
 
 impl<'a> From<text::GaugeValueEncoder<'a>> for GaugeValueEncoder<'a> {

src/encoding/protobuf.rs

@@ -323,6 +323,10 @@ pub(crate) struct GaugeValueEncoder<'a> {
 }
 
 impl<'a> GaugeValueEncoder<'a> {
+    pub fn encode_u32(&mut self, v: u32) -> Result<(), std::fmt::Error> {
+        self.encode_i64(v as i64)
+    }
+
     pub fn encode_i64(&mut self, v: i64) -> Result<(), std::fmt::Error> {
         *self.value = openmetrics_data_model::gauge_value::Value::IntValue(v);
         Ok(())

src/encoding/text.rs

@@ -423,9 +423,9 @@ impl<'a> std::fmt::Debug for GaugeValueEncoder<'a> {
 }
 
 impl<'a> GaugeValueEncoder<'a> {
-    pub fn encode_f64(&mut self, v: f64) -> Result<(), std::fmt::Error> {
+    pub fn encode_u32(&mut self, v: u32) -> Result<(), std::fmt::Error> {
         self.writer.write_str(" ")?;
-        self.writer.write_str(dtoa::Buffer::new().format(v))?;
+        self.writer.write_str(itoa::Buffer::new().format(v))?;
         Ok(())
     }
 
@@ -434,6 +434,12 @@ impl<'a> GaugeValueEncoder<'a> {
         self.writer.write_str(itoa::Buffer::new().format(v))?;
         Ok(())
     }
+
+    pub fn encode_f64(&mut self, v: f64) -> Result<(), std::fmt::Error> {
+        self.writer.write_str(" ")?;
+        self.writer.write_str(dtoa::Buffer::new().format(v))?;
+        Ok(())
+    }
 }
 
 pub(crate) struct ExemplarValueEncoder<'a> {
@@ -565,6 +571,7 @@ mod tests {
     use crate::metrics::{counter::Counter, exemplar::CounterWithExemplar};
     use pyo3::{prelude::*, types::PyModule};
     use std::borrow::Cow;
+    use std::sync::atomic::AtomicU32;
 
     #[test]
     fn encode_counter() {
@@ -632,6 +639,8 @@ mod tests {
         let mut registry = Registry::default();
         let gauge: Gauge = Gauge::default();
         registry.register("my_gauge", "My gauge", gauge);
+        let gauge = Gauge::<u32, AtomicU32>::default();
+        registry.register("u32_gauge", "Gauge::<u32, AtomicU32>", gauge);
 
         let mut encoded = String::new();
 

src/metrics/gauge.rs

@@ -6,7 +6,7 @@ use crate::encoding::{EncodeGaugeValue, EncodeMetric, MetricEncoder};
 
 use super::{MetricType, TypedMetric};
 use std::marker::PhantomData;
-use std::sync::atomic::{AtomicI32, Ordering};
+use std::sync::atomic::{AtomicI32, AtomicU32, Ordering};
 #[cfg(not(any(target_arch = "mips", target_arch = "powerpc")))]
 use std::sync::atomic::{AtomicI64, AtomicU64};
 use std::sync::Arc;
@@ -134,55 +134,81 @@ pub trait Atomic<N> {
     fn get(&self) -> N;
 }
 
-#[cfg(not(any(target_arch = "mips", target_arch = "powerpc")))]
-impl Atomic<i64> for AtomicI64 {
-    fn inc(&self) -> i64 {
+impl Atomic<i32> for AtomicI32 {
+    fn inc(&self) -> i32 {
         self.inc_by(1)
     }
 
-    fn inc_by(&self, v: i64) -> i64 {
+    fn inc_by(&self, v: i32) -> i32 {
         self.fetch_add(v, Ordering::Relaxed)
     }
 
-    fn dec(&self) -> i64 {
+    fn dec(&self) -> i32 {
         self.dec_by(1)
     }
 
-    fn dec_by(&self, v: i64) -> i64 {
+    fn dec_by(&self, v: i32) -> i32 {
         self.fetch_sub(v, Ordering::Relaxed)
     }
 
-    fn set(&self, v: i64) -> i64 {
+    fn set(&self, v: i32) -> i32 {
         self.swap(v, Ordering::Relaxed)
     }
 
-    fn get(&self) -> i64 {
+    fn get(&self) -> i32 {
         self.load(Ordering::Relaxed)
     }
 }
 
-impl Atomic<i32> for AtomicI32 {
-    fn inc(&self) -> i32 {
+impl Atomic<u32> for AtomicU32 {
+    fn inc(&self) -> u32 {
         self.inc_by(1)
     }
 
-    fn inc_by(&self, v: i32) -> i32 {
+    fn inc_by(&self, v: u32) -> u32 {
         self.fetch_add(v, Ordering::Relaxed)
     }
 
-    fn dec(&self) -> i32 {
+    fn dec(&self) -> u32 {
         self.dec_by(1)
     }
 
-    fn dec_by(&self, v: i32) -> i32 {
+    fn dec_by(&self, v: u32) -> u32 {
         self.fetch_sub(v, Ordering::Relaxed)
     }
 
-    fn set(&self, v: i32) -> i32 {
+    fn set(&self, v: u32) -> u32 {
         self.swap(v, Ordering::Relaxed)
     }
 
-    fn get(&self) -> i32 {
+    fn get(&self) -> u32 {
+        self.load(Ordering::Relaxed)
+    }
+}
+
+#[cfg(not(any(target_arch = "mips", target_arch = "powerpc")))]
+impl Atomic<i64> for AtomicI64 {
+    fn inc(&self) -> i64 {
+        self.inc_by(1)
+    }
+
+    fn inc_by(&self, v: i64) -> i64 {
+        self.fetch_add(v, Ordering::Relaxed)
+    }
+
+    fn dec(&self) -> i64 {
+        self.dec_by(1)
+    }
+
+    fn dec_by(&self, v: i64) -> i64 {
+        self.fetch_sub(v, Ordering::Relaxed)
+    }
+
+    fn set(&self, v: i64) -> i64 {
+        self.swap(v, Ordering::Relaxed)
+    }
+
+    fn get(&self) -> i64 {
         self.load(Ordering::Relaxed)
     }
 }