Substitute HashMap for BtreeMap in family

benches/encoding/proto.rs

@@ -1,36 +1,40 @@
 // Benchmark inspired by
 // https://github.com/tikv/rust-prometheus/blob/ab1ca7285d3463504381a5025ae1951e020d6796/benches/text_encoder.rs:write
 
-use criterion::{black_box, criterion_group, criterion_main, Criterion};
-use prometheus_client::encoding::prometheus_protobuf;
-use prometheus_client::metrics::counter::Counter;
-use prometheus_client::metrics::family::Family;
-use prometheus_client::metrics::histogram::{exponential_buckets, Histogram};
-use prometheus_client::registry::Registry;
+use criterion::{Criterion, black_box, criterion_group, criterion_main};
+use prometheus_client::{
+    encoding::prometheus_protobuf,
+    metrics::{
+        counter::Counter,
+        family::Family,
+        histogram::{Histogram, exponential_buckets},
+    },
+    registry::Registry,
+};
 use prometheus_client_derive_encode::{EncodeLabelSet, EncodeLabelValue};
 
 pub fn proto(c: &mut Criterion) {
     c.bench_function("encode", |b| {
-        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug)]
+        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug, PartialOrd, Ord)]
         struct CounterLabels {
             path: String,
             method: Method,
             some_number: u64,
         }
 
-        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelValue, Debug)]
+        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelValue, Debug, PartialOrd, Ord)]
         enum Method {
             Get,
             #[allow(dead_code)]
             Put,
         }
 
-        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug)]
+        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug, PartialOrd, Ord)]
         struct HistogramLabels {
             region: Region,
         }
 
-        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelValue, Debug)]
+        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelValue, Debug, PartialOrd, Ord)]
         enum Region {
             Africa,
             #[allow(dead_code)]

benches/encoding/text.rs

@@ -10,21 +10,21 @@ use std::fmt::Write;
 
 pub fn text(c: &mut Criterion) {
     c.bench_function("encode", |b| {
-        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug)]
+        #[derive(Clone, Ord, PartialOrd, PartialEq, Eq, EncodeLabelSet, Debug)]
         struct Labels {
             method: Method,
             status: Status,
             some_number: u64,
         }
 
-        #[derive(Clone, Hash, PartialEq, Eq, EncodeLabelValue, Debug)]
+        #[derive(Clone, Ord, PartialOrd, PartialEq, Eq, EncodeLabelValue, Debug)]
         enum Method {
             Get,
             #[allow(dead_code)]
             Put,
         }
 
-        #[derive(Clone, Hash, PartialEq, Eq, Debug)]
+        #[derive(Clone, Ord, PartialOrd, PartialEq, Eq, Debug)]
         enum Status {
             Two,
             #[allow(dead_code)]

benches/family.rs

@@ -43,20 +43,20 @@ pub fn family(c: &mut Criterion) {
     });
 
     c.bench_function("counter family with custom type label set", |b| {
-        #[derive(Clone, Hash, PartialEq, Eq)]
+        #[derive(Clone, Ord, PartialOrd, PartialEq, Eq)]
         struct Labels {
             method: Method,
             status: Status,
         }
 
-        #[derive(Clone, Hash, PartialEq, Eq)]
+        #[derive(Clone, Ord, PartialOrd, PartialEq, Eq)]
         enum Method {
             Get,
             #[allow(dead_code)]
             Put,
         }
 
-        #[derive(Clone, Hash, PartialEq, Eq)]
+        #[derive(Clone, Ord, PartialOrd, PartialEq, Eq)]
         enum Status {
             Two,
             #[allow(dead_code)]

derive-encode/tests/lib.rs

@@ -1,18 +1,18 @@
 use std::sync::Arc;
 
-use prometheus_client::encoding::text::encode;
-use prometheus_client::encoding::{EncodeLabelSet, EncodeLabelValue};
-use prometheus_client::metrics::counter::Counter;
-use prometheus_client::metrics::family::Family;
-use prometheus_client::registry::Registry;
+use prometheus_client::{
+    encoding::{EncodeLabelSet, EncodeLabelValue, text::encode},
+    metrics::{counter::Counter, family::Family},
+    registry::Registry,
+};
 
-#[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug)]
+#[derive(Clone, Hash, PartialEq, Eq, EncodeLabelSet, Debug, PartialOrd, Ord)]
 struct Labels {
     method: Method,
     path: String,
 }
 
-#[derive(Clone, Hash, PartialEq, Eq, EncodeLabelValue, Debug)]
+#[derive(Clone, Hash, PartialEq, Eq, EncodeLabelValue, Debug, PartialOrd, Ord)]
 enum Method {
     Get,
     #[allow(dead_code)]
@@ -47,11 +47,11 @@ fn basic_flow() {
 
 mod protobuf {
     use crate::{Labels, Method};
-    use prometheus_client::encoding::prometheus_protobuf::encode;
-    use prometheus_client::encoding::prometheus_protobuf::prometheus_data_model;
-    use prometheus_client::metrics::counter::Counter;
-    use prometheus_client::metrics::family::Family;
-    use prometheus_client::registry::Registry;
+    use prometheus_client::{
+        encoding::prometheus_protobuf::{encode, prometheus_data_model},
+        metrics::{counter::Counter, family::Family},
+        registry::Registry,
+    };
 
     #[test]
     fn structs() {
@@ -106,7 +106,7 @@ mod protobuf {
 
 #[test]
 fn remap_keyword_identifiers() {
-    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug)]
+    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug, PartialOrd, Ord)]
     struct Labels {
         // `r#type` is problematic as `r#` is not a valid OpenMetrics label name
         // but one needs to use keyword identifier syntax (aka. raw identifiers)
@@ -137,7 +137,7 @@ fn remap_keyword_identifiers() {
 
 #[test]
 fn arc_string() {
-    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug)]
+    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug, PartialOrd, Ord)]
     struct Labels {
         client_id: Arc<String>,
     }
@@ -167,12 +167,12 @@ fn arc_string() {
 
 #[test]
 fn flatten() {
-    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug)]
+    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug, PartialOrd, Ord)]
     struct CommonLabels {
         a: u64,
         b: u64,
     }
-    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug)]
+    #[derive(EncodeLabelSet, Hash, Clone, Eq, PartialEq, Debug, PartialOrd, Ord)]
     struct Labels {
         unique: u64,
         #[prometheus(flatten)]

examples/actix-web.rs

@@ -8,13 +8,13 @@ use prometheus_client::metrics::counter::Counter;
 use prometheus_client::metrics::family::Family;
 use prometheus_client::registry::Registry;
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelValue)]
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, EncodeLabelValue)]
 pub enum Method {
     Get,
     Post,
 }
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelSet)]
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, EncodeLabelSet)]
 pub struct MethodLabels {
     pub method: Method,
 }

examples/axum.rs

@@ -13,13 +13,13 @@ use prometheus_client_derive_encode::{EncodeLabelSet, EncodeLabelValue};
 use std::sync::Arc;
 use tokio::sync::Mutex;
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelValue)]
+#[derive(Clone, Debug, Ord, PartialOrd, PartialEq, Eq, EncodeLabelValue)]
 pub enum Method {
     Get,
     Post,
 }
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelSet)]
+#[derive(Clone, Debug, Ord, PartialOrd, PartialEq, Eq, EncodeLabelSet)]
 pub struct MethodLabels {
     pub method: Method,
 }

examples/tide.rs

@@ -44,13 +44,13 @@ async fn main() -> std::result::Result<(), std::io::Error> {
     Ok(())
 }
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelSet)]
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, EncodeLabelSet)]
 struct Labels {
     method: Method,
     path: String,
 }
 
-#[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelValue)]
+#[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, EncodeLabelValue)]
 enum Method {
     Get,
     Put,

src/encoding/text.rs

@@ -37,16 +37,15 @@
 //! assert_eq!(expected_msg, buffer);
 //! ```
 
-use crate::encoding::{
-    EncodeExemplarTime, EncodeExemplarValue, EncodeLabelSet, NativeHistogram, NoLabelSet,
+use crate::{
+    encoding::{
+        EncodeExemplarTime, EncodeExemplarValue, EncodeLabelSet, NativeHistogram, NoLabelSet,
+    },
+    metrics::{MetricType, exemplar::Exemplar},
+    registry::{Prefix, Registry, Unit},
 };
-use crate::metrics::exemplar::Exemplar;
-use crate::metrics::MetricType;
-use crate::registry::{Prefix, Registry, Unit};
 
-use std::borrow::Cow;
-use std::collections::HashMap;
-use std::fmt::Write;
+use std::{borrow::Cow, collections::HashMap, fmt::Write};
 
 /// Encode both the metrics registered with the provided [`Registry`] and the
 /// EOF marker into the provided [`Write`]r using the OpenMetrics text format.
@@ -759,17 +758,21 @@ impl std::fmt::Write for LabelValueEncoder<'_> {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::metrics::exemplar::HistogramWithExemplars;
-    use crate::metrics::family::Family;
-    use crate::metrics::gauge::Gauge;
-    use crate::metrics::histogram::{exponential_buckets, Histogram, NativeHistogramConfig};
-    use crate::metrics::info::Info;
-    use crate::metrics::{counter::Counter, exemplar::CounterWithExemplar};
+    use crate::metrics::{
+        counter::Counter,
+        exemplar::{CounterWithExemplar, HistogramWithExemplars},
+        family::Family,
+        gauge::Gauge,
+        histogram::{Histogram, NativeHistogramConfig, exponential_buckets},
+        info::Info,
+    };
     use pyo3::{prelude::*, types::PyModule};
-    use std::borrow::Cow;
-    use std::fmt::Error;
-    use std::sync::atomic::{AtomicI32, AtomicU32};
-    use std::time::{SystemTime, UNIX_EPOCH};
+    use std::{
+        borrow::Cow,
+        fmt::Error,
+        sync::atomic::{AtomicI32, AtomicU32},
+        time::{SystemTime, UNIX_EPOCH},
+    };
 
     #[test]
     fn encode_counter() {
@@ -916,8 +919,7 @@ mod tests {
 
         encode(&mut encoded, &registry).unwrap();
 
-        let expected = "# HELP my_prefix_my_counter_family My counter family.\n"
-            .to_owned()
+        let expected = "# HELP my_prefix_my_counter_family My counter family.\n".to_owned()
             + "# TYPE my_prefix_my_counter_family counter\n"
             + "my_prefix_my_counter_family_total{my_key=\"my_value\",method=\"GET\",status=\"200\"} 1\n"
             + "# EOF\n";
@@ -1020,7 +1022,7 @@ mod tests {
             Family::new_with_constructor(|| Histogram::new(exponential_buckets(1.0, 2.0, 10)));
         registry.register("my_histogram", "My histogram", family.clone());
 
-        #[derive(Eq, PartialEq, Hash, Debug, Clone)]
+        #[derive(Eq, PartialEq, Ord, PartialOrd, Debug, Clone)]
         struct EmptyLabels {}
 
         impl EncodeLabelSet for EmptyLabels {
@@ -1210,7 +1212,7 @@ mod tests {
 
     #[test]
     fn label_sets_can_be_composed() {
-        #[derive(Clone, Debug, Eq, Hash, PartialEq)]
+        #[derive(Clone, Debug, Ord, PartialOrd, Eq, PartialEq)]
         struct Color(&'static str);
         impl EncodeLabelSet for Color {
             fn encode(
@@ -1225,7 +1227,7 @@ mod tests {
             }
         }
 
-        #[derive(Clone, Debug, Eq, Hash, PartialEq)]
+        #[derive(Clone, Debug, Ord, PartialOrd, Eq, PartialEq)]
         struct Size(&'static str);
         impl EncodeLabelSet for Size {
             fn encode(
@@ -1373,4 +1375,53 @@ def parse(input):
             + "# EOF\n";
         assert_eq!(expected, encoded);
     }
+
+    #[test]
+    fn metrics_are_sorted_by_registration_order() {
+        let mut registry = Registry::default();
+        let counter: Counter = Counter::default();
+        let another_counter: Counter = Counter::default();
+        registry.register("my_counter", "My counter", counter);
+        registry.register("another_counter", "Another counter", another_counter);
+
+        let mut encoded = String::new();
+        encode(&mut encoded, &registry).unwrap();
+
+        let expected = "# HELP my_counter My counter.\n".to_owned()
+            + "# TYPE my_counter counter\n"
+            + "my_counter_total 0\n"
+            + "# HELP another_counter Another counter.\n"
+            + "# TYPE another_counter counter\n"
+            + "another_counter_total 0\n"
+            + "# EOF\n";
+        assert_eq!(expected, encoded);
+    }
+
+    #[test]
+    fn metric_family_is_sorted_lexicographically() {
+        let mut registry = Registry::default();
+        let gauge = Family::<Vec<(String, String)>, Gauge>::default();
+        registry.register("my_gauge", "My gauge", gauge.clone());
+
+        gauge
+            .get_or_create(&vec![("label".to_string(), "0".to_string())])
+            .set(0);
+        gauge
+            .get_or_create(&vec![("label".to_string(), "2".to_string())])
+            .set(2);
+        gauge
+            .get_or_create(&vec![("label".to_string(), "1".to_string())])
+            .set(1);
+
+        let mut encoded = String::new();
+        encode(&mut encoded, &registry).unwrap();
+
+        let expected = "# HELP my_gauge My gauge.\n".to_owned()
+            + "# TYPE my_gauge gauge\n"
+            + "my_gauge{label=\"0\"} 0\n"
+            + "my_gauge{label=\"1\"} 1\n"
+            + "my_gauge{label=\"2\"} 2\n"
+            + "# EOF\n";
+        assert_eq!(expected, encoded);
+    }
 }

src/lib.rs

@@ -31,15 +31,15 @@
 //! //
 //! // You could as well use `(String, String)` to represent a label set,
 //! // instead of the custom type below.
-//! #[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelSet)]
+//! #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, EncodeLabelSet)]
 //! struct Labels {
 //!   // Use your own enum types to represent label values.
 //!   method: Method,
 //!   // Or just a plain string.
 //!   path: String,
 //! };
 //!
-//! #[derive(Clone, Debug, Hash, PartialEq, Eq, EncodeLabelValue)]
+//! #[derive(Clone, Debug, PartialEq, Eq, PartialOrd, Ord, EncodeLabelValue)]
 //! enum Method {
 //!   GET,
 //!   PUT,