chore: Upgrade prometheus to 0.14 and clean up protobuf-related code in lib.rs (#2920)

Co-authored-by: Cijo Thomas <[email protected]>

Author: houseme

opentelemetry-prometheus/CHANGELOG.md

@@ -2,6 +2,13 @@
 
 ## vNext
 
+## 0.29.1
+
+Released 2025-April-11
+
+- Update `prometheus` dependency version to 0.14
+- Remove `protobuf` dependency
+
 ## v0.29.0
 
 - Update `opentelemetry` dependency version to 0.29

opentelemetry-prometheus/Cargo.toml

@@ -23,8 +23,7 @@ rustdoc-args = ["--cfg", "docsrs"]
 once_cell = { version = "1.13" }
 opentelemetry = { version = "0.29", default-features = false, features = ["metrics"] }
 opentelemetry_sdk = { version = "0.29", default-features = false, features = ["metrics"] }
-prometheus = "0.13"
-protobuf = "2.14"
+prometheus = "0.14"
 tracing = { version = ">=0.1.40", default-features = false, optional = true } # optional for opentelemetry internal logging
 
 [dev-dependencies]

opentelemetry-prometheus/src/lib.rs

@@ -439,13 +439,13 @@ fn validate_metrics(
             );
             return (true, None);
         }
-        if existing.get_help() != description {
+        if existing.help() != description {
             otel_warn!(
                 name: "MetricValidationFailed",
                 message = "Instrument description conflict, using existing",
-                metric_description = format!("Instrument {name}, Existing: {:?}, dropped: {:?}", existing.get_help().to_string(), description.to_string()).as_str(),
+                metric_description = format!("Instrument {name}, Existing: {:?}, dropped: {:?}", existing.help().to_string(), description.to_string()).as_str(),
             );
-            return (false, Some(existing.get_help().to_string()));
+            return (false, Some(existing.help().to_string()));
         }
         (false, None)
     } else {
@@ -491,16 +491,16 @@ fn add_histogram_metric<T: Numeric>(
         let mut h = prometheus::proto::Histogram::default();
         h.set_sample_sum(dp.sum.as_f64());
         h.set_sample_count(dp.count);
-        h.set_bucket(protobuf::RepeatedField::from_vec(bucket));
+        h.set_bucket(bucket);
         let mut pm = prometheus::proto::Metric::default();
-        pm.set_label(protobuf::RepeatedField::from_vec(kvs));
+        pm.set_label(kvs);
         pm.set_histogram(h);
 
         let mut mf = prometheus::proto::MetricFamily::default();
         mf.set_name(name.to_string());
         mf.set_help(description.clone());
         mf.set_field_type(prometheus::proto::MetricType::HISTOGRAM);
-        mf.set_metric(protobuf::RepeatedField::from_vec(vec![pm]));
+        mf.set_metric(vec![pm]);
         res.push(mf);
     }
 }
@@ -525,7 +525,7 @@ fn add_sum_metric<T: Numeric>(
         );
 
         let mut pm = prometheus::proto::Metric::default();
-        pm.set_label(protobuf::RepeatedField::from_vec(kvs));
+        pm.set_label(kvs);
 
         if sum.is_monotonic {
             let mut c = prometheus::proto::Counter::default();
@@ -541,7 +541,7 @@ fn add_sum_metric<T: Numeric>(
         mf.set_name(name.to_string());
         mf.set_help(description.clone());
         mf.set_field_type(metric_type);
-        mf.set_metric(protobuf::RepeatedField::from_vec(vec![pm]));
+        mf.set_metric(vec![pm]);
         res.push(mf);
     }
 }
@@ -562,14 +562,14 @@ fn add_gauge_metric<T: Numeric>(
         let mut g = prometheus::proto::Gauge::default();
         g.set_value(dp.value.as_f64());
         let mut pm = prometheus::proto::Metric::default();
-        pm.set_label(protobuf::RepeatedField::from_vec(kvs));
+        pm.set_label(kvs);
         pm.set_gauge(g);
 
         let mut mf = prometheus::proto::MetricFamily::default();
         mf.set_name(name.to_string());
         mf.set_help(description.to_string());
         mf.set_field_type(MetricType::GAUGE);
-        mf.set_metric(protobuf::RepeatedField::from_vec(vec![pm]));
+        mf.set_metric(vec![pm]);
         res.push(mf);
     }
 }
@@ -583,17 +583,17 @@ fn create_info_metric(
     g.set_value(1.0);
 
     let mut m = prometheus::proto::Metric::default();
-    m.set_label(protobuf::RepeatedField::from_vec(get_attrs(
+    m.set_label(get_attrs(
         &mut resource.iter(),
         &[],
-    )));
+    ));
     m.set_gauge(g);
 
     let mut mf = MetricFamily::default();
     mf.set_name(target_info_name.into());
     mf.set_help(target_info_description.into());
     mf.set_field_type(MetricType::GAUGE);
-    mf.set_metric(protobuf::RepeatedField::from_vec(vec![m]));
+    mf.set_metric(vec![m]);
     mf
 }
 
@@ -614,14 +614,14 @@ fn create_scope_info_metric(scope: &InstrumentationScope) -> MetricFamily {
     }
 
     let mut m = prometheus::proto::Metric::default();
-    m.set_label(protobuf::RepeatedField::from_vec(labels));
+    m.set_label(labels);
     m.set_gauge(g);
 
     let mut mf = MetricFamily::default();
     mf.set_name(SCOPE_INFO_METRIC_NAME.into());
     mf.set_help(SCOPE_INFO_DESCRIPTION.into());
     mf.set_field_type(MetricType::GAUGE);
-    mf.set_metric(protobuf::RepeatedField::from_vec(vec![m]));
+    mf.set_metric(vec![m]);
     mf
 }