feat: disable prometheus protobuf (#2578)

Co-authored-by: kodiakhq[bot] <49736102+kodiakhq[bot]@users.noreply.github.com>

Cargo.lock

@@ -3189,7 +3189,6 @@ dependencies = [
  "lazy_static",
  "memchr",
  "parking_lot",
- "protobuf",
  "thiserror",
 ]
 
@@ -3244,12 +3243,6 @@ dependencies = [
  "prost",
 ]
 
-[[package]]
-name = "protobuf"
-version = "2.25.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "23129d50f2c9355ced935fce8a08bd706ee2e7ce2b3b33bf61dace0e379ac63a"
-
 [[package]]
 name = "query"
 version = "0.1.0"

metric_exporters/Cargo.toml

@@ -8,7 +8,7 @@ edition = "2018"
 
 observability_deps = { path = "../observability_deps" }
 metric = { path = "../metric" }
-prometheus = "0.12"
+prometheus = { version = "0.12", default-features = false }
 
 [dev-dependencies] # In alphabetical order
 test_helpers = { path = "../test_helpers" }

metric_exporters/src/lib.rs

@@ -69,7 +69,7 @@ impl<'a, W: Write> metric::Reporter for PrometheusTextEncoder<'a, W> {
             }
         };
 
-        let mut metric = MetricFamily::new();
+        let mut metric = MetricFamily::default();
         metric.set_name(name);
         metric.set_help(description.to_string());
         metric.set_field_type(metric_type);
@@ -82,44 +82,52 @@ impl<'a, W: Write> metric::Reporter for PrometheusTextEncoder<'a, W> {
 
         let metrics = metrics.mut_metric();
 
-        let mut metric = Metric::new();
+        let mut metric = Metric::default();
 
-        for (name, value) in attributes.iter() {
-            let mut pair = LabelPair::new();
+        metric.set_label(
+            attributes
+                .iter()
+                .map(|(name, value)| {
+                    let mut pair = LabelPair::default();
                     pair.set_name(name.to_string());
                     pair.set_value(value.to_string());
-            metric.mut_label().push(pair)
-        }
+                    pair
+                })
+                .collect(),
+        );
 
         match observation {
             Observation::U64Counter(v) => {
-                let mut counter = Counter::new();
+                let mut counter = Counter::default();
                 counter.set_value(v as f64);
                 metric.set_counter(counter)
             }
             Observation::U64Gauge(v) => {
-                let mut gauge = Gauge::new();
+                let mut gauge = Gauge::default();
                 gauge.set_value(v as f64);
                 metric.set_gauge(gauge)
             }
             Observation::DurationCounter(v) => {
-                let mut counter = Counter::new();
+                let mut counter = Counter::default();
                 counter.set_value(v.as_secs_f64());
                 metric.set_counter(counter)
             }
             Observation::DurationGauge(v) => {
-                let mut gauge = Gauge::new();
+                let mut gauge = Gauge::default();
                 gauge.set_value(v.as_secs_f64());
                 metric.set_gauge(gauge)
             }
             Observation::U64Histogram(v) => {
-                let mut histogram = Histogram::new();
+                let mut histogram = Histogram::default();
                 let mut cumulative_count = 0;
 
-                for observation in v.buckets {
+                histogram.set_bucket(
+                    v.buckets
+                        .into_iter()
+                        .map(|observation| {
                             cumulative_count += observation.count;
 
-                    let mut bucket = Bucket::new();
+                            let mut bucket = Bucket::default();
                             let le = match observation.le {
                                 u64::MAX => f64::INFINITY,
                                 v => v as f64,
@@ -127,21 +135,26 @@ impl<'a, W: Write> metric::Reporter for PrometheusTextEncoder<'a, W> {
 
                             bucket.set_upper_bound(le);
                             bucket.set_cumulative_count(cumulative_count);
-                    histogram.mut_bucket().push(bucket)
-                }
+                            bucket
+                        })
+                        .collect(),
+                );
 
                 histogram.set_sample_count(cumulative_count);
                 histogram.set_sample_sum(v.total as f64);
                 metric.set_histogram(histogram)
             }
             Observation::DurationHistogram(v) => {
-                let mut histogram = Histogram::new();
+                let mut histogram = Histogram::default();
                 let mut cumulative_count = 0;
 
-                for observation in v.buckets {
+                histogram.set_bucket(
+                    v.buckets
+                        .into_iter()
+                        .map(|observation| {
                             cumulative_count += observation.count;
 
-                    let mut bucket = Bucket::new();
+                            let mut bucket = Bucket::default();
                             let le = match observation.le {
                                 metric::DURATION_MAX => f64::INFINITY,
                                 v => v.as_secs_f64(),
@@ -149,8 +162,10 @@ impl<'a, W: Write> metric::Reporter for PrometheusTextEncoder<'a, W> {
 
                             bucket.set_upper_bound(le);
                             bucket.set_cumulative_count(cumulative_count);
-                    histogram.mut_bucket().push(bucket)
-                }
+                            bucket
+                        })
+                        .collect(),
+                );
 
                 histogram.set_sample_count(cumulative_count);
                 histogram.set_sample_sum(v.total.as_secs_f64());