Added _total suffix to OTEL counter metrics. (jaegertracing#5810)

**Which problem is this PR solving?**

This PR addresses a part of the issue [jaegertracing#5633
](jaegertracing#5633)

**Description of the changes**
This is a PR to achieve Observability Parity in metrics between V1 and
V2 components by configuring OTEL Collector to emit desired metrics.
**How was this change tested?**

The changes were tested by running the following command:

```bash
make test
```
```bash
CI actions and compare.py script
```
**Checklist**

- [x] I have read
[CONTRIBUTING_GUIDELINES.md](https://github.com/jaegertracing/jaeger/blob/master/CONTRIBUTING_GUIDELINES.md)
- [x] I have signed all commits
- [x] I have added unit tests for the new functionality
- [x] I have run lint and test steps successfully
  - `for jaeger: make lint test`
  - `for jaeger-ui: yarn lint` and `yarn test`

---------

Signed-off-by: Wise-Wizard <[email protected]>
Signed-off-by: Jared Tan <[email protected]>

Author: Wise-Wizard

internal/metrics/otelmetrics/factory.go

@@ -32,7 +32,7 @@ func NewFactory(meterProvider metric.MeterProvider) metrics.Factory {
 }
 
 func (f *otelFactory) Counter(opts metrics.Options) metrics.Counter {
-	name := f.subScope(opts.Name)
+	name := CounterNamingConvention(f.subScope(opts.Name))
 	counter, err := f.meter.Int64Counter(name)
 	if err != nil {
 		log.Printf("Error creating OTEL counter: %v", err)
@@ -131,3 +131,10 @@ func attributeSetOption(tags map[string]string) metric.MeasurementOption {
 	}
 	return metric.WithAttributes(attributes...)
 }
+
+func CounterNamingConvention(name string) string {
+	if !strings.HasSuffix(name, "_total") {
+		name += "_total"
+	}
+	return name
+}

internal/metrics/otelmetrics/factory_test.go

@@ -104,6 +104,17 @@ func TestCounter(t *testing.T) {
 	assert.Equal(t, expectedLabels, promLabelsToMap(metrics[0].GetLabel()))
 }
 
+func TestCounterNamingConvention(t *testing.T) {
+	input := "test_counter"
+	expected := "test_counter_total"
+
+	result := otelmetrics.CounterNamingConvention(input)
+
+	if result != expected {
+		t.Errorf("Expected %s, but got %s", expected, result)
+	}
+}
+
 func TestGauge(t *testing.T) {
 	registry := promReg.NewPedanticRegistry()
 	factory := newTestFactory(t, registry)

scripts/compare_metrics.py

@@ -1,9 +1,3 @@
-# Run the following commands first to create the JSON files:
-# Run V1 Binary
-# prom2json http://localhost:14269/metrics > V1_Metrics.json
-# Run V2 Binary
-# prom2json http://localhost:8888/metrics > V2_Metrics.json
-
 import json
 
 v1_metrics_path = "./V1_Metrics.json"
@@ -41,7 +35,7 @@ def extract_metrics_with_labels(metrics, strip_prefix=None):
 for name, labels in v1_metrics_with_labels.items():
     if name in v2_metrics_with_labels:
         common_metrics[name] = labels
-    else:
+    elif not name.startswith("jaeger_agent"):
         v1_only_metrics[name] = labels
 
 for name, labels in v2_metrics_with_labels.items():
@@ -54,6 +48,7 @@ def extract_metrics_with_labels(metrics, strip_prefix=None):
     "v2_only_metrics": v2_only_metrics
 }
 
+# Write the differences to a new JSON file
 differences_path = "./differences.json"
 with open(differences_path, 'w') as file:
     json.dump(differences, file, indent=4)