fix: aligning the interceptor metrics vars with the OTEL spec

Signed-off-by: Joe Wogan <[email protected]>

Author: zorocloud

CHANGELOG.md

@@ -31,6 +31,7 @@ This changelog keeps track of work items that have been completed and are ready
 
 ### Fixes
 
+- **General**: Align the interceptor metrics env var configuration with the OTEL spec ([#1031](https://github.com/kedacore/http-add-on/issues/1031))
 - **General**: TODO ([#TODO](https://github.com/kedacore/http-add-on/issues/TODO))
 
 ### Deprecations

config/interceptor/e2e-test/otel/deployment.yaml

@@ -9,15 +9,15 @@ spec:
       containers:
       - name: interceptor
         env:
-        - name: KEDA_HTTP_OTEL_PROM_EXPORTER_ENABLED
+        - name: OTEL_PROM_EXPORTER_ENABLED
           value: "true"
-        - name: KEDA_HTTP_OTEL_PROM_EXPORTER_PORT
+        - name: OTEL_PROM_EXPORTER_PORT
           value: "2223"
-        - name: KEDA_HTTP_OTEL_HTTP_EXPORTER_ENABLED
+        - name: OTEL_EXPORTER_OTLP_METRICS_ENABLED
           value: "true"
-        - name: KEDA_HTTP_OTEL_HTTP_COLLECTOR_ENDPOINT
+        - name: OTEL_EXPORTER_OTLP_METRICS_ENDPOINT
           value: "opentelemetry-collector.open-telemetry-system:4318"
-        - name: KEDA_HTTP_OTEL_HTTP_COLLECTOR_INSECURE
+        - name: OTEL_EXPORTER_OTLP_METRICS_INSECURE
           value: "true"
-        - name: KEDA_HTTP_OTEL_METRIC_EXPORT_INTERVAL
+        - name: OTEL_EXPORTER_OTLP_METRICS_EXPORT_INTERVAL
           value: "1"

docs/operate.md

@@ -9,16 +9,16 @@ There are currently 2 supported methods for exposing metrics from the intercepto
 ### Configuring the Prometheus compatible metrics endpoint
 When configured, the interceptor proxy can expose metrics on a Prometheus compatible endpoint.
 
-This endpoint can be enabled by setting the `KEDA_HTTP_OTEL_PROM_EXPORTER_ENABLED` environment variable to `true` on the interceptor deployment (`true` by default) and by setting `KEDA_HTTP_OTEL_PROM_EXPORTER_PORT` to an unused port for the endpoint to be made avaialble on (`2223` by default).
+This endpoint can be enabled by setting the `OTEL_PROM_EXPORTER_ENABLED` environment variable to `true` on the interceptor deployment (`true` by default) and by setting `OTEL_PROM_EXPORTER_PORT` to an unused port for the endpoint to be made avaialble on (`2223` by default).
 
 ### Configuring the OTEL HTTP exporter
 When configured, the interceptor proxy can export metrics to a OTEL HTTP collector.
 
-The OTEL exporter can be enabled by setting the `KEDA_HTTP_OTEL_HTTP_EXPORTER_ENABLED` environment variable to `true` on the interceptor deployment (`false` by default). When enabled the `KEDA_HTTP_OTEL_HTTP_COLLECTOR_ENDPOINT` environment variable must also be configured so the exporter knows what collector to send the metrics to (e.g. opentelemetry-collector.open-telemetry-system:4318).
+The OTEL exporter can be enabled by setting the `OTEL_EXPORTER_OTLP_METRICS_ENABLED` environment variable to `true` on the interceptor deployment (`false` by default). When enabled the `OTEL_EXPORTER_OTLP_METRICS_ENDPOINT` environment variable must also be configured so the exporter knows what collector to send the metrics to (e.g. opentelemetry-collector.open-telemetry-system:4318).
 
-If the collector is exposed on a unsecured endpoint then you can set the `KEDA_HTTP_OTEL_HTTP_COLLECTOR_INSECURE` environment variable to `true` (`false` by default) which will disable client security on the exporter.
+If the collector is exposed on a unsecured endpoint then you can set the `OTEL_EXPORTER_OTLP_METRICS_INSECURE` environment variable to `true` (`false` by default) which will disable client security on the exporter.
 
-If you need to provide any headers such as authentication details in order to utilise your OTEL collector you can add them into the `KEDA_HTTP_OTEL_HTTP_HEADERS` environment variable. The frequency at which the metrics are exported can be configured by setting `KEDA_HTTP_OTEL_METRIC_EXPORT_INTERVAL` to the number of seconds you require between each export interval (`30` by default).
+If you need to provide any headers such as authentication details in order to utilise your OTEL collector you can add them into the `OTEL_EXPORTER_OTLP_METRICS_HEADERS` environment variable. The frequency at which the metrics are exported can be configured by setting `OTEL_EXPORTER_OTLP_METRICS_EXPORT_INTERVAL` to the number of seconds you require between each export interval (`30` by default).
 
 # Configuring TLS for the KEDA HTTP Add-on interceptor proxy
 

interceptor/config/metrics.go

@@ -7,19 +7,19 @@ import (
 // Metrics is the configuration for configuring metrics in the interceptor.
 type Metrics struct {
 	// Sets whether or not to enable the Prometheus metrics exporter
-	OtelPrometheusExporterEnabled bool `envconfig:"KEDA_HTTP_OTEL_PROM_EXPORTER_ENABLED" default:"true"`
+	OtelPrometheusExporterEnabled bool `envconfig:"OTEL_PROM_EXPORTER_ENABLED" default:"true"`
 	// Sets the port which the Prometheus compatible metrics endpoint should be served on
-	OtelPrometheusExporterPort int `envconfig:"KEDA_HTTP_OTEL_PROM_EXPORTER_PORT" default:"2223"`
+	OtelPrometheusExporterPort int `envconfig:"OTEL_PROM_EXPORTER_PORT" default:"2223"`
 	// Sets whether or not to enable the OTEL metrics exporter
-	OtelHTTPExporterEnabled bool `envconfig:"KEDA_HTTP_OTEL_HTTP_EXPORTER_ENABLED" default:"false"`
+	OtelHTTPExporterEnabled bool `envconfig:"OTEL_EXPORTER_OTLP_METRICS_ENABLED" default:"false"`
 	// Sets the HTTP endpoint where metrics should be sent to
-	OtelHTTPCollectorEndpoint string `envconfig:"KEDA_HTTP_OTEL_HTTP_COLLECTOR_ENDPOINT" default:"localhost:4318"`
+	OtelHTTPCollectorEndpoint string `envconfig:"OTEL_EXPORTER_OTLP_METRICS_ENDPOINT" default:"localhost:4318"`
 	// Sets the OTLP headers required by the otel exporter
-	OtelHTTPHeaders string `envconfig:"KEDA_HTTP_OTEL_HTTP_HEADERS" default:""`
+	OtelHTTPHeaders string `envconfig:"OTEL_EXPORTER_OTLP_METRICS_HEADERS" default:""`
 	// Set the connection to the otel HTTP collector endpoint to use HTTP rather than HTTPS
-	OtelHTTPCollectorInsecure bool `envconfig:"KEDA_HTTP_OTEL_HTTP_COLLECTOR_INSECURE" default:"false"`
+	OtelHTTPCollectorInsecure bool `envconfig:"OTEL_EXPORTER_OTLP_METRICS_INSECURE" default:"false"`
 	// Set the interval in seconds to export otel metrics to the configured collector endpoint
-	OtelMetricExportInterval int `envconfig:"KEDA_HTTP_OTEL_METRIC_EXPORT_INTERVAL" default:"30"`
+	OtelMetricExportInterval int `envconfig:"OTEL_EXPORTER_OTLP_METRICS_EXPORT_INTERVAL" default:"30"`
 }
 
 // Parse parses standard configs using envconfig and returns a pointer to the

interceptor/metrics/otelmetrics.go

@@ -30,12 +30,13 @@ func NewOtelMetrics(metricsConfig *config.Metrics, options ...metric.Option) *Ot
 	endpoint := otlpmetrichttp.WithEndpoint(metricsConfig.OtelHTTPCollectorEndpoint)
 	headersFromEnvVar := getHeaders(metricsConfig.OtelHTTPHeaders)
 	headers := otlpmetrichttp.WithHeaders(headersFromEnvVar)
+	path := otlpmetrichttp.WithURLPath("/v1/metrics")
 
 	if metricsConfig.OtelHTTPCollectorInsecure {
 		insecure := otlpmetrichttp.WithInsecure()
-		exporter, err = otlpmetrichttp.New(ctx, endpoint, headers, insecure)
+		exporter, err = otlpmetrichttp.New(ctx, endpoint, headers, path, insecure)
 	} else {
-		exporter, err = otlpmetrichttp.New(ctx, endpoint, headers)
+		exporter, err = otlpmetrichttp.New(ctx, endpoint, headers, path)
 	}
 
 	if err != nil {

tests/checks/interceptor_otel_metrics/interceptor_otel_metrics_test.go

@@ -171,7 +171,7 @@ func TestMetricGeneration(t *testing.T) {
 	// If the metric is not found first time around then retry with a delay.
 	if !ok {
 		// Add a small sleep to allow metrics to be pushed from the exporter to the collector
-		time.Sleep(5 * time.Second)
+		time.Sleep(10 * time.Second)
 		// Fetch metrics and validate them
 		family := fetchAndParsePrometheusMetrics(t, fmt.Sprintf("curl --insecure %s", otelCollectorPromURL))
 		val, ok = family["interceptor_request_count_total"]