Call scopeInfoMetrics only once even if it returns an error

CHANGELOG.md

@@ -30,6 +30,10 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - Removed the deprecated internal packages in `go.opentelemetry.io/otel/exporters/otlp` and its sub-packages. (#4469)
 - Dropped guaranteed support for versions of Go less than 1.20. (#4481)
 
+### Fixed
+
+- In `go.opentelemetry.op/otel/exporters/prometheus`, don't try to create the prometheus metric on every `Collect` if we know the scope is invalid. (#4499)
+
 ## [1.17.0/0.40.0/0.0.5] 2023-08-28
 
 ### Added

exporters/prometheus/exporter.go

@@ -87,6 +87,7 @@
 	disableTargetInfo bool
 	targetInfo        prometheus.Metric
 	scopeInfos        map[instrumentation.Scope]prometheus.Metric
+	scopeInfoErrs     map[instrumentation.Scope]error
 	metricFamilies    map[string]*dto.MetricFamily
 }
 
@@ -110,6 +111,7 @@
 		withoutCounterSuffixes: cfg.withoutCounterSuffixes,
 		disableScopeInfo:       cfg.disableScopeInfo,
 		scopeInfos:             make(map[instrumentation.Scope]prometheus.Metric),
+		scopeInfoErrs:          make(map[instrumentation.Scope]error),
 		metricFamilies:         make(map[string]*dto.MetricFamily),
 		namespace:              cfg.namespace,
 	}
@@ -469,8 +471,14 @@
 		return scopeInfo, nil
 	}
 
-	scopeInfo, err := createScopeInfoMetric(scope)
+	err, ok := c.scopeInfoErrs[scope]
+	if ok {
+		return nil, fmt.Errorf("cannot retrieve scope info metric: %w", err)
+	}
+
+	scopeInfo, err = createScopeInfoMetric(scope)
 	if err != nil {
+		c.scopeInfoErrs[scope] = err
 		return nil, fmt.Errorf("cannot create scope info metric: %w", err)
 	}