[service] add internal factory method for meter provider

This will be used when moving the meter provider configuration to use the otel-go config package.

Part of open-telemetry#10414

Signed-off-by: Alex Boten <[email protected]>

service/telemetry/internal/factory.go

@@ -6,6 +6,8 @@ package internal // import "go.opentelemetry.io/collector/service/telemetry/inte
 import (
 	"context"
 
+	"go.opentelemetry.io/otel/metric"
+	metricnoop "go.opentelemetry.io/otel/metric/noop"
 	"go.opentelemetry.io/otel/trace"
 	tracenoop "go.opentelemetry.io/otel/trace/noop"
 	"go.uber.org/zap"
@@ -34,7 +36,8 @@ type Factory interface {
 	// CreateTracerProvider creates a TracerProvider.
 	CreateTracerProvider(ctx context.Context, set CreateSettings, cfg component.Config) (trace.TracerProvider, error)
 
-	// TODO: Add CreateMeterProvider.
+	// CreateMeterProvider creates a MeterProvider.
+	CreateMeterProvider(ctx context.Context, set CreateSettings, cfg component.Config) (metric.MeterProvider, error)
 
 	// unexportedFactoryFunc is used to prevent external implementations of Factory.
 	unexportedFactoryFunc()
@@ -62,6 +65,7 @@ type factory struct {
 	createDefaultConfig component.CreateDefaultConfigFunc
 	CreateLoggerFunc
 	CreateTracerProviderFunc
+	CreateMeterProviderFunc
 }
 
 func (f *factory) CreateDefaultConfig() component.Config {
@@ -102,6 +106,21 @@ func (f *factory) CreateTracerProvider(ctx context.Context, set CreateSettings,
 	return f.CreateTracerProviderFunc(ctx, set, cfg)
 }
 
+type CreateMeterProviderFunc func(context.Context, CreateSettings, component.Config) (metric.MeterProvider, error)
+
+func WithMeterProvier(createMeterProvider CreateMeterProviderFunc) FactoryOption {
+	return factoryOptionFunc(func(o *factory) {
+		o.CreateMeterProviderFunc = createMeterProvider
+	})
+}
+
+func (f *factory) CreateMeterProvider(ctx context.Context, set CreateSettings, cfg component.Config) (metric.MeterProvider, error) {
+	if f.CreateMeterProviderFunc == nil {
+		return metricnoop.NewMeterProvider(), nil
+	}
+	return f.CreateMeterProviderFunc(ctx, set, cfg)
+}
+
 func (f *factory) unexportedFactoryFunc() {}
 
 // NewFactory returns a new Factory.