feat: initial tracing support (#1623)

vendor/go.opentelemetry.io/otel/metric/config.go

@@ -0,0 +1,69 @@
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package metric // import "go.opentelemetry.io/otel/metric"
+
+// MeterConfig contains options for Meters.
+type MeterConfig struct {
+	instrumentationVersion string
+	schemaURL              string
+}
+
+// InstrumentationVersion is the version of the library providing instrumentation.
+func (cfg MeterConfig) InstrumentationVersion() string {
+	return cfg.instrumentationVersion
+}
+
+// SchemaURL is the schema_url of the library providing instrumentation.
+func (cfg MeterConfig) SchemaURL() string {
+	return cfg.schemaURL
+}
+
+// MeterOption is an interface for applying Meter options.
+type MeterOption interface {
+	// applyMeter is used to set a MeterOption value of a MeterConfig.
+	applyMeter(MeterConfig) MeterConfig
+}
+
+// NewMeterConfig creates a new MeterConfig and applies
+// all the given options.
+func NewMeterConfig(opts ...MeterOption) MeterConfig {
+	var config MeterConfig
+	for _, o := range opts {
+		config = o.applyMeter(config)
+	}
+	return config
+}
+
+type meterOptionFunc func(MeterConfig) MeterConfig
+
+func (fn meterOptionFunc) applyMeter(cfg MeterConfig) MeterConfig {
+	return fn(cfg)
+}
+
+// WithInstrumentationVersion sets the instrumentation version.
+func WithInstrumentationVersion(version string) MeterOption {
+	return meterOptionFunc(func(config MeterConfig) MeterConfig {
+		config.instrumentationVersion = version
+		return config
+	})
+}
+
+// WithSchemaURL sets the schema URL.
+func WithSchemaURL(schemaURL string) MeterOption {
+	return meterOptionFunc(func(config MeterConfig) MeterConfig {
+		config.schemaURL = schemaURL
+		return config
+	})
+}