Add an example, link it in the README

examples/metrics/metrics_test.go

@@ -24,7 +24,7 @@ import (
 )
 
 func TestMinimumConfiguration(t *testing.T) {
-	server := test.NewServer(t)
+	server := test.NewServer()
 	defer server.Stop()
 
 	os.Setenv("LS_SERVICE_NAME", "test-service-name")

examples/tracing/trace_test.go

@@ -24,7 +24,7 @@ import (
 )
 
 func TestMinimumConfiguration(t *testing.T) {
-	server := test.NewServer(t)
+	server := test.NewServer()
 	defer server.Stop()
 
 	os.Setenv("LS_SERVICE_NAME", "test-service-name")

launcher/config_test.go

@@ -51,7 +51,7 @@ type testSuite struct {
 }
 
 func (suite *testSuite) SetupSuite() {
-	suite.Server = test.NewServer(suite.T())
+	suite.Server = test.NewServer()
 }
 
 func (suite *testSuite) SetupTest() {

lightstep/sdk/metric/README.md

@@ -45,6 +45,12 @@ Moreover, Lightstep expects to make several optimizations in this SDK
 to further optimize the synchronous instrument fast path and continue
 improving memory performance.
 
+### Using the Lightstep Metrics SDK directly
+
+See the example in
+[examples/example_test.go](./examples/example_test.go) for an example
+using this SDK with minimum configuration.
+
 ### Metric instrument "Hints" API
 
 There is a standing feature request in OpenTelemetry for a "Hints" API

lightstep/sdk/metric/example/doc.go

@@ -0,0 +1,20 @@
+// 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.
+
+// example demonstrates how to use the Lightstep metrics SDK with a
+// minimum of configuration.
+package example
+
+// MinimumConfig is tested in example_test.go.
+const MinimumConfig = ""

lightstep/sdk/metric/example/example_test.go

@@ -0,0 +1,72 @@
+// 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 example
+
+import (
+	"context"
+	"fmt"
+	"time"
+
+	// Note the SDK, exporter, and test appratus are from this repository
+	lightstep "github.com/lightstep/otel-launcher-go/lightstep/sdk/metric"
+	exporter "github.com/lightstep/otel-launcher-go/lightstep/sdk/metric/exporters/otlp"
+	otlptest "github.com/lightstep/otel-launcher-go/pipelines/test"
+
+	// Note the gRPC/OTLP exporter and protocol are from the community SDK.
+	otlpmetricgrpc "go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
+	otlpproto "go.opentelemetry.io/proto/otlp/metrics/v1"
+)
+
+// ExampleMinimumConfig tests the minimum configuration for a single point.
+func ExampleMinimumConfig() {
+	ctx := context.Background()
+	server := otlptest.NewServer()
+
+	// Configure an exporter.
+	exp, _ := exporter.New(ctx, otlpmetricgrpc.NewClient(
+
+		// In a real scenario, replace the following three lines with, for example:
+		//    WithEndpoint("ingest.lightstep.com:443").
+		//    WithHeaders(map[string]string{"lightstep-access-token": "${YOUR_ACCESS_TOKEN}"}),
+		otlpmetricgrpc.WithInsecure(),
+		otlpmetricgrpc.WithEndpoint(fmt.Sprint(otlptest.ServerName, ":", server.InsecureMetricsPort)),
+		otlpmetricgrpc.WithHeaders(map[string]string{"lightstep-access-token": "${TOKEN}"}),
+	))
+
+	// Configure the SDK.
+	sdk := lightstep.NewMeterProvider(
+		lightstep.WithReader(lightstep.NewPeriodicReader(exp, 30*time.Second)),
+	)
+
+	// Configure a Meter and instrument.
+	meter := sdk.Meter("meter")
+	counter, _ := meter.SyncInt64().Counter("how-many")
+
+	// Count once and shutdown.
+	counter.Add(ctx, 1)
+	sdk.Shutdown(ctx)
+
+	oneScope := server.MetricsRequests()[0].ResourceMetrics[0].ScopeMetrics[0]
+	oneHeader := server.MetricsMDs()[0]
+
+	fmt.Println(
+		oneScope.Scope.Name,
+		oneScope.Metrics[0].Name,
+		oneScope.Metrics[0].Data.(*otlpproto.Metric_Sum).Sum.DataPoints[0].Value.(*otlpproto.NumberDataPoint_AsInt).AsInt,
+		oneHeader["lightstep-access-token"][0],
+	)
+
+	// Output: meter how-many 1 ${TOKEN}
+}

lightstep/sdk/metric/example/go.mod

@@ -0,0 +1,37 @@
+module github.com/lightstep/otel-launcher-go/lightstep/sdk/metric/example
+
+go 1.18
+
+require (
+	github.com/lightstep/otel-launcher-go/lightstep/sdk/metric v1.8.0
+	github.com/lightstep/otel-launcher-go/pipelines v1.8.0
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v0.31.0
+	go.opentelemetry.io/proto/otlp v0.18.0
+)
+
+require (
+	github.com/cenkalti/backoff/v4 v4.1.3 // indirect
+	github.com/go-logr/logr v1.2.3 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.7.0 // indirect
+	go.opentelemetry.io/otel v1.8.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/internal/retry v1.8.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric v0.31.0 // indirect
+	go.opentelemetry.io/otel/metric v0.31.0 // indirect
+	go.opentelemetry.io/otel/sdk v1.8.0 // indirect
+	go.opentelemetry.io/otel/sdk/metric v0.31.0 // indirect
+	go.opentelemetry.io/otel/trace v1.8.0 // indirect
+	go.uber.org/atomic v1.7.0 // indirect
+	go.uber.org/multierr v1.8.0 // indirect
+	golang.org/x/net v0.0.0-20220111093109-d55c255bac03 // indirect
+	golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a // indirect
+	golang.org/x/text v0.3.7 // indirect
+	google.golang.org/genproto v0.0.0-20220112215332-a9c7c0acf9f2 // indirect
+	google.golang.org/grpc v1.46.2 // indirect
+	google.golang.org/protobuf v1.28.0 // indirect
+)
+
+replace github.com/lightstep/otel-launcher-go/lightstep/sdk/metric => ../
+
+replace github.com/lightstep/otel-launcher-go/pipelines => ../../../../pipelines