fix prometheus example

example/prometheus/main.go

@@ -27,14 +27,13 @@ import (
 	"go.opentelemetry.io/otel/metric"
 	"go.opentelemetry.io/otel/metric/instrument"
 	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
-	"go.opentelemetry.io/otel/sdk/metric/views"
+	"go.opentelemetry.io/otel/sdk/metric/view"
 	"go.opentelemetry.io/otel/sdk/resource"
 )
 
 var (
 	lemonsKey = attribute.Key("ex.com/lemons")
 
-	// TODO Bring back Global package
 	meterProvider metric.MeterProvider
 )
 
@@ -45,20 +44,20 @@ func initMeter() metric.MeterProvider {
 	}
 
 	sdk := sdkmetric.New(
-		sdkmetric.WithReader(exporter),
 		sdkmetric.WithResource(resource.NewSchemaless(attribute.String("resource", "etc"))),
-		sdkmetric.WithViews(
-			views.New(
-				views.MatchInstrumentName("ex.com.one"),
-				views.WithName("example_one"),
+		sdkmetric.WithReader(
+			exporter,
+			view.WithClause(
+				view.MatchInstrumentName("ex.com.one"),
+				view.WithName("example_one"),
 			),
-			views.New(
-				views.MatchInstrumentName("ex.com.two"),
-				views.WithName("example_two"),
+			view.WithClause(
+				view.MatchInstrumentName("ex.com.two"),
+				view.WithName("example_two"),
 			),
-			views.New(
-				views.MatchInstrumentName("ex.com.three"),
-				views.WithName("example_three"),
+			view.WithClause(
+				view.MatchInstrumentName("ex.com.three"),
+				view.WithName("example_three"),
 			),
 		),
 	)

exporters/prometheus/prometheus.go

@@ -28,9 +28,9 @@ import (
 
 	"go.opentelemetry.io/otel"
 	"go.opentelemetry.io/otel/attribute"
+	"go.opentelemetry.io/otel/sdk/metric"
 	"go.opentelemetry.io/otel/sdk/metric/aggregator/aggregation"
 	"go.opentelemetry.io/otel/sdk/metric/number"
-	"go.opentelemetry.io/otel/sdk/metric/reader"
 	"go.opentelemetry.io/otel/sdk/metric/sdkinstrument"
 	"go.opentelemetry.io/otel/sdk/resource"
 )
@@ -44,10 +44,10 @@ type Exporter struct {
 	gatherer   prometheus.Gatherer
 
 	lock     sync.Mutex
-	producer reader.Producer
+	producer metric.Producer
 }
 
-var _ reader.Reader = &Exporter{}
+var _ metric.Reader = &Exporter{}
 var _ http.Handler = &Exporter{}
 
 // ErrUnsupportedAggregator is returned for unrepresentable aggregator
@@ -109,23 +109,23 @@ func (e *Exporter) String() string {
 	return "prometheus"
 }
 
-func (e *Exporter) Register(p reader.Producer) {
+func (e *Exporter) Register(p metric.Producer) {
 	e.lock.Lock()
 	defer e.lock.Unlock()
 	e.producer = p
 }
 
-func (e *Exporter) getProducer() reader.Producer {
+func (e *Exporter) getProducer() metric.Producer {
 	e.lock.Lock()
 	defer e.lock.Unlock()
 	return e.producer
 }
 
-func (e *Exporter) Flush(ctx context.Context) error {
+func (e *Exporter) ForceFlush(_ context.Context) error {
 	return nil
 }
 
-func (e *Exporter) Shutdown(ctx context.Context) error {
+func (e *Exporter) Shutdown(_ context.Context) error {
 	return nil
 }
 

sdk/metric/reader.go

@@ -20,48 +20,46 @@ import (
 	"go.opentelemetry.io/otel/sdk/metric/data"
 )
 
-type (
-	// Reader is the interface used between the SDK and an
-	// exporter.  Control flow is bi-directional through the
-	// Reader, since the SDK initiates ForceFlush and Shutdown
-	// while the initiates collection.  The Register() method here
-	// informs the Reader that it can begin reading, signaling the
-	// start of bi-directional control flow.
-	//
-	// Typically, push-based exporters that are periodic will
-	// implement PeroidicExporter themselves and construct a
-	// PeriodicReader to satisfy this interface.
-	//
-	// Pull-based exporters will typically implement Register
-	// themselves, since they read on demand.
-	Reader interface {
-		// String describes this reader.
-		String() string
+// Reader is the interface used between the SDK and an
+// exporter.  Control flow is bi-directional through the
+// Reader, since the SDK initiates ForceFlush and Shutdown
+// while the initiates collection.  The Register() method here
+// informs the Reader that it can begin reading, signaling the
+// start of bi-directional control flow.
+//
+// Typically, push-based exporters that are periodic will
+// implement PeroidicExporter themselves and construct a
+// PeriodicReader to satisfy this interface.
+//
+// Pull-based exporters will typically implement Register
+// themselves, since they read on demand.
+type Reader interface {
+	// String describes this reader.
+	String() string
 
-		// Register is called when the SDK is fully
-		// configured.  The Producer passed allows the
-		// Reader to begin collecting metrics using its
-		// Produce() method.
-		Register(Producer)
+	// Register is called when the SDK is fully
+	// configured.  The Producer passed allows the
+	// Reader to begin collecting metrics using its
+	// Produce() method.
+	Register(Producer)
 
-		// ForceFlush is called when MeterProvider.ForceFlush() is called.
-		ForceFlush(context.Context) error
+	// ForceFlush is called when MeterProvider.ForceFlush() is called.
+	ForceFlush(context.Context) error
 
-		// Shutdown is called when MeterProvider.Shutdown() is called.
-		Shutdown(context.Context) error
-	}
+	// Shutdown is called when MeterProvider.Shutdown() is called.
+	Shutdown(context.Context) error
+}
 
-	// Producer is the interface used to perform collection by the reader.
-	Producer interface {
-		// Produce returns metrics from a single collection.
-		//
-		// Produce may be called concurrently,
-		//
-		// The `in` parameter supports re-use of memory from
-		// one collection to the next.  Callers that pass `in`
-		// will write metrics into the same slices and structs.
-		//
-		// When `in` is nil, a new Metrics object is returned.
-		Produce(in *data.Metrics) data.Metrics
-	}
-)
+// Producer is the interface used to perform collection by the reader.
+type Producer interface {
+	// Produce returns metrics from a single collection.
+	//
+	// Produce may be called concurrently,
+	//
+	// The `in` parameter supports re-use of memory from
+	// one collection to the next.  Callers that pass `in`
+	// will write metrics into the same slices and structs.
+	//
+	// When `in` is nil, a new Metrics object is returned.
+	Produce(in *data.Metrics) data.Metrics
+}