From 5f694b2e3eac01ba81615ff14dac3fe3b3a137f3 Mon Sep 17 00:00:00 2001
From: Joshua MacDonald <jmacd@users.noreply.github.com>
Date: Sun, 11 Oct 2020 11:46:29 -0700
Subject: [PATCH] Move asyncronous metrics state helper out of
 apimetric/metrictes (#1234)

---
 api/metric/metrictest/meter.go                |  5 +++--
 .../metrictest => internal/metric}/async.go   | 22 +++++++++----------
 sdk/metric/sdk.go                             |  2 +-
 3 files changed, 15 insertions(+), 14 deletions(-)
 rename {api/metric/metrictest => internal/metric}/async.go (88%)

diff --git a/api/metric/metrictest/meter.go b/api/metric/metrictest/meter.go
index 40524cac33c..fb0a817d1ef 100644
--- a/api/metric/metrictest/meter.go
+++ b/api/metric/metrictest/meter.go
@@ -21,6 +21,7 @@ import (
 	"go.opentelemetry.io/otel/api/metric"
 	apimetric "go.opentelemetry.io/otel/api/metric"
 	"go.opentelemetry.io/otel/api/metric/registry"
+	internalmetric "go.opentelemetry.io/otel/internal/metric"
 	"go.opentelemetry.io/otel/label"
 )
 
@@ -44,7 +45,7 @@ type (
 
 		MeasurementBatches []Batch
 
-		asyncInstruments *AsyncInstrumentState
+		asyncInstruments *internalmetric.AsyncInstrumentState
 	}
 
 	Measurement struct {
@@ -115,7 +116,7 @@ func (m *MeterImpl) doRecordSingle(ctx context.Context, labels []label.KeyValue,
 
 func NewMeterProvider() (*MeterImpl, apimetric.MeterProvider) {
 	impl := &MeterImpl{
-		asyncInstruments: NewAsyncInstrumentState(),
+		asyncInstruments: internalmetric.NewAsyncInstrumentState(),
 	}
 	return impl, registry.NewMeterProvider(impl)
 }
diff --git a/api/metric/metrictest/async.go b/internal/metric/async.go
similarity index 88%
rename from api/metric/metrictest/async.go
rename to internal/metric/async.go
index cd908f2e2b0..c2096f8c96f 100644
--- a/api/metric/metrictest/async.go
+++ b/internal/metric/async.go
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-package metrictest
+package metric
 
 import (
 	"context"
@@ -21,7 +21,7 @@ import (
 	"sync"
 
 	"go.opentelemetry.io/otel/api/global"
-	"go.opentelemetry.io/otel/api/metric"
+	api "go.opentelemetry.io/otel/api/metric"
 	"go.opentelemetry.io/otel/label"
 )
 
@@ -32,7 +32,7 @@ var ErrInvalidAsyncRunner = errors.New("unknown async runner type")
 // the SDK to provide support for running observer callbacks.
 type AsyncCollector interface {
 	// CollectAsync passes a batch of observations to the MeterImpl.
-	CollectAsync(labels []label.KeyValue, observation ...metric.Observation)
+	CollectAsync(labels []label.KeyValue, observation ...api.Observation)
 }
 
 // AsyncInstrumentState manages an ordered set of asynchronous
@@ -60,18 +60,18 @@ type AsyncInstrumentState struct {
 
 	// instruments maintains the set of instruments in the order
 	// they were registered.
-	instruments []metric.AsyncImpl
+	instruments []api.AsyncImpl
 }
 
 // asyncRunnerPair is a map entry for Observer callback runners.
 type asyncRunnerPair struct {
 	// runner is used as a map key here.  The API ensures
 	// that all callbacks are pointers for this reason.
-	runner metric.AsyncRunner
+	runner api.AsyncRunner
 
 	// inst refers to a non-nil instrument when `runner` is a
 	// AsyncSingleRunner.
-	inst metric.AsyncImpl
+	inst api.AsyncImpl
 }
 
 // NewAsyncInstrumentState returns a new *AsyncInstrumentState, for
@@ -86,7 +86,7 @@ func NewAsyncInstrumentState() *AsyncInstrumentState {
 // Instruments returns the asynchronous instruments managed by this
 // object, the set that should be checkpointed after observers are
 // run.
-func (a *AsyncInstrumentState) Instruments() []metric.AsyncImpl {
+func (a *AsyncInstrumentState) Instruments() []api.AsyncImpl {
 	a.lock.Lock()
 	defer a.lock.Unlock()
 	return a.instruments
@@ -96,7 +96,7 @@ func (a *AsyncInstrumentState) Instruments() []metric.AsyncImpl {
 // object.  This should be called during NewAsyncInstrument() and
 // assumes that errors (e.g., duplicate registration) have already
 // been checked.
-func (a *AsyncInstrumentState) Register(inst metric.AsyncImpl, runner metric.AsyncRunner) {
+func (a *AsyncInstrumentState) Register(inst api.AsyncImpl, runner api.AsyncRunner) {
 	a.lock.Lock()
 	defer a.lock.Unlock()
 
@@ -110,7 +110,7 @@ func (a *AsyncInstrumentState) Register(inst metric.AsyncImpl, runner metric.Asy
 	rp := asyncRunnerPair{
 		runner: runner,
 	}
-	if _, ok := runner.(metric.AsyncSingleRunner); ok {
+	if _, ok := runner.(api.AsyncSingleRunner); ok {
 		rp.inst = inst
 	}
 
@@ -131,12 +131,12 @@ func (a *AsyncInstrumentState) Run(ctx context.Context, collector AsyncCollector
 		// other implementations are possible because the
 		// interface has un-exported methods.
 
-		if singleRunner, ok := rp.runner.(metric.AsyncSingleRunner); ok {
+		if singleRunner, ok := rp.runner.(api.AsyncSingleRunner); ok {
 			singleRunner.Run(ctx, rp.inst, collector.CollectAsync)
 			continue
 		}
 
-		if multiRunner, ok := rp.runner.(metric.AsyncBatchRunner); ok {
+		if multiRunner, ok := rp.runner.(api.AsyncBatchRunner); ok {
 			multiRunner.Run(ctx, collector.CollectAsync)
 			continue
 		}
diff --git a/sdk/metric/sdk.go b/sdk/metric/sdk.go
index 4e16f279828..50ee358e384 100644
--- a/sdk/metric/sdk.go
+++ b/sdk/metric/sdk.go
@@ -24,7 +24,7 @@ import (
 	"go.opentelemetry.io/otel/api/global"
 	"go.opentelemetry.io/otel/api/metric"
 	api "go.opentelemetry.io/otel/api/metric"
-	internal "go.opentelemetry.io/otel/api/metric/metrictest"
+	internal "go.opentelemetry.io/otel/internal/metric"
 	"go.opentelemetry.io/otel/label"
 	export "go.opentelemetry.io/otel/sdk/export/metric"
 	"go.opentelemetry.io/otel/sdk/metric/aggregator"