Remove Context arguments from Aggregator.Checkpoint and Integrator.Process (#803)

* Typo

* Swap order of ddsketch.New for consistency w/ histogram.New

* Remove Integrator.Process ctx argument

* Remove Aggregator.Checkpoint ctx argument

* Revert bugfix

api/global/internal/benchmark_test.go

@@ -71,7 +71,7 @@ func (*benchFixture) AggregatorFor(descriptor *metric.Descriptor) export.Aggrega
 	return nil
 }
 
-func (*benchFixture) Process(context.Context, export.Record) error {
+func (*benchFixture) Process(export.Record) error {
 	return nil
 }
 

exporters/metric/stdout/stdout_test.go

@@ -101,7 +101,7 @@ func TestStdoutTimestamp(t *testing.T) {
 	desc := metric.NewDescriptor("test.name", metric.ValueObserverKind, metric.Int64NumberKind)
 	lvagg := lastvalue.New()
 	aggtest.CheckedUpdate(t, lvagg, metric.NewInt64Number(321), &desc)
-	lvagg.Checkpoint(ctx, &desc)
+	lvagg.Checkpoint(&desc)
 
 	checkpointSet.Add(&desc, lvagg)
 
@@ -146,7 +146,7 @@ func TestStdoutCounterFormat(t *testing.T) {
 	desc := metric.NewDescriptor("test.name", metric.CounterKind, metric.Int64NumberKind)
 	cagg := sum.New()
 	aggtest.CheckedUpdate(fix.t, cagg, metric.NewInt64Number(123), &desc)
-	cagg.Checkpoint(fix.ctx, &desc)
+	cagg.Checkpoint(&desc)
 
 	checkpointSet.Add(&desc, cagg, kv.String("A", "B"), kv.String("C", "D"))
 
@@ -163,7 +163,7 @@ func TestStdoutLastValueFormat(t *testing.T) {
 	desc := metric.NewDescriptor("test.name", metric.ValueObserverKind, metric.Float64NumberKind)
 	lvagg := lastvalue.New()
 	aggtest.CheckedUpdate(fix.t, lvagg, metric.NewFloat64Number(123.456), &desc)
-	lvagg.Checkpoint(fix.ctx, &desc)
+	lvagg.Checkpoint(&desc)
 
 	checkpointSet.Add(&desc, lvagg, kv.String("A", "B"), kv.String("C", "D"))
 
@@ -181,7 +181,7 @@ func TestStdoutMinMaxSumCount(t *testing.T) {
 	magg := minmaxsumcount.New(&desc)
 	aggtest.CheckedUpdate(fix.t, magg, metric.NewFloat64Number(123.456), &desc)
 	aggtest.CheckedUpdate(fix.t, magg, metric.NewFloat64Number(876.543), &desc)
-	magg.Checkpoint(fix.ctx, &desc)
+	magg.Checkpoint(&desc)
 
 	checkpointSet.Add(&desc, magg, kv.String("A", "B"), kv.String("C", "D"))
 
@@ -204,7 +204,7 @@ func TestStdoutValueRecorderFormat(t *testing.T) {
 		aggtest.CheckedUpdate(fix.t, magg, metric.NewFloat64Number(float64(i)+0.5), &desc)
 	}
 
-	magg.Checkpoint(fix.ctx, &desc)
+	magg.Checkpoint(&desc)
 
 	checkpointSet.Add(&desc, magg, kv.String("A", "B"), kv.String("C", "D"))
 
@@ -252,7 +252,7 @@ func TestStdoutNoData(t *testing.T) {
 			checkpointSet := test.NewCheckpointSet(testResource)
 
 			magg := tc
-			magg.Checkpoint(fix.ctx, &desc)
+			magg.Checkpoint(&desc)
 
 			checkpointSet.Add(&desc, magg)
 
@@ -270,7 +270,7 @@ func TestStdoutLastValueNotSet(t *testing.T) {
 
 	desc := metric.NewDescriptor("test.name", metric.ValueObserverKind, metric.Float64NumberKind)
 	lvagg := lastvalue.New()
-	lvagg.Checkpoint(fix.ctx, &desc)
+	lvagg.Checkpoint(&desc)
 
 	checkpointSet.Add(&desc, lvagg, kv.String("A", "B"), kv.String("C", "D"))
 
@@ -321,7 +321,7 @@ func TestStdoutResource(t *testing.T) {
 		desc := metric.NewDescriptor("test.name", metric.ValueObserverKind, metric.Float64NumberKind)
 		lvagg := lastvalue.New()
 		aggtest.CheckedUpdate(fix.t, lvagg, metric.NewFloat64Number(123.456), &desc)
-		lvagg.Checkpoint(fix.ctx, &desc)
+		lvagg.Checkpoint(&desc)
 
 		checkpointSet.Add(&desc, lvagg, tc.attrs...)
 

exporters/metric/test/test.go

@@ -105,7 +105,7 @@ func (p *CheckpointSet) updateAggregator(desc *metric.Descriptor, newAgg export.
 	ctx := context.Background()
 	// Updates and checkpoint the new aggregator
 	_ = newAgg.Update(ctx, createNumber(desc, v), desc)
-	newAgg.Checkpoint(ctx, desc)
+	newAgg.Checkpoint(desc)
 
 	// Try to add this aggregator to the CheckpointSet
 	agg, added := p.Add(desc, newAgg, labels...)

exporters/otlp/internal/transform/metric_test.go

@@ -89,7 +89,7 @@ func TestMinMaxSumCountValue(t *testing.T) {
 	assert.EqualError(t, err, aggregator.ErrNoData.Error())
 
 	// Checkpoint to set non-zero values
-	mmsc.Checkpoint(context.Background(), &metric.Descriptor{})
+	mmsc.Checkpoint(&metric.Descriptor{})
 	min, max, sum, count, err := minMaxSumCountValues(mmsc)
 	if assert.NoError(t, err) {
 		assert.Equal(t, min, metric.NewInt64Number(1))
@@ -146,7 +146,7 @@ func TestMinMaxSumCountMetricDescriptor(t *testing.T) {
 	if !assert.NoError(t, mmsc.Update(ctx, 1, &metric.Descriptor{})) {
 		return
 	}
-	mmsc.Checkpoint(ctx, &metric.Descriptor{})
+	mmsc.Checkpoint(&metric.Descriptor{})
 	for _, test := range tests {
 		desc := metric.NewDescriptor(test.name, test.metricKind, test.numberKind,
 			metric.WithDescription(test.description),
@@ -165,7 +165,7 @@ func TestMinMaxSumCountDatapoints(t *testing.T) {
 	mmsc := minmaxsumcount.New(&desc)
 	assert.NoError(t, mmsc.Update(context.Background(), 1, &desc))
 	assert.NoError(t, mmsc.Update(context.Background(), 10, &desc))
-	mmsc.Checkpoint(context.Background(), &desc)
+	mmsc.Checkpoint(&desc)
 	expected := []*metricpb.SummaryDataPoint{
 		{
 			Count: 2,
@@ -261,7 +261,7 @@ func TestSumInt64DataPoints(t *testing.T) {
 	labels := label.NewSet()
 	s := sumAgg.New()
 	assert.NoError(t, s.Update(context.Background(), metric.Number(1), &desc))
-	s.Checkpoint(context.Background(), &desc)
+	s.Checkpoint(&desc)
 	if m, err := sum(&desc, &labels, s); assert.NoError(t, err) {
 		assert.Equal(t, []*metricpb.Int64DataPoint{{Value: 1}}, m.Int64DataPoints)
 		assert.Equal(t, []*metricpb.DoubleDataPoint(nil), m.DoubleDataPoints)
@@ -275,7 +275,7 @@ func TestSumFloat64DataPoints(t *testing.T) {
 	labels := label.NewSet()
 	s := sumAgg.New()
 	assert.NoError(t, s.Update(context.Background(), metric.NewFloat64Number(1), &desc))
-	s.Checkpoint(context.Background(), &desc)
+	s.Checkpoint(&desc)
 	if m, err := sum(&desc, &labels, s); assert.NoError(t, err) {
 		assert.Equal(t, []*metricpb.Int64DataPoint(nil), m.Int64DataPoints)
 		assert.Equal(t, []*metricpb.DoubleDataPoint{{Value: 1}}, m.DoubleDataPoints)

exporters/otlp/otlp_metric_test.go

@@ -657,7 +657,7 @@ func runMetricExportTest(t *testing.T, exp *Exporter, rs []record, expected []me
 		default:
 			t.Fatalf("invalid number kind: %v", r.nKind)
 		}
-		agg.Checkpoint(ctx, &desc)
+		agg.Checkpoint(&desc)
 
 		equiv := r.resource.Equivalent()
 		resources[equiv] = r.resource

sdk/export/metric/metric.go

@@ -62,11 +62,12 @@ type Integrator interface {
 
 	// Process is called by the SDK once per internal record,
 	// passing the export Record (a Descriptor, the corresponding
-	// Labels, and the checkpointed Aggregator).
+	// Labels, and the checkpointed Aggregator).  This call has no
-	//
+	// Context argument because it is expected to perform only
-	// The Context argument originates from the controller that
+	// computation.  An SDK is not expected to call exporters from
-	// orchestrates collection.
+	// with Process, use a controller for that (see
-	Process(ctx context.Context, record Record) error
+	// ./controllers/{pull,push}.
+	Process(record Record) error
 }
 
 // AggregationSelector supports selecting the kind of Aggregator to
@@ -119,9 +120,9 @@ type Aggregator interface {
 	// accessed using by converting to one a suitable interface
 	// types in the `aggregator` sub-package.
 	//
-	// The Context argument originates from the controller that
+	// This call has no Context argument because it is expected to
-	// orchestrates collection.
+	// perform only computation.
-	Checkpoint(context.Context, *metric.Descriptor)
+	Checkpoint(*metric.Descriptor)
 
 	// Merge combines the checkpointed state from the argument
 	// aggregator into this aggregator's checkpointed state.

sdk/metric/aggregator/array/array.go

@@ -85,7 +85,7 @@ func (c *Aggregator) Points() ([]metric.Number, error) {
 
 // Checkpoint saves the current state and resets the current state to
 // the empty set, taking a lock to prevent concurrent Update() calls.
-func (c *Aggregator) Checkpoint(ctx context.Context, desc *metric.Descriptor) {
+func (c *Aggregator) Checkpoint(desc *metric.Descriptor) {
 	c.lock.Lock()
 	c.checkpoint, c.current = c.current, nil
 	c.lock.Unlock()

sdk/metric/aggregator/array/array_test.go

@@ -15,7 +15,6 @@
 package array
 
 import (
-	"context"
 	"fmt"
 	"math"
 	"os"
@@ -66,8 +65,7 @@ func (ut *updateTest) run(t *testing.T, profile test.Profile) {
 		test.CheckedUpdate(t, agg, y, descriptor)
 	}
 
-	ctx := context.Background()
+	agg.Checkpoint(descriptor)
-	agg.Checkpoint(ctx, descriptor)
 
 	all.Sort()
 
@@ -116,8 +114,6 @@ type mergeTest struct {
 }
 
 func (mt *mergeTest) run(t *testing.T, profile test.Profile) {
-	ctx := context.Background()
-
 	descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
 	agg1 := New()
@@ -145,8 +141,8 @@ func (mt *mergeTest) run(t *testing.T, profile test.Profile) {
 		}
 	}
 
-	agg1.Checkpoint(ctx, descriptor)
+	agg1.Checkpoint(descriptor)
-	agg2.Checkpoint(ctx, descriptor)
+	agg2.Checkpoint(descriptor)
 
 	test.CheckedMerge(t, agg1, agg2, descriptor)
 
@@ -213,8 +209,6 @@ func TestArrayErrors(t *testing.T) {
 		require.Error(t, err)
 		require.Equal(t, err, aggregator.ErrNoData)
 
-		ctx := context.Background()
-
 		descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
 		test.CheckedUpdate(t, agg, metric.Number(0), descriptor)
@@ -222,7 +216,7 @@ func TestArrayErrors(t *testing.T) {
 		if profile.NumberKind == metric.Float64NumberKind {
 			test.CheckedUpdate(t, agg, metric.NewFloat64Number(math.NaN()), descriptor)
 		}
-		agg.Checkpoint(ctx, descriptor)
+		agg.Checkpoint(descriptor)
 
 		count, err := agg.Count()
 		require.Equal(t, int64(1), count, "NaN value was not counted")
@@ -275,7 +269,6 @@ func TestArrayFloat64(t *testing.T) {
 
 	all := test.NewNumbers(metric.Float64NumberKind)
 
-	ctx := context.Background()
 	agg := New()
 
 	for _, f := range fpsf(1) {
@@ -288,7 +281,7 @@ func TestArrayFloat64(t *testing.T) {
 		test.CheckedUpdate(t, agg, metric.NewFloat64Number(f), descriptor)
 	}
 
-	agg.Checkpoint(ctx, descriptor)
+	agg.Checkpoint(descriptor)
 
 	all.Sort()
 

sdk/metric/aggregator/ddsketch/ddsketch.go

@@ -103,7 +103,7 @@ func (c *Aggregator) toNumber(f float64) metric.Number {
 
 // Checkpoint saves the current state and resets the current state to
 // the empty set, taking a lock to prevent concurrent Update() calls.
-func (c *Aggregator) Checkpoint(ctx context.Context, _ *metric.Descriptor) {
+func (c *Aggregator) Checkpoint(*metric.Descriptor) {
 	replace := sdk.NewDDSketch(c.cfg)
 
 	c.lock.Lock()

sdk/metric/aggregator/ddsketch/ddsketch_test.go

@@ -15,7 +15,6 @@
 package ddsketch
 
 import (
-	"context"
 	"fmt"
 	"testing"
 
@@ -31,8 +30,6 @@ type updateTest struct {
 }
 
 func (ut *updateTest) run(t *testing.T, profile test.Profile) {
-	ctx := context.Background()
-
 	descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 	agg := New(descriptor, NewDefaultConfig())
 
@@ -47,7 +44,7 @@ func (ut *updateTest) run(t *testing.T, profile test.Profile) {
 		test.CheckedUpdate(t, agg, y, descriptor)
 	}
 
-	agg.Checkpoint(ctx, descriptor)
+	agg.Checkpoint(descriptor)
 
 	all.Sort()
 
@@ -91,7 +88,6 @@ type mergeTest struct {
 }
 
 func (mt *mergeTest) run(t *testing.T, profile test.Profile) {
-	ctx := context.Background()
 	descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
 	agg1 := New(descriptor, NewDefaultConfig())
@@ -122,8 +118,8 @@ func (mt *mergeTest) run(t *testing.T, profile test.Profile) {
 		}
 	}
 
-	agg1.Checkpoint(ctx, descriptor)
+	agg1.Checkpoint(descriptor)
-	agg2.Checkpoint(ctx, descriptor)
+	agg2.Checkpoint(descriptor)
 
 	test.CheckedMerge(t, agg1, agg2, descriptor)
 

sdk/metric/aggregator/histogram/histogram.go

@@ -107,7 +107,7 @@ func (c *Aggregator) Histogram() (aggregator.Buckets, error) {
 // the empty set.  Since no locks are taken, there is a chance that
 // the independent Sum, Count and Bucket Count are not consistent with each
 // other.
-func (c *Aggregator) Checkpoint(ctx context.Context, desc *metric.Descriptor) {
+func (c *Aggregator) Checkpoint(desc *metric.Descriptor) {
 	c.lock.Lock()
 	c.checkpoint, c.current = c.current, emptyState(c.boundaries)
 	c.lock.Unlock()

sdk/metric/aggregator/histogram/histogram_test.go

@@ -15,7 +15,6 @@
 package histogram_test
 
 import (
-	"context"
 	"math"
 	"math/rand"
 	"sort"
@@ -81,7 +80,6 @@ func TestHistogramPositiveAndNegative(t *testing.T) {
 
 // Validates count, sum and buckets for a given profile and policy
 func testHistogram(t *testing.T, profile test.Profile, policy policy) {
-	ctx := context.Background()
 	descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
 	agg := histogram.New(descriptor, boundaries)
@@ -94,7 +92,7 @@ func testHistogram(t *testing.T, profile test.Profile, policy policy) {
 		test.CheckedUpdate(t, agg, x, descriptor)
 	}
 
-	agg.Checkpoint(ctx, descriptor)
+	agg.Checkpoint(descriptor)
 
 	all.Sort()
 
@@ -137,8 +135,6 @@ func TestHistogramInitial(t *testing.T) {
 }
 
 func TestHistogramMerge(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
@@ -158,8 +154,8 @@ func TestHistogramMerge(t *testing.T) {
 			test.CheckedUpdate(t, agg2, x, descriptor)
 		}
 
-		agg1.Checkpoint(ctx, descriptor)
+		agg1.Checkpoint(descriptor)
-		agg2.Checkpoint(ctx, descriptor)
+		agg2.Checkpoint(descriptor)
 
 		test.CheckedMerge(t, agg1, agg2, descriptor)
 
@@ -192,13 +188,11 @@ func TestHistogramMerge(t *testing.T) {
 }
 
 func TestHistogramNotSet(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
 		agg := histogram.New(descriptor, boundaries)
-		agg.Checkpoint(ctx, descriptor)
+		agg.Checkpoint(descriptor)
 
 		asum, err := agg.Sum()
 		require.Equal(t, metric.Number(0), asum, "Empty checkpoint sum = 0")

sdk/metric/aggregator/lastvalue/lastvalue.go

@@ -80,7 +80,7 @@ func (g *Aggregator) LastValue() (metric.Number, time.Time, error) {
 }
 
 // Checkpoint atomically saves the current value.
-func (g *Aggregator) Checkpoint(ctx context.Context, _ *metric.Descriptor) {
+func (g *Aggregator) Checkpoint(*metric.Descriptor) {
 	g.checkpoint = atomic.LoadPointer(&g.current)
 }
 

sdk/metric/aggregator/lastvalue/lastvalue_test.go

@@ -15,7 +15,6 @@
 package lastvalue
 
 import (
-	"context"
 	"math/rand"
 	"os"
 	"testing"
@@ -50,8 +49,6 @@ func TestMain(m *testing.M) {
 }
 
 func TestLastValueUpdate(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		agg := New()
 
@@ -64,7 +61,7 @@ func TestLastValueUpdate(t *testing.T) {
 			test.CheckedUpdate(t, agg, x, record)
 		}
 
-		agg.Checkpoint(ctx, record)
+		agg.Checkpoint(record)
 
 		lv, _, err := agg.LastValue()
 		require.Equal(t, last, lv, "Same last value - non-monotonic")
@@ -73,8 +70,6 @@ func TestLastValueUpdate(t *testing.T) {
 }
 
 func TestLastValueMerge(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		agg1 := New()
 		agg2 := New()
@@ -88,8 +83,8 @@ func TestLastValueMerge(t *testing.T) {
 		test.CheckedUpdate(t, agg1, first1, descriptor)
 		test.CheckedUpdate(t, agg2, first2, descriptor)
 
-		agg1.Checkpoint(ctx, descriptor)
+		agg1.Checkpoint(descriptor)
-		agg2.Checkpoint(ctx, descriptor)
+		agg2.Checkpoint(descriptor)
 
 		_, t1, err := agg1.LastValue()
 		require.Nil(t, err)
@@ -110,7 +105,7 @@ func TestLastValueNotSet(t *testing.T) {
 	descriptor := test.NewAggregatorTest(metric.ValueObserverKind, metric.Int64NumberKind)
 
 	g := New()
-	g.Checkpoint(context.Background(), descriptor)
+	g.Checkpoint(descriptor)
 
 	value, timestamp, err := g.LastValue()
 	require.Equal(t, aggregator.ErrNoData, err)

sdk/metric/aggregator/minmaxsumcount/mmsc.go

@@ -102,7 +102,7 @@ func (c *Aggregator) Max() (metric.Number, error) {
 
 // Checkpoint saves the current state and resets the current state to
 // the empty set.
-func (c *Aggregator) Checkpoint(ctx context.Context, desc *metric.Descriptor) {
+func (c *Aggregator) Checkpoint(desc *metric.Descriptor) {
 	c.lock.Lock()
 	c.checkpoint, c.current = c.current, c.emptyState()
 	c.lock.Unlock()

sdk/metric/aggregator/minmaxsumcount/mmsc_test.go

@@ -15,7 +15,6 @@
 package minmaxsumcount
 
 import (
-	"context"
 	"math"
 	"math/rand"
 	"testing"
@@ -78,7 +77,6 @@ func TestMinMaxSumCountPositiveAndNegative(t *testing.T) {
 
 // Validates min, max, sum and count for a given profile and policy
 func minMaxSumCount(t *testing.T, profile test.Profile, policy policy) {
-	ctx := context.Background()
 	descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
 	agg := New(descriptor)
@@ -91,7 +89,7 @@ func minMaxSumCount(t *testing.T, profile test.Profile, policy policy) {
 		test.CheckedUpdate(t, agg, x, descriptor)
 	}
 
-	agg.Checkpoint(ctx, descriptor)
+	agg.Checkpoint(descriptor)
 
 	all.Sort()
 
@@ -124,8 +122,6 @@ func minMaxSumCount(t *testing.T, profile test.Profile, policy policy) {
 }
 
 func TestMinMaxSumCountMerge(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
@@ -145,8 +141,8 @@ func TestMinMaxSumCountMerge(t *testing.T) {
 			test.CheckedUpdate(t, agg2, x, descriptor)
 		}
 
-		agg1.Checkpoint(ctx, descriptor)
+		agg1.Checkpoint(descriptor)
-		agg2.Checkpoint(ctx, descriptor)
+		agg2.Checkpoint(descriptor)
 
 		test.CheckedMerge(t, agg1, agg2, descriptor)
 
@@ -182,13 +178,11 @@ func TestMinMaxSumCountMerge(t *testing.T) {
 }
 
 func TestMaxSumCountNotSet(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		descriptor := test.NewAggregatorTest(metric.ValueRecorderKind, profile.NumberKind)
 
 		agg := New(descriptor)
-		agg.Checkpoint(ctx, descriptor)
+		agg.Checkpoint(descriptor)
 
 		asum, err := agg.Sum()
 		require.Equal(t, metric.Number(0), asum, "Empty checkpoint sum = 0")

sdk/metric/aggregator/sum/sum.go

@@ -51,7 +51,7 @@ func (c *Aggregator) Sum() (metric.Number, error) {
 
 // Checkpoint atomically saves the current value and resets the
 // current sum to zero.
-func (c *Aggregator) Checkpoint(ctx context.Context, _ *metric.Descriptor) {
+func (c *Aggregator) Checkpoint(*metric.Descriptor) {
 	c.checkpoint = c.current.SwapNumberAtomic(metric.Number(0))
 }
 

sdk/metric/aggregator/sum/sum_test.go

@@ -15,7 +15,6 @@
 package sum
 
 import (
-	"context"
 	"os"
 	"testing"
 	"unsafe"
@@ -49,8 +48,6 @@ func TestMain(m *testing.M) {
 }
 
 func TestCounterSum(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		agg := New()
 
@@ -63,7 +60,7 @@ func TestCounterSum(t *testing.T) {
 			test.CheckedUpdate(t, agg, x, descriptor)
 		}
 
-		agg.Checkpoint(ctx, descriptor)
+		agg.Checkpoint(descriptor)
 
 		asum, err := agg.Sum()
 		require.Equal(t, sum, asum, "Same sum - monotonic")
@@ -72,8 +69,6 @@ func TestCounterSum(t *testing.T) {
 }
 
 func TestValueRecorderSum(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		agg := New()
 
@@ -90,7 +85,7 @@ func TestValueRecorderSum(t *testing.T) {
 			sum.AddNumber(profile.NumberKind, r2)
 		}
 
-		agg.Checkpoint(ctx, descriptor)
+		agg.Checkpoint(descriptor)
 
 		asum, err := agg.Sum()
 		require.Equal(t, sum, asum, "Same sum - monotonic")
@@ -99,8 +94,6 @@ func TestValueRecorderSum(t *testing.T) {
 }
 
 func TestCounterMerge(t *testing.T) {
-	ctx := context.Background()
-
 	test.RunProfiles(t, func(t *testing.T, profile test.Profile) {
 		agg1 := New()
 		agg2 := New()
@@ -115,8 +108,8 @@ func TestCounterMerge(t *testing.T) {
 			test.CheckedUpdate(t, agg2, x, descriptor)
 		}
 
-		agg1.Checkpoint(ctx, descriptor)
+		agg1.Checkpoint(descriptor)
-		agg2.Checkpoint(ctx, descriptor)
+		agg2.Checkpoint(descriptor)
 
 		test.CheckedMerge(t, agg1, agg2, descriptor)
 

sdk/metric/benchmark_test.go

@@ -32,13 +32,10 @@ import (
 	"go.opentelemetry.io/otel/sdk/metric/aggregator/sum"
 )
 
-type processFunc func(context.Context, export.Record) error
-
 type benchFixture struct {
 	meter       metric.MeterMust
 	accumulator *sdk.Accumulator
 	B           *testing.B
-	pcb         processFunc
 }
 
 func newFixture(b *testing.B) *benchFixture {
@@ -52,10 +49,6 @@ func newFixture(b *testing.B) *benchFixture {
 	return bf
 }
 
-func (f *benchFixture) setProcessCallback(cb processFunc) {
-	f.pcb = cb
-}
-
 func (*benchFixture) AggregatorFor(descriptor *metric.Descriptor) export.Aggregator {
 	name := descriptor.Name()
 	switch {
@@ -75,11 +68,8 @@ func (*benchFixture) AggregatorFor(descriptor *metric.Descriptor) export.Aggrega
 	return nil
 }
 
-func (f *benchFixture) Process(ctx context.Context, rec export.Record) error {
+func (f *benchFixture) Process(rec export.Record) error {
-	if f.pcb == nil {
+	return nil
-		return nil
-	}
-	return f.pcb(ctx, rec)
 }
 
 func (*benchFixture) CheckpointSet() export.CheckpointSet {
@@ -201,28 +191,14 @@ func BenchmarkAcquireReleaseExistingHandle(b *testing.B) {
 var benchmarkIteratorVar kv.KeyValue
 
 func benchmarkIterator(b *testing.B, n int) {
-	fix := newFixture(b)
+	labels := label.NewSet(makeLabels(n)...)
-	fix.setProcessCallback(func(ctx context.Context, rec export.Record) error {
-		var kv kv.KeyValue
-		li := rec.Labels().Iter()
-		fix.B.StartTimer()
-		for i := 0; i < fix.B.N; i++ {
-			iter := li
-			// test getting only the first element
-			if iter.Next() {
-				kv = iter.Label()
-			}
-		}
-		fix.B.StopTimer()
-		benchmarkIteratorVar = kv
-		return nil
-	})
-	cnt := fix.meter.NewInt64Counter("int64.counter")
-	ctx := context.Background()
-	cnt.Add(ctx, 1, makeLabels(n)...)
-
 	b.ResetTimer()
-	fix.accumulator.Collect(ctx)
+	for i := 0; i < b.N; i++ {
+		iter := labels.Iter()
+		for iter.Next() {
+			benchmarkIteratorVar = iter.Label()
+		}
+	}
 }
 
 func BenchmarkIterator_0(b *testing.B) {
@@ -560,11 +536,6 @@ func BenchmarkBatchRecord_8Labels_8Instruments(b *testing.B) {
 func BenchmarkRepeatedDirectCalls(b *testing.B) {
 	ctx := context.Background()
 	fix := newFixture(b)
-	encoder := label.DefaultEncoder()
-	fix.pcb = func(_ context.Context, rec export.Record) error {
-		_ = rec.Labels().Encoded(encoder)
-		return nil
-	}
 
 	c := fix.meter.NewInt64Counter("int64.counter")
 	k := kv.String("bench", "true")
@@ -576,39 +547,3 @@ func BenchmarkRepeatedDirectCalls(b *testing.B) {
 		fix.accumulator.Collect(ctx)
 	}
 }
-
-// LabelIterator
-
-func BenchmarkLabelIterator(b *testing.B) {
-	const labelCount = 1024
-	ctx := context.Background()
-	fix := newFixture(b)
-
-	var rec export.Record
-	fix.pcb = func(_ context.Context, processRec export.Record) error {
-		rec = processRec
-		return nil
-	}
-
-	keyValues := makeLabels(labelCount)
-	counter := fix.meter.NewInt64Counter("test.counter")
-	counter.Add(ctx, 1, keyValues...)
-
-	fix.accumulator.Collect(ctx)
-
-	b.ResetTimer()
-
-	labels := rec.Labels()
-	iter := labels.Iter()
-	var val kv.KeyValue
-	for i := 0; i < b.N; i++ {
-		if !iter.Next() {
-			iter = labels.Iter()
-			iter.Next()
-		}
-		val = iter.Label()
-	}
-	if false {
-		fmt.Println(val)
-	}
-}

sdk/metric/correct_test.go

@@ -119,7 +119,7 @@ func (ci *correctnessIntegrator) CheckpointSet() export.CheckpointSet {
 func (*correctnessIntegrator) FinishedCollection() {
 }
 
-func (ci *correctnessIntegrator) Process(_ context.Context, record export.Record) error {
+func (ci *correctnessIntegrator) Process(record export.Record) error {
 	ci.records = append(ci.records, record)
 	return nil
 }

sdk/metric/histogram_stress_test.go

@@ -44,7 +44,7 @@ func TestStressInt64Histogram(t *testing.T) {
 
 	startTime := time.Now()
 	for time.Since(startTime) < time.Second {
-		h.Checkpoint(context.Background(), &desc)
+		h.Checkpoint(&desc)
 
 		b, _ := h.Histogram()
 		c, _ := h.Count()

sdk/metric/integrator/simple/simple.go

@@ -15,7 +15,6 @@
 package simple // import "go.opentelemetry.io/otel/sdk/metric/integrator/simple"
 
 import (
-	"context"
 	"errors"
 	"sync"
 
@@ -65,7 +64,7 @@ func New(selector export.AggregationSelector, stateful bool) *Integrator {
 	}
 }
 
-func (b *Integrator) Process(_ context.Context, record export.Record) error {
+func (b *Integrator) Process(record export.Record) error {
 	desc := record.Descriptor()
 	key := batchKey{
 		descriptor: desc,

sdk/metric/integrator/simple/simple_test.go

@@ -30,34 +30,33 @@ import (
 // These tests use the ../test label encoding.
 
 func TestSimpleStateless(t *testing.T) {
-	ctx := context.Background()
 	b := simple.New(test.NewAggregationSelector(), false)
 
 	// Set initial lastValue values
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueADesc, test.Labels1, 10))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueADesc, test.Labels1, 10))
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueADesc, test.Labels2, 20))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueADesc, test.Labels2, 20))
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueADesc, test.Labels3, 30))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueADesc, test.Labels3, 30))
 
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueBDesc, test.Labels1, 10))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueBDesc, test.Labels1, 10))
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueBDesc, test.Labels2, 20))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueBDesc, test.Labels2, 20))
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueBDesc, test.Labels3, 30))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueBDesc, test.Labels3, 30))
 
 	// Another lastValue Set for Labels1
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueADesc, test.Labels1, 50))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueADesc, test.Labels1, 50))
-	_ = b.Process(ctx, test.NewLastValueRecord(&test.LastValueBDesc, test.Labels1, 50))
+	_ = b.Process(test.NewLastValueRecord(&test.LastValueBDesc, test.Labels1, 50))
 
 	// Set initial counter values
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterADesc, test.Labels1, 10))
+	_ = b.Process(test.NewCounterRecord(&test.CounterADesc, test.Labels1, 10))
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterADesc, test.Labels2, 20))
+	_ = b.Process(test.NewCounterRecord(&test.CounterADesc, test.Labels2, 20))
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterADesc, test.Labels3, 40))
+	_ = b.Process(test.NewCounterRecord(&test.CounterADesc, test.Labels3, 40))
 
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterBDesc, test.Labels1, 10))
+	_ = b.Process(test.NewCounterRecord(&test.CounterBDesc, test.Labels1, 10))
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterBDesc, test.Labels2, 20))
+	_ = b.Process(test.NewCounterRecord(&test.CounterBDesc, test.Labels2, 20))
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterBDesc, test.Labels3, 40))
+	_ = b.Process(test.NewCounterRecord(&test.CounterBDesc, test.Labels3, 40))
 
 	// Another counter Add for Labels1
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterADesc, test.Labels1, 50))
+	_ = b.Process(test.NewCounterRecord(&test.CounterADesc, test.Labels1, 50))
-	_ = b.Process(ctx, test.NewCounterRecord(&test.CounterBDesc, test.Labels1, 50))
+	_ = b.Process(test.NewCounterRecord(&test.CounterBDesc, test.Labels1, 50))
 
 	checkpointSet := b.CheckpointSet()
 
@@ -97,11 +96,11 @@ func TestSimpleStateful(t *testing.T) {
 
 	counterA := test.NewCounterRecord(&test.CounterADesc, test.Labels1, 10)
 	caggA := counterA.Aggregator()
-	_ = b.Process(ctx, counterA)
+	_ = b.Process(counterA)
 
 	counterB := test.NewCounterRecord(&test.CounterBDesc, test.Labels1, 10)
 	caggB := counterB.Aggregator()
-	_ = b.Process(ctx, counterB)
+	_ = b.Process(counterB)
 
 	checkpointSet := b.CheckpointSet()
 	b.FinishedCollection()
@@ -126,8 +125,8 @@ func TestSimpleStateful(t *testing.T) {
 	// Update and re-checkpoint the original record.
 	_ = caggA.Update(ctx, metric.NewInt64Number(20), &test.CounterADesc)
 	_ = caggB.Update(ctx, metric.NewInt64Number(20), &test.CounterBDesc)
-	caggA.Checkpoint(ctx, &test.CounterADesc)
+	caggA.Checkpoint(&test.CounterADesc)
-	caggB.Checkpoint(ctx, &test.CounterBDesc)
+	caggB.Checkpoint(&test.CounterBDesc)
 
 	// As yet cagg has not been passed to Integrator.Process.  Should
 	// not see an update.
@@ -140,8 +139,8 @@ func TestSimpleStateful(t *testing.T) {
 	b.FinishedCollection()
 
 	// Now process the second update
-	_ = b.Process(ctx, export.NewRecord(&test.CounterADesc, test.Labels1, test.Resource, caggA))
+	_ = b.Process(export.NewRecord(&test.CounterADesc, test.Labels1, test.Resource, caggA))
-	_ = b.Process(ctx, export.NewRecord(&test.CounterBDesc, test.Labels1, test.Resource, caggB))
+	_ = b.Process(export.NewRecord(&test.CounterBDesc, test.Labels1, test.Resource, caggB))
 
 	checkpointSet = b.CheckpointSet()
 

sdk/metric/integrator/test/test.go

@@ -131,7 +131,7 @@ func LastValueAgg(desc *metric.Descriptor, v int64) export.Aggregator {
 	ctx := context.Background()
 	gagg := lastvalue.New()
 	_ = gagg.Update(ctx, metric.NewInt64Number(v), desc)
-	gagg.Checkpoint(ctx, desc)
+	gagg.Checkpoint(desc)
 	return gagg
 }
 
@@ -150,7 +150,7 @@ func CounterAgg(desc *metric.Descriptor, v int64) export.Aggregator {
 	ctx := context.Background()
 	cagg := sum.New()
 	_ = cagg.Update(ctx, metric.NewInt64Number(v), desc)
-	cagg.Checkpoint(ctx, desc)
+	cagg.Checkpoint(desc)
 	return cagg
 }
 

sdk/metric/minmaxsumcount_stress_test.go

@@ -46,7 +46,7 @@ func TestStressInt64MinMaxSumCount(t *testing.T) {
 
 	startTime := time.Now()
 	for time.Since(startTime) < time.Second {
-		mmsc.Checkpoint(context.Background(), &desc)
+		mmsc.Checkpoint(&desc)
 
 		s, _ := mmsc.Sum()
 		c, _ := mmsc.Count()

sdk/metric/sdk.go

@@ -50,7 +50,6 @@ type (
 		// `*asyncInstrument` instances
 		asyncLock        sync.Mutex
 		asyncInstruments *internal.AsyncInstrumentState
-		asyncContext     context.Context
 
 		// currentEpoch is the current epoch number. It is
 		// incremented in `Collect()`.
@@ -354,13 +353,13 @@ func (m *Accumulator) Collect(ctx context.Context) int {
 	defer m.collectLock.Unlock()
 
 	checkpointed := m.observeAsyncInstruments(ctx)
-	checkpointed += m.collectSyncInstruments(ctx)
+	checkpointed += m.collectSyncInstruments()
 	m.currentEpoch++
 
 	return checkpointed
 }
 
-func (m *Accumulator) collectSyncInstruments(ctx context.Context) int {
+func (m *Accumulator) collectSyncInstruments() int {
 	checkpointed := 0
 
 	m.current.Range(func(key interface{}, value interface{}) bool {
@@ -374,7 +373,7 @@ func (m *Accumulator) collectSyncInstruments(ctx context.Context) int {
 		if mods != coll {
 			// Updates happened in this interval,
 			// checkpoint and continue.
-			checkpointed += m.checkpointRecord(ctx, inuse)
+			checkpointed += m.checkpointRecord(inuse)
 			inuse.collectedCount = mods
 			return true
 		}
@@ -395,7 +394,7 @@ func (m *Accumulator) collectSyncInstruments(ctx context.Context) int {
 		// last we'll see of this record, checkpoint
 		mods = atomic.LoadInt64(&inuse.updateCount)
 		if mods != coll {
-			checkpointed += m.checkpointRecord(ctx, inuse)
+			checkpointed += m.checkpointRecord(inuse)
 		}
 		return true
 	})
@@ -419,10 +418,9 @@ func (m *Accumulator) observeAsyncInstruments(ctx context.Context) int {
 	defer m.asyncLock.Unlock()
 
 	asyncCollected := 0
-	m.asyncContext = ctx
 
+	// TODO: change this to `ctx` (in a separate PR, with tests)
 	m.asyncInstruments.Run(context.Background(), m)
-	m.asyncContext = nil
 
 	for _, inst := range m.asyncInstruments.Instruments() {
 		if a := m.fromAsync(inst); a != nil {
@@ -433,8 +431,8 @@ func (m *Accumulator) observeAsyncInstruments(ctx context.Context) int {
 	return asyncCollected
 }
 
-func (m *Accumulator) checkpointRecord(ctx context.Context, r *record) int {
+func (m *Accumulator) checkpointRecord(r *record) int {
-	return m.checkpoint(ctx, &r.inst.descriptor, r.recorder, r.labels)
+	return m.checkpoint(&r.inst.descriptor, r.recorder, r.labels)
 }
 
 func (m *Accumulator) checkpointAsync(a *asyncInstrument) int {
@@ -446,7 +444,7 @@ func (m *Accumulator) checkpointAsync(a *asyncInstrument) int {
 		lrec := lrec
 		epochDiff := m.currentEpoch - lrec.observedEpoch
 		if epochDiff == 0 {
-			checkpointed += m.checkpoint(m.asyncContext, &a.descriptor, lrec.recorder, lrec.labels)
+			checkpointed += m.checkpoint(&a.descriptor, lrec.recorder, lrec.labels)
 		} else if epochDiff > 1 {
 			// This is second collection cycle with no
 			// observations for this labelset. Remove the
@@ -460,14 +458,14 @@ func (m *Accumulator) checkpointAsync(a *asyncInstrument) int {
 	return checkpointed
 }
 
-func (m *Accumulator) checkpoint(ctx context.Context, descriptor *metric.Descriptor, recorder export.Aggregator, labels *label.Set) int {
+func (m *Accumulator) checkpoint(descriptor *metric.Descriptor, recorder export.Aggregator, labels *label.Set) int {
 	if recorder == nil {
 		return 0
 	}
-	recorder.Checkpoint(ctx, descriptor)
+	recorder.Checkpoint(descriptor)
 
 	exportRecord := export.NewRecord(descriptor, labels, m.resource, recorder)
-	err := m.integrator.Process(ctx, exportRecord)
+	err := m.integrator.Process(exportRecord)
 	if err != nil {
 		global.Handle(err)
 	}

sdk/metric/stress_test.go

@@ -263,7 +263,7 @@ func (*testFixture) CheckpointSet() export.CheckpointSet {
 func (*testFixture) FinishedCollection() {
 }
 
-func (f *testFixture) Process(_ context.Context, record export.Record) error {
+func (f *testFixture) Process(record export.Record) error {
 	labels := record.Labels().ToSlice()
 	key := testKey{
 		labels:     canonicalizeLabels(labels),