Remove InstrumentKind and Scope from Stream

open-telemetry · Nov 11, 2022 · 3bdcf8a · 3bdcf8a
1 parent a350588
commit 3bdcf8a
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Showing 3 changed files with 64 additions and 120 deletions.
diff --git a/sdk/metric/instrument.go b/sdk/metric/instrument.go
@@ -85,34 +85,6 @@ type Instrument struct {
 	nonComparable // nolint: unused
 }
 
-// mask returns a copy of base with all non-zero-value fields of m replacing
-// the fields of the returned copy.
-func (base Instrument) mask(m Instrument) Instrument {
-	cp := base
-	if m.Name != "" {
-		cp.Name = m.Name
-	}
-	if m.Description != "" {
-		cp.Description = m.Description
-	}
-	if m.Kind != zeroInstrumentKind {
-		cp.Kind = m.Kind
-	}
-	if m.Unit != zeroUnit {
-		cp.Unit = m.Unit
-	}
-	if m.Scope.Name != "" {
-		cp.Scope.Name = m.Scope.Name
-	}
-	if m.Scope.Version != "" {
-		cp.Scope.Version = m.Scope.Version
-	}
-	if m.Scope.SchemaURL != "" {
-		cp.Scope.SchemaURL = m.Scope.SchemaURL
-	}
-	return cp
-}
-
 // empty returns if all fields of i are their zero-value.
 func (i Instrument) empty() bool {
 	return i.Name == "" &&
@@ -167,8 +139,12 @@ func (i Instrument) matchesScope(other Instrument) bool {
 
 // Stream describes the stream of data an instrument produces.
 type Stream struct {
-	Instrument
-
+	// Name is the human-readable identifier of the stream.
+	Name string
+	// Description describes the purpose of the data.
+	Description string
+	// Unit is the unit of measurement recorded.
+	Unit unit.Unit
 	// Aggregation the stream uses for an instrument.
 	Aggregation aggregation.Aggregation
 	// AttributeFilter applied to all attributes recorded for an instrument.

diff --git a/sdk/metric/view.go b/sdk/metric/view.go
@@ -48,11 +48,11 @@ type View func(Instrument) (Stream, bool)
 // all instrument names.
 //
 // The Stream mask only applies updates for non-zero-value fields. By default,
-// the Instrument the View matches against will be use for the returned Stream
-// and no Aggregation or AttributeFilter are set. If mask has a non-zero-value
-// value for any of the Aggregation or AttributeFilter fields, or any of the
-// Instrument fields, that value is used instead of the default. If you need to
-// zero out an Stream field returned from a View, create a View directly.
+// the Instrument the View matches against will be use for the Name,
+// Description, and Unit of the returned Stream and no Aggregation or
+// AttributeFilter are set. All non-zero-value value fields of mask are used
+// instead of the default. If you need to zero out an Stream field returned
+// from a View, create a View directly.
 func NewView(criteria Instrument, mask Stream) View {
 	if criteria.empty() {
 		return emptyView
@@ -102,13 +102,23 @@ func NewView(criteria Instrument, mask Stream) View {
 
 	return func(i Instrument) (Stream, bool) {
 		if matchFunc(i) {
-			stream := Stream{
-				Instrument:      i.mask(mask.Instrument),
+			return Stream{
+				Name:            nonZero(mask.Name, i.Name),
+				Description:     nonZero(mask.Description, i.Description),
+				Unit:            nonZero(mask.Unit, i.Unit),
 				Aggregation:     agg,
 				AttributeFilter: mask.AttributeFilter,
-			}
-			return stream, true
+			}, true
 		}
 		return Stream{}, false
 	}
 }
+
+// nonZero returns v if it is non-zero-valued, otherwise alt.
+func nonZero[T comparable](v, alt T) T {
+	var zero T
+	if v != zero {
+		return v
+	}
+	return alt
+}
diff --git a/sdk/metric/view_test.go b/sdk/metric/view_test.go
@@ -350,114 +350,72 @@ func TestNewViewReplace(t *testing.T) {
 	}{
 		{
 			name: "Nothing",
-			want: func(ip Instrument) Stream {
-				return Stream{Instrument: ip}
+			want: func(i Instrument) Stream {
+				return Stream{
+					Name:        i.Name,
+					Description: i.Description,
+					Unit:        i.Unit,
+				}
 			},
 		},
 		{
 			name: "Name",
-			mask: Stream{Instrument: Instrument{Name: alt}},
-			want: func(ip Instrument) Stream {
-				ip.Name = alt
-				return Stream{Instrument: ip}
+			mask: Stream{Name: alt},
+			want: func(i Instrument) Stream {
+				return Stream{
+					Name:        alt,
+					Description: i.Description,
+					Unit:        i.Unit,
+				}
 			},
 		},
 		{
 			name: "Description",
-			mask: Stream{Instrument: Instrument{Description: alt}},
-			want: func(ip Instrument) Stream {
-				ip.Description = alt
-				return Stream{Instrument: ip}
-			},
-		},
-		{
-			name: "Kind",
-			mask: Stream{Instrument: Instrument{
-				Kind: InstrumentKindAsyncUpDownCounter,
-			}},
-			want: func(ip Instrument) Stream {
-				ip.Kind = InstrumentKindAsyncUpDownCounter
-				return Stream{Instrument: ip}
+			mask: Stream{Description: alt},
+			want: func(i Instrument) Stream {
+				return Stream{
+					Name:        i.Name,
+					Description: alt,
+					Unit:        i.Unit,
+				}
 			},
 		},
 		{
 			name: "Unit",
-			mask: Stream{Instrument: Instrument{Unit: unit.Dimensionless}},
-			want: func(ip Instrument) Stream {
-				ip.Unit = unit.Dimensionless
-				return Stream{Instrument: ip}
-			},
-		},
-		{
-			name: "ScopeName",
-			mask: Stream{Instrument: Instrument{Scope: scope(alt, "", "")}},
-			want: func(ip Instrument) Stream {
-				ip.Scope.Name = alt
-				return Stream{Instrument: ip}
-			},
-		},
-		{
-			name: "ScopeVersion",
-			mask: Stream{Instrument: Instrument{Scope: scope("", alt, "")}},
-			want: func(ip Instrument) Stream {
-				ip.Scope.Version = alt
-				return Stream{Instrument: ip}
-			},
-		},
-		{
-			name: "ScopeSchemaURL",
-			mask: Stream{Instrument: Instrument{Scope: scope("", "", alt)}},
-			want: func(ip Instrument) Stream {
-				ip.Scope.SchemaURL = alt
-				return Stream{Instrument: ip}
-			},
-		},
-		{
-			name: "Scope",
-			mask: Stream{Instrument: Instrument{
-				Scope: scope("Alt Scope Name", "1.1.1", "https://go.dev"),
-			}},
-			want: func(ip Instrument) Stream {
-				ip.Scope.Name = "Alt Scope Name"
-				ip.Scope.Version = "1.1.1"
-				ip.Scope.SchemaURL = "https://go.dev"
-				return Stream{Instrument: ip}
+			mask: Stream{Unit: unit.Dimensionless},
+			want: func(i Instrument) Stream {
+				return Stream{
+					Name:        i.Name,
+					Description: i.Description,
+					Unit:        unit.Dimensionless,
+				}
 			},
 		},
 		{
 			name: "Aggregation",
-			mask: Stream{
-				Aggregation: aggregation.LastValue{},
-			},
-			want: func(ip Instrument) Stream {
+			mask: Stream{Aggregation: aggregation.LastValue{}},
+			want: func(i Instrument) Stream {
 				return Stream{
-					Instrument:  ip,
+					Name:        i.Name,
+					Description: i.Description,
+					Unit:        i.Unit,
 					Aggregation: aggregation.LastValue{},
 				}
 			},
 		},
 		{
 			name: "Complete",
 			mask: Stream{
-				Instrument: Instrument{
-					Name:        alt,
-					Description: alt,
-					Kind:        InstrumentKindAsyncUpDownCounter,
-					Unit:        unit.Dimensionless,
-					Scope:       scope(alt, alt, alt),
-				},
+				Name:        alt,
+				Description: alt,
+				Unit:        unit.Dimensionless,
 				Aggregation: aggregation.LastValue{},
 			},
-			want: func(ip Instrument) Stream {
-				ip.Name = alt
-				ip.Description = alt
-				ip.Kind = InstrumentKindAsyncUpDownCounter
-				ip.Unit = unit.Dimensionless
-				ip.Scope.Name = alt
-				ip.Scope.Version = alt
-				ip.Scope.SchemaURL = alt
+			want: func(i Instrument) Stream {
 				return Stream{
-					Instrument:  ip,
+					Name:        alt,
+					Description: alt,
+					Unit:        unit.Dimensionless,
 					Aggregation: aggregation.LastValue{},
 				}
 			},