Unify api/label and api/kv in new label package (#1060)

* Move `api/label` to `label`

* Move `api/kv` package contents into `label` package

* Unify label package name

* Move `api/internal/rawhelpers.go` to `internal`

* Propagate replacing `api/kv` with `label` pkg

* golint

* Fix over-aggressive change

* Update Changelog

CHANGELOG.md

@@ -20,6 +20,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - The environment variable used for resource detection has been changed from `OTEL_RESOURCE_LABELS` to `OTEL_RESOURCE_ATTRIBUTES` (#1042)
 - Replace `WithSyncer` with `WithBatcher` in examples. (#1044)
 - Replace the `google.golang.org/grpc/codes` dependency in the API with an equivalent `go.opentelemetry.io/otel/codes` package. (#1046)
+- Merge the `go.opentelemetry.io/otel/api/label` and `go.opentelemetry.io/otel/api/kv` into the new `go.opentelemetry.io/otel/label` package. (#1060)
 - Unify Callback Function Naming.
    Rename `*Callback` with `*Func`. (#1061)
 

api/apitest/harness.go

@@ -20,10 +20,10 @@ import (
 	"testing"
 	"time"
 
-	"go.opentelemetry.io/otel/api/kv"
 	"go.opentelemetry.io/otel/api/trace"
 	"go.opentelemetry.io/otel/codes"
 	"go.opentelemetry.io/otel/internal/matchers"
+	"go.opentelemetry.io/otel/label"
 )
 
 type Harness struct {
@@ -195,7 +195,7 @@ func (h *Harness) testSpan(tracerFactory func() trace.Tracer) {
 			span.SetName("new name")
 		},
 		"#SetAttributes": func(span trace.Span) {
-			span.SetAttributes(kv.String("key1", "value"), kv.Int("key2", 123))
+			span.SetAttributes(label.String("key1", "value"), label.Int("key2", 123))
 		},
 	}
 	var mechanisms = map[string]func() trace.Span{

api/correlation/context.go

@@ -17,7 +17,7 @@ package correlation
 import (
 	"context"
 
-	"go.opentelemetry.io/otel/api/kv"
+	"go.opentelemetry.io/otel/label"
 )
 
 type correlationsType struct{}
@@ -150,7 +150,7 @@ func ContextWithMap(ctx context.Context, m Map) context.Context {
 
 // NewContext returns a context with the map from passed context
 // updated with the passed key-value pairs.
-func NewContext(ctx context.Context, keyvalues ...kv.KeyValue) context.Context {
+func NewContext(ctx context.Context, keyvalues ...label.KeyValue) context.Context {
 	return ContextWithMap(ctx, MapFromContext(ctx).Apply(MapUpdate{
 		MultiKV: keyvalues,
 	}))

api/correlation/correlation_context_propagator.go

@@ -19,8 +19,8 @@ import (
 	"net/url"
 	"strings"
 
-	"go.opentelemetry.io/otel/api/kv"
 	"go.opentelemetry.io/otel/api/propagation"
+	"go.opentelemetry.io/otel/label"
 )
 
 // Temporary header name until W3C finalizes format.
@@ -45,7 +45,7 @@ func (CorrelationContext) Inject(ctx context.Context, supplier propagation.HTTPS
 	correlationCtx := MapFromContext(ctx)
 	firstIter := true
 	var headerValueBuilder strings.Builder
-	correlationCtx.Foreach(func(kv kv.KeyValue) bool {
+	correlationCtx.Foreach(func(kv label.KeyValue) bool {
 		if !firstIter {
 			headerValueBuilder.WriteRune(',')
 		}
@@ -69,7 +69,7 @@ func (CorrelationContext) Extract(ctx context.Context, supplier propagation.HTTP
 	}
 
 	contextValues := strings.Split(correlationContext, ",")
-	keyValues := make([]kv.KeyValue, 0, len(contextValues))
+	keyValues := make([]label.KeyValue, 0, len(contextValues))
 	for _, contextValue := range contextValues {
 		valueAndProps := strings.Split(contextValue, ";")
 		if len(valueAndProps) < 1 {
@@ -99,7 +99,7 @@ func (CorrelationContext) Extract(ctx context.Context, supplier propagation.HTTP
 			trimmedValueWithProps.WriteString(prop)
 		}
 
-		keyValues = append(keyValues, kv.Key(trimmedName).String(trimmedValueWithProps.String()))
+		keyValues = append(keyValues, label.String(trimmedName, trimmedValueWithProps.String()))
 	}
 
 	if len(keyValues) > 0 {

api/correlation/correlation_context_propagator_test.go

@@ -23,63 +23,63 @@ import (
 	"github.com/google/go-cmp/cmp"
 
 	"go.opentelemetry.io/otel/api/correlation"
-	"go.opentelemetry.io/otel/api/kv"
 	"go.opentelemetry.io/otel/api/propagation"
+	"go.opentelemetry.io/otel/label"
 )
 
 func TestExtractValidDistributedContextFromHTTPReq(t *testing.T) {
 	props := propagation.New(propagation.WithExtractors(correlation.CorrelationContext{}))
 	tests := []struct {
 		name    string
 		header  string
-		wantKVs []kv.KeyValue
+		wantKVs []label.KeyValue
 	}{
 		{
 			name:   "valid w3cHeader",
 			header: "key1=val1,key2=val2",
-			wantKVs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2"),
+			wantKVs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2"),
 			},
 		},
 		{
 			name:   "valid w3cHeader with spaces",
 			header: "key1 =   val1,  key2 =val2   ",
-			wantKVs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2"),
+			wantKVs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2"),
 			},
 		},
 		{
 			name:   "valid w3cHeader with properties",
 			header: "key1=val1,key2=val2;prop=1",
-			wantKVs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2;prop=1"),
+			wantKVs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2;prop=1"),
 			},
 		},
 		{
 			name:   "valid header with url-escaped comma",
 			header: "key1=val1,key2=val2%2Cval3",
-			wantKVs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2,val3"),
+			wantKVs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2,val3"),
 			},
 		},
 		{
 			name:   "valid header with an invalid header",
 			header: "key1=val1,key2=val2,a,val3",
-			wantKVs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2"),
+			wantKVs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2"),
 			},
 		},
 		{
 			name:   "valid header with no value",
 			header: "key1=,key2=val2",
-			wantKVs: []kv.KeyValue{
-				kv.Key("key1").String(""),
-				kv.Key("key2").String("val2"),
+			wantKVs: []label.KeyValue{
+				label.String("key1", ""),
+				label.String("key2", "val2"),
 			},
 		},
 	}
@@ -101,9 +101,9 @@ func TestExtractValidDistributedContextFromHTTPReq(t *testing.T) {
 				)
 			}
 			totalDiff := ""
-			wantCorCtx.Foreach(func(keyValue kv.KeyValue) bool {
+			wantCorCtx.Foreach(func(keyValue label.KeyValue) bool {
 				val, _ := gotCorCtx.Value(keyValue.Key)
-				diff := cmp.Diff(keyValue, kv.KeyValue{Key: keyValue.Key, Value: val}, cmp.AllowUnexported(kv.Value{}))
+				diff := cmp.Diff(keyValue, label.KeyValue{Key: keyValue.Key, Value: val}, cmp.AllowUnexported(label.Value{}))
 				if diff != "" {
 					totalDiff += diff + "\n"
 				}
@@ -121,7 +121,7 @@ func TestExtractInvalidDistributedContextFromHTTPReq(t *testing.T) {
 	tests := []struct {
 		name   string
 		header string
-		hasKVs []kv.KeyValue
+		hasKVs []label.KeyValue
 	}{
 		{
 			name:   "no key values",
@@ -130,17 +130,17 @@ func TestExtractInvalidDistributedContextFromHTTPReq(t *testing.T) {
 		{
 			name:   "invalid header with existing context",
 			header: "header2",
-			hasKVs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2"),
+			hasKVs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2"),
 			},
 		},
 		{
 			name:   "empty header value",
 			header: "",
-			hasKVs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2"),
+			hasKVs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2"),
 			},
 		},
 	}
@@ -162,9 +162,9 @@ func TestExtractInvalidDistributedContextFromHTTPReq(t *testing.T) {
 				)
 			}
 			totalDiff := ""
-			wantCorCtx.Foreach(func(keyValue kv.KeyValue) bool {
+			wantCorCtx.Foreach(func(keyValue label.KeyValue) bool {
 				val, _ := gotCorCtx.Value(keyValue.Key)
-				diff := cmp.Diff(keyValue, kv.KeyValue{Key: keyValue.Key, Value: val}, cmp.AllowUnexported(kv.Value{}))
+				diff := cmp.Diff(keyValue, label.KeyValue{Key: keyValue.Key, Value: val}, cmp.AllowUnexported(label.Value{}))
 				if diff != "" {
 					totalDiff += diff + "\n"
 				}
@@ -179,38 +179,38 @@ func TestInjectCorrelationContextToHTTPReq(t *testing.T) {
 	props := propagation.New(propagation.WithInjectors(propagator))
 	tests := []struct {
 		name         string
-		kvs          []kv.KeyValue
+		kvs          []label.KeyValue
 		wantInHeader []string
 		wantedLen    int
 	}{
 		{
 			name: "two simple values",
-			kvs: []kv.KeyValue{
-				kv.Key("key1").String("val1"),
-				kv.Key("key2").String("val2"),
+			kvs: []label.KeyValue{
+				label.String("key1", "val1"),
+				label.String("key2", "val2"),
 			},
 			wantInHeader: []string{"key1=val1", "key2=val2"},
 		},
 		{
 			name: "two values with escaped chars",
-			kvs: []kv.KeyValue{
-				kv.Key("key1").String("val1,val2"),
-				kv.Key("key2").String("val3=4"),
+			kvs: []label.KeyValue{
+				label.String("key1", "val1,val2"),
+				label.String("key2", "val3=4"),
 			},
 			wantInHeader: []string{"key1=val1%2Cval2", "key2=val3%3D4"},
 		},
 		{
 			name: "values of non-string types",
-			kvs: []kv.KeyValue{
-				kv.Key("key1").Bool(true),
-				kv.Key("key2").Int(123),
-				kv.Key("key3").Int64(123),
-				kv.Key("key4").Int32(123),
-				kv.Key("key5").Uint(123),
-				kv.Key("key6").Uint32(123),
-				kv.Key("key7").Uint64(123),
-				kv.Key("key8").Float64(123.567),
-				kv.Key("key9").Float32(123.567),
+			kvs: []label.KeyValue{
+				label.Bool("key1", true),
+				label.Int("key2", 123),
+				label.Int64("key3", 123),
+				label.Int32("key4", 123),
+				label.Uint("key5", 123),
+				label.Uint32("key6", 123),
+				label.Uint64("key7", 123),
+				label.Float64("key8", 123.567),
+				label.Float32("key9", 123.567),
 			},
 			wantInHeader: []string{
 				"key1=true",

api/correlation/map.go

@@ -14,12 +14,10 @@
 
 package correlation
 
-import (
-	"go.opentelemetry.io/otel/api/kv"
-)
+import "go.opentelemetry.io/otel/label"
 
-type rawMap map[kv.Key]kv.Value
-type keySet map[kv.Key]struct{}
+type rawMap map[label.Key]label.Value
+type keySet map[label.Key]struct{}
 
 // Map is an immutable storage for correlations.
 type Map struct {
@@ -32,18 +30,18 @@ type MapUpdate struct {
 	// DropSingleK contains a single key to be dropped from
 	// correlations. Use this to avoid an overhead of a slice
 	// allocation if there is only one key to drop.
-	DropSingleK kv.Key
+	DropSingleK label.Key
 	// DropMultiK contains all the keys to be dropped from
 	// correlations.
-	DropMultiK []kv.Key
+	DropMultiK []label.Key
 
 	// SingleKV contains a single key-value pair to be added to
 	// correlations. Use this to avoid an overhead of a slice
 	// allocation if there is only one key-value pair to add.
-	SingleKV kv.KeyValue
+	SingleKV label.KeyValue
 	// MultiKV contains all the key-value pairs to be added to
 	// correlations.
-	MultiKV []kv.KeyValue
+	MultiKV []label.KeyValue
 }
 
 func newMap(raw rawMap) Map {
@@ -101,7 +99,7 @@ func getModificationSets(update MapUpdate) (delSet, addSet keySet) {
 		deletionsCount++
 	}
 	if deletionsCount > 0 {
-		delSet = make(map[kv.Key]struct{}, deletionsCount)
+		delSet = make(map[label.Key]struct{}, deletionsCount)
 		for _, k := range update.DropMultiK {
 			delSet[k] = struct{}{}
 		}
@@ -115,7 +113,7 @@ func getModificationSets(update MapUpdate) (delSet, addSet keySet) {
 		additionsCount++
 	}
 	if additionsCount > 0 {
-		addSet = make(map[kv.Key]struct{}, additionsCount)
+		addSet = make(map[label.Key]struct{}, additionsCount)
 		for _, k := range update.MultiKV {
 			addSet[k.Key] = struct{}{}
 		}
@@ -146,14 +144,14 @@ func getNewMapSize(m rawMap, delSet, addSet keySet) int {
 
 // Value gets a value from correlations map and returns a boolean
 // value indicating whether the key exist in the map.
-func (m Map) Value(k kv.Key) (kv.Value, bool) {
+func (m Map) Value(k label.Key) (label.Value, bool) {
 	value, ok := m.m[k]
 	return value, ok
 }
 
 // HasValue returns a boolean value indicating whether the key exist
 // in the map.
-func (m Map) HasValue(k kv.Key) bool {
+func (m Map) HasValue(k label.Key) bool {
 	_, has := m.Value(k)
 	return has
 }
@@ -166,9 +164,9 @@ func (m Map) Len() int {
 // Foreach calls a passed callback once on each key-value pair until
 // all the key-value pairs of the map were iterated or the callback
 // returns false, whichever happens first.
-func (m Map) Foreach(f func(kv kv.KeyValue) bool) {
+func (m Map) Foreach(f func(label.KeyValue) bool) {
 	for k, v := range m.m {
-		if !f(kv.KeyValue{
+		if !f(label.KeyValue{
 			Key:   k,
 			Value: v,
 		}) {