[OTEL-2540] update SpanContext JSON tags to match OTel API Specification

Author: jackgopack4

CHANGELOG.md

@@ -34,6 +34,7 @@ This project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.htm
 - `go.opentelemetry.io/otel/sdk/log/logtest` is now a separate Go module. (#6466)
 - `Recorder` in `go.opentelemetry.io/otel/log/logtest` no longer separately stores records emitted by loggers with the same instrumentation scope. (#6507)
 - Improve performance of `BatchProcessor` in `go.opentelemetry.io/otel/sdk/log` by not exporting when exporter cannot accept more. (#6569, #6641)
+- Update JSON tags for `TraceId`, `SpanId`, and `IsRemote` in `go.opentelemetry.io/otel/trace` to match [OpenTelemetry API specification for SpanContext items](https://github.com/open-telemetry/opentelemetry-specification/blob/815598814f3cf461ad5493ccbddd53633fb5cf24/specification/trace/api.md#spancontext) (#6738)
 
 ### Deprecated
 

exporters/stdout/stdouttrace/trace_test.go

@@ -106,18 +106,18 @@ func expectedJSON(now time.Time) string {
 	return `{
 	"Name": "/foo",
 	"SpanContext": {
-		"TraceID": "0102030405060708090a0b0c0d0e0f10",
-		"SpanID": "0102030405060708",
+		"TraceId": "0102030405060708090a0b0c0d0e0f10",
+		"SpanId": "0102030405060708",
 		"TraceFlags": "00",
 		"TraceState": "key=val",
-		"Remote": false
+		"IsRemote": false
 	},
 	"Parent": {
-		"TraceID": "00000000000000000000000000000000",
-		"SpanID": "0000000000000000",
+		"TraceId": "00000000000000000000000000000000",
+		"SpanId": "0000000000000000",
 		"TraceFlags": "00",
 		"TraceState": "",
-		"Remote": false
+		"IsRemote": false
 	},
 	"SpanKind": 1,
 	"StartTime": ` + string(serializedNow) + `,

trace/trace.go

@@ -230,12 +230,14 @@ func (tf *TraceFlags) UnmarshalJSON(data []byte) error {
 
 // SpanContextConfig contains mutable fields usable for constructing
 // an immutable SpanContext.
+// JSON tags match OTel API Specification:
+// https://github.com/open-telemetry/opentelemetry-specification/blob/815598814f3cf461ad5493ccbddd53633fb5cf24/specification/trace/api.md#spancontext
 type SpanContextConfig struct {
-	TraceID    TraceID
-	SpanID     SpanID
-	TraceFlags TraceFlags
-	TraceState TraceState
-	Remote     bool
+	TraceID    TraceID    `json:"TraceId"`
+	SpanID     SpanID     `json:"SpanId"`
+	TraceFlags TraceFlags `json:"TraceFlags"`
+	TraceState TraceState `json:"TraceState"`
+	Remote     bool       `json:"IsRemote"`
 }
 
 // NewSpanContext constructs a SpanContext using values from the provided

trace/trace_test.go

@@ -151,7 +151,7 @@ func TestSpanContextMarshalJSON(t *testing.T) {
 			name: "SpanContext.MarshalJSON() returns json with partial data",
 			tid:  [16]byte{1},
 			sid:  [8]byte{42},
-			want: []byte(`{"TraceID":"01000000000000000000000000000000","SpanID":"2a00000000000000","TraceFlags":"00","TraceState":"","Remote":false}`),
+			want: []byte(`{"TraceId":"01000000000000000000000000000000","SpanId":"2a00000000000000","TraceFlags":"00","TraceState":"","IsRemote":false}`),
 		},
 		{
 			name:     "SpanContext.MarshalJSON() returns json with full data",
@@ -162,7 +162,7 @@ func TestSpanContextMarshalJSON(t *testing.T) {
 			tstate: TraceState{list: []member{
 				{Key: "foo", Value: "1"},
 			}},
-			want: []byte(`{"TraceID":"01000000000000000000000000000000","SpanID":"2a00000000000000","TraceFlags":"01","TraceState":"foo=1","Remote":true}`),
+			want: []byte(`{"TraceId":"01000000000000000000000000000000","SpanId":"2a00000000000000","TraceFlags":"01","TraceState":"foo=1","IsRemote":true}`),
 		},
 	} {
 		t.Run(testcase.name, func(t *testing.T) {
@@ -761,7 +761,7 @@ func TestSpanContextUnmarshalJSON(t *testing.T) {
 	}{
 		{
 			name:  "valid full SpanContext",
-			input: `{"TraceID":"01000000000000000000000000000000","SpanID":"2a00000000000000","TraceFlags":"01","TraceState":"foo=1","Remote":true}`,
+			input: `{"TraceId":"01000000000000000000000000000000","SpanId":"2a00000000000000","TraceFlags":"01","TraceState":"foo=1","IsRemote":true}`,
 			want: NewSpanContext(SpanContextConfig{
 				TraceID:    TraceID{0x01},
 				SpanID:     SpanID{0x2a},
@@ -772,20 +772,20 @@ func TestSpanContextUnmarshalJSON(t *testing.T) {
 		},
 		{
 			name:  "valid partial SpanContext",
-			input: `{"TraceID":"01000000000000000000000000000000","SpanID":"2a00000000000000"}`,
+			input: `{"TraceId":"01000000000000000000000000000000","SpanId":"2a00000000000000"}`,
 			want: NewSpanContext(SpanContextConfig{
 				TraceID: TraceID{0x01},
 				SpanID:  SpanID{0x2a},
 			}),
 		},
 		{
 			name:    "invalid TraceID",
-			input:   `{"TraceID":"00000000000000000000000000000000","SpanID":"2a00000000000000"}`,
+			input:   `{"TraceId":"00000000000000000000000000000000","SpanId":"2a00000000000000"}`,
 			wantErr: true,
 		},
 		{
 			name:    "invalid JSON",
-			input:   `{"TraceID:123}`,
+			input:   `{"TraceId:123}`,
 			wantErr: true,
 		},
 	}