Unmarshal span and link flags from JSON (#11275)

For both the `Span` and `SpanLink`, the current unmarshalJsoniter
methods do not unmarshal the `flags` field. This updates the
functionality to correctly decode these values into the destination.

Fix #11267

Signed-off-by: Tyler Yahn <codingalias@gmail.com>

---------

Signed-off-by: Tyler Yahn <codingalias@gmail.com>
Co-authored-by: Bogdan Drutu <bogdandrutu@gmail.com>
Co-authored-by: Alex Boten <223565+codeboten@users.noreply.github.com>

.chloggen/json-decoded-flag.yaml

@@ -0,0 +1,25 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'bug_fix'
+
+# The name of the component, or a single word describing the area of concern, (e.g. otlpreceiver)
+component: 'pdata'
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Unmarshal Span and SpanLink flags from JSON"
+
+# One or more tracking issues or pull requests related to the change
+issues: [11267]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:
+
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

pdata/ptrace/json.go

@@ -112,6 +112,8 @@ func (dest Span) unmarshalJsoniter(iter *jsoniter.Iterator) {
 			if err := dest.orig.ParentSpanId.UnmarshalJSON([]byte(iter.ReadString())); err != nil {
 				iter.ReportError("readSpan.parentSpanId", fmt.Sprintf("parse parent_span_id:%v", err))
 			}
+		case "flags":
+			dest.orig.Flags = iter.ReadUint32()
 		case "name":
 			dest.orig.Name = iter.ReadString()
 		case "kind":
@@ -184,6 +186,8 @@ func (dest SpanLink) unmarshalJsoniter(iter *jsoniter.Iterator) {
 			})
 		case "droppedAttributesCount", "dropped_attributes_count":
 			dest.orig.DroppedAttributesCount = json.ReadUint32(iter)
+		case "flags":
+			dest.orig.Flags = json.ReadUint32(iter)
 		default:
 			iter.Skip()
 		}

pdata/ptrace/json_test.go

@@ -37,6 +37,7 @@ var tracesOTLP = func() Traces {
 	il.SetSchemaUrl("schemaURL")
 	// Add spans.
 	sp := il.Spans().AppendEmpty()
+	sp.SetFlags(1)
 	sp.SetName("testSpan")
 	sp.SetKind(SpanKindClient)
 	sp.SetDroppedAttributesCount(1)
@@ -83,13 +84,14 @@ var tracesOTLP = func() Traces {
 	link.Attributes().PutInt("int", 1)
 	link.Attributes().PutDouble("double", 1.1)
 	link.Attributes().PutEmptyBytes("bytes").FromRaw([]byte("foo"))
+	link.SetFlags(1)
 	// Add another span.
 	sp2 := il.Spans().AppendEmpty()
 	sp2.SetName("testSpan2")
 	return td
 }()
 
-var tracesJSON = `{"resourceSpans":[{"resource":{"attributes":[{"key":"host.name","value":{"stringValue":"testHost"}},{"key":"service.name","value":{"stringValue":"testService"}}],"droppedAttributesCount":1},"scopeSpans":[{"scope":{"name":"scope name","version":"scope version"},"spans":[{"traceId":"0102030405060708090a0b0c0d0e0f10","spanId":"1112131415161718","traceState":"state","parentSpanId":"1112131415161718","name":"testSpan","kind":3,"startTimeUnixNano":"1684617382541971000","endTimeUnixNano":"1684623646539558000","attributes":[{"key":"string","value":{"stringValue":"value"}},{"key":"bool","value":{"boolValue":true}},{"key":"int","value":{"intValue":"1"}},{"key":"double","value":{"doubleValue":1.1}},{"key":"bytes","value":{"bytesValue":"Zm9v"}},{"key":"array","value":{"arrayValue":{"values":[{"intValue":"1"},{"stringValue":"str"}]}}},{"key":"kvList","value":{"kvlistValue":{"values":[{"key":"int","value":{"intValue":"1"}},{"key":"string","value":{"stringValue":"string"}}]}}}],"droppedAttributesCount":1,"events":[{"timeUnixNano":"1684620382541971000","name":"eventName","attributes":[{"key":"string","value":{"stringValue":"value"}},{"key":"bool","value":{"boolValue":true}},{"key":"int","value":{"intValue":"1"}},{"key":"double","value":{"doubleValue":1.1}},{"key":"bytes","value":{"bytesValue":"Zm9v"}}],"droppedAttributesCount":1}],"droppedEventsCount":1,"links":[{"traceId":"0102030405060708090a0b0c0d0e0f10","spanId":"1112131415161718","traceState":"state","attributes":[{"key":"string","value":{"stringValue":"value"}},{"key":"bool","value":{"boolValue":true}},{"key":"int","value":{"intValue":"1"}},{"key":"double","value":{"doubleValue":1.1}},{"key":"bytes","value":{"bytesValue":"Zm9v"}}],"droppedAttributesCount":1}],"droppedLinksCount":1,"status":{"message":"message","code":1}},{"traceId":"","spanId":"","parentSpanId":"","name":"testSpan2","status":{}}],"schemaUrl":"schemaURL"}],"schemaUrl":"schemaURL"}]}`
+var tracesJSON = `{"resourceSpans":[{"resource":{"attributes":[{"key":"host.name","value":{"stringValue":"testHost"}},{"key":"service.name","value":{"stringValue":"testService"}}],"droppedAttributesCount":1},"scopeSpans":[{"scope":{"name":"scope name","version":"scope version"},"spans":[{"traceId":"0102030405060708090a0b0c0d0e0f10","spanId":"1112131415161718","traceState":"state","parentSpanId":"1112131415161718","flags":1,"name":"testSpan","kind":3,"startTimeUnixNano":"1684617382541971000","endTimeUnixNano":"1684623646539558000","attributes":[{"key":"string","value":{"stringValue":"value"}},{"key":"bool","value":{"boolValue":true}},{"key":"int","value":{"intValue":"1"}},{"key":"double","value":{"doubleValue":1.1}},{"key":"bytes","value":{"bytesValue":"Zm9v"}},{"key":"array","value":{"arrayValue":{"values":[{"intValue":"1"},{"stringValue":"str"}]}}},{"key":"kvList","value":{"kvlistValue":{"values":[{"key":"int","value":{"intValue":"1"}},{"key":"string","value":{"stringValue":"string"}}]}}}],"droppedAttributesCount":1,"events":[{"timeUnixNano":"1684620382541971000","name":"eventName","attributes":[{"key":"string","value":{"stringValue":"value"}},{"key":"bool","value":{"boolValue":true}},{"key":"int","value":{"intValue":"1"}},{"key":"double","value":{"doubleValue":1.1}},{"key":"bytes","value":{"bytesValue":"Zm9v"}}],"droppedAttributesCount":1}],"droppedEventsCount":1,"links":[{"traceId":"0102030405060708090a0b0c0d0e0f10","spanId":"1112131415161718","traceState":"state","attributes":[{"key":"string","value":{"stringValue":"value"}},{"key":"bool","value":{"boolValue":true}},{"key":"int","value":{"intValue":"1"}},{"key":"double","value":{"doubleValue":1.1}},{"key":"bytes","value":{"bytesValue":"Zm9v"}}],"droppedAttributesCount":1,"flags":1}],"droppedLinksCount":1,"status":{"message":"message","code":1}},{"traceId":"","spanId":"","parentSpanId":"","name":"testSpan2","status":{}}],"schemaUrl":"schemaURL"}],"schemaUrl":"schemaURL"}]}`
 
 func TestJSONUnmarshal(t *testing.T) {
 	decoder := &JSONUnmarshaler{}