[receiver/libhoney] Libhoney receiver trace signal (#36902)

#### Description

This PR is the implementation for the traces signal related to the new
libhoney receiver.

<!-- Issue number (e.g. #1234) or full URL to issue, if applicable. -->
#### Link to tracking issue

#36693

Author: mterhar

.chloggen/traces-for-libhoneyreceiver.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: libhoneyreceiver
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Implement trace signal for libhoney receiver
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [36693]
+
+# (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:
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# 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: [user]

receiver/libhoneyreceiver/go.mod

@@ -18,6 +18,7 @@ require (
 	go.opentelemetry.io/collector/receiver v0.116.0
 	go.opentelemetry.io/collector/receiver/receivertest v0.116.0
 	go.opentelemetry.io/collector/semconv v0.116.0
+	go.opentelemetry.io/otel/trace v1.32.0
 	go.uber.org/goleak v1.3.0
 	go.uber.org/zap v1.27.0
 	google.golang.org/genproto/googleapis/rpc v0.0.0-20241015192408-796eee8c2d53
@@ -68,7 +69,6 @@ require (
 	go.opentelemetry.io/otel/metric v1.32.0 // indirect
 	go.opentelemetry.io/otel/sdk v1.32.0 // indirect
 	go.opentelemetry.io/otel/sdk/metric v1.32.0 // indirect
-	go.opentelemetry.io/otel/trace v1.32.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
 	golang.org/x/net v0.32.0 // indirect
 	golang.org/x/sys v0.28.0 // indirect

receiver/libhoneyreceiver/internal/libhoneyevent/libhoneyevent.go

@@ -4,15 +4,21 @@
 package libhoneyevent // import "github.com/open-telemetry/opentelemetry-collector-contrib/receiver/libhoneyreceiver/internal/libhoneyevent"
 
 import (
+	"crypto/rand"
+	"encoding/binary"
+	"encoding/hex"
 	"encoding/json"
 	"errors"
 	"fmt"
+	"hash/fnv"
 	"slices"
+	"strings"
 	"time"
 
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	"go.opentelemetry.io/collector/pdata/plog"
 	"go.opentelemetry.io/collector/pdata/ptrace"
+	trc "go.opentelemetry.io/otel/trace"
 	"go.uber.org/zap"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/receiver/libhoneyreceiver/internal/eventtime"
@@ -87,8 +93,29 @@ func (l *LibhoneyEvent) DebugString() string {
 }
 
 // SignalType returns the type of signal this event represents. Only log is implemented for now.
-func (l *LibhoneyEvent) SignalType() (string, error) {
-	return "log", nil
+func (l *LibhoneyEvent) SignalType(logger zap.Logger) string {
+	if sig, ok := l.Data["meta.signal_type"]; ok {
+		switch sig {
+		case "trace":
+			if atype, ok := l.Data["meta.annotation_type"]; ok {
+				if atype == "span_event" {
+					return "span_event"
+				} else if atype == "link" {
+					return "span_link"
+				}
+				logger.Warn("invalid annotation type", zap.String("meta.annotation_type", atype.(string)))
+				return "span"
+			}
+			return "span"
+		case "log":
+			return "log"
+		default:
+			logger.Warn("invalid meta.signal_type", zap.String("meta.signal_type", sig.(string)))
+			return "log"
+		}
+	}
+	logger.Warn("missing meta.signal_type and meta.annotation_type")
+	return "log"
 }
 
 // GetService returns the service name from the event or the dataset name if no service name is found.
@@ -126,6 +153,36 @@ func (l *LibhoneyEvent) GetScope(fields FieldMapConfig, seen *ScopeHistory, serv
 	return "libhoney.receiver", errors.New("library name not found")
 }
 
+func spanIDFrom(s string) trc.SpanID {
+	hash := fnv.New64a()
+	hash.Write([]byte(s))
+	n := hash.Sum64()
+	sid := trc.SpanID{}
+	binary.LittleEndian.PutUint64(sid[:], n)
+	return sid
+}
+
+func traceIDFrom(s string) trc.TraceID {
+	hash := fnv.New64a()
+	hash.Write([]byte(s))
+	n1 := hash.Sum64()
+	hash.Write([]byte(s))
+	n2 := hash.Sum64()
+	tid := trc.TraceID{}
+	binary.LittleEndian.PutUint64(tid[:], n1)
+	binary.LittleEndian.PutUint64(tid[8:], n2)
+	return tid
+}
+
+func generateAnId(length int) []byte {
+	token := make([]byte, length)
+	_, err := rand.Read(token)
+	if err != nil {
+		return []byte{}
+	}
+	return token
+}
+
 // SimpleScope is a simple struct to hold the scope data
 type SimpleScope struct {
 	ServiceName    string
@@ -198,3 +255,130 @@ func (l *LibhoneyEvent) ToPLogRecord(newLog *plog.LogRecord, alreadyUsedFields *
 	}
 	return nil
 }
+
+// GetParentID returns the parent id from the event or an error if it's not found
+func (l *LibhoneyEvent) GetParentID(fieldName string) (trc.SpanID, error) {
+	if pid, ok := l.Data[fieldName]; ok {
+		pid := strings.ReplaceAll(pid.(string), "-", "")
+		pidByteArray, err := hex.DecodeString(pid)
+		if err == nil {
+			if len(pidByteArray) == 32 {
+				pidByteArray = pidByteArray[8:24]
+			} else if len(pidByteArray) >= 16 {
+				pidByteArray = pidByteArray[0:16]
+			}
+			return trc.SpanID(pidByteArray), nil
+		}
+		return trc.SpanID{}, errors.New("parent id is not a valid span id")
+	}
+	return trc.SpanID{}, errors.New("parent id not found")
+}
+
+// ToPTraceSpan converts a LibhoneyEvent to a Pdata Span
+func (l *LibhoneyEvent) ToPTraceSpan(newSpan *ptrace.Span, alreadyUsedFields *[]string, cfg FieldMapConfig, logger zap.Logger) error {
+	time_ns := l.MsgPackTimestamp.UnixNano()
+	logger.Debug("processing trace with", zap.Int64("timestamp", time_ns))
+
+	var parent_id trc.SpanID
+	if pid, ok := l.Data[cfg.Attributes.ParentID]; ok {
+		parent_id = spanIDFrom(pid.(string))
+		newSpan.SetParentSpanID(pcommon.SpanID(parent_id))
+	}
+
+	duration_ms := 0.0
+	for _, df := range cfg.Attributes.DurationFields {
+		if duration, okay := l.Data[df]; okay {
+			duration_ms = duration.(float64)
+			break
+		}
+	}
+	end_timestamp := time_ns + (int64(duration_ms) * 1000000)
+
+	if tid, ok := l.Data[cfg.Attributes.TraceID]; ok {
+		tid := strings.ReplaceAll(tid.(string), "-", "")
+		tidByteArray, err := hex.DecodeString(tid)
+		if err == nil {
+			if len(tidByteArray) >= 32 {
+				tidByteArray = tidByteArray[0:32]
+			}
+			newSpan.SetTraceID(pcommon.TraceID(tidByteArray))
+		} else {
+			newSpan.SetTraceID(pcommon.TraceID(traceIDFrom(tid)))
+		}
+	} else {
+		newSpan.SetTraceID(pcommon.TraceID(generateAnId(32)))
+	}
+
+	if sid, ok := l.Data[cfg.Attributes.SpanID]; ok {
+		sid := strings.ReplaceAll(sid.(string), "-", "")
+		sidByteArray, err := hex.DecodeString(sid)
+		if err == nil {
+			if len(sidByteArray) == 32 {
+				sidByteArray = sidByteArray[8:24]
+			} else if len(sidByteArray) >= 16 {
+				sidByteArray = sidByteArray[0:16]
+			}
+			newSpan.SetSpanID(pcommon.SpanID(sidByteArray))
+		} else {
+			newSpan.SetSpanID(pcommon.SpanID(spanIDFrom(sid)))
+		}
+	} else {
+		newSpan.SetSpanID(pcommon.SpanID(generateAnId(16)))
+	}
+
+	newSpan.SetStartTimestamp(pcommon.Timestamp(time_ns))
+	newSpan.SetEndTimestamp(pcommon.Timestamp(end_timestamp))
+
+	if spanName, ok := l.Data[cfg.Attributes.Name]; ok {
+		newSpan.SetName(spanName.(string))
+	}
+	if spanStatusMessge, ok := l.Data["status_message"]; ok {
+		newSpan.Status().SetMessage(spanStatusMessge.(string))
+	}
+	newSpan.Status().SetCode(ptrace.StatusCodeUnset)
+
+	if _, ok := l.Data[cfg.Attributes.Error]; ok {
+		newSpan.Status().SetCode(ptrace.StatusCodeError)
+	}
+
+	if spanKind, ok := l.Data[cfg.Attributes.SpanKind]; ok {
+		switch spanKind.(string) {
+		case "server":
+			newSpan.SetKind(ptrace.SpanKindServer)
+		case "client":
+			newSpan.SetKind(ptrace.SpanKindClient)
+		case "producer":
+			newSpan.SetKind(ptrace.SpanKindProducer)
+		case "consumer":
+			newSpan.SetKind(ptrace.SpanKindConsumer)
+		case "internal":
+			newSpan.SetKind(ptrace.SpanKindInternal)
+		default:
+			newSpan.SetKind(ptrace.SpanKindUnspecified)
+		}
+	}
+
+	newSpan.Attributes().PutInt("SampleRate", int64(l.Samplerate))
+
+	for k, v := range l.Data {
+		if slices.Contains(*alreadyUsedFields, k) {
+			continue
+		}
+		switch v := v.(type) {
+		case string:
+			newSpan.Attributes().PutStr(k, v)
+		case int:
+			newSpan.Attributes().PutInt(k, int64(v))
+		case int64, int16, int32:
+			intv := v.(int64)
+			newSpan.Attributes().PutInt(k, intv)
+		case float64:
+			newSpan.Attributes().PutDouble(k, v)
+		case bool:
+			newSpan.Attributes().PutBool(k, v)
+		default:
+			logger.Warn("Span data type issue", zap.String("trace.trace_id", newSpan.TraceID().String()), zap.String("trace.span_id", newSpan.SpanID().String()), zap.String("key", k))
+		}
+	}
+	return nil
+}

receiver/libhoneyreceiver/internal/libhoneyevent/libhoneyevent_test.go

@@ -12,6 +12,7 @@ import (
 	"github.com/stretchr/testify/require"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	"go.opentelemetry.io/collector/pdata/plog"
+	"go.opentelemetry.io/collector/pdata/ptrace"
 	"go.uber.org/zap"
 )
 
@@ -292,3 +293,109 @@ func TestLibhoneyEvent_GetScope(t *testing.T) {
 		})
 	}
 }
+
+func TestToPTraceSpan(t *testing.T) {
+	now := time.Now()
+	tests := []struct {
+		name    string
+		event   LibhoneyEvent
+		want    func(ptrace.Span)
+		wantErr bool
+	}{
+		{
+			name: "basic span conversion",
+			event: LibhoneyEvent{
+				Time:             now.Format(time.RFC3339),
+				MsgPackTimestamp: &now,
+				Data: map[string]any{
+					"name":           "test-span",
+					"trace.span_id":  "1234567890abcdef",
+					"trace.trace_id": "1234567890abcdef1234567890abcdef",
+					"duration_ms":    100.0,
+					"error":          true,
+					"status_message": "error message",
+					"kind":           "server",
+					"string_attr":    "value",
+					"int_attr":       42,
+					"bool_attr":      true,
+				},
+				Samplerate: 1,
+			},
+			want: func(s ptrace.Span) {
+				s.SetName("test-span")
+				s.SetSpanID([8]byte{0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef})
+				s.SetTraceID([16]byte{0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef, 0x12, 0x34, 0x56, 0x78, 0x90, 0xab, 0xcd, 0xef})
+				s.SetStartTimestamp(pcommon.NewTimestampFromTime(now))
+				s.SetEndTimestamp(pcommon.NewTimestampFromTime(now.Add(100 * time.Millisecond)))
+				s.Status().SetCode(ptrace.StatusCodeError)
+				s.Status().SetMessage("error message")
+				s.SetKind(ptrace.SpanKindServer)
+				s.Attributes().PutStr("string_attr", "value")
+				s.Attributes().PutInt("int_attr", 42)
+				s.Attributes().PutBool("bool_attr", true)
+			},
+		},
+	}
+
+	alreadyUsedFields := []string{"name", "trace.span_id", "trace.trace_id", "duration_ms", "status.code", "status.message", "kind"}
+	testCfg := FieldMapConfig{
+		Attributes: AttributesConfig{
+			Name:           "name",
+			TraceID:        "trace.trace_id",
+			SpanID:         "trace.span_id",
+			ParentID:       "trace.parent_id",
+			Error:          "error",
+			SpanKind:       "kind",
+			DurationFields: []string{"duration_ms"},
+		},
+		Resources: ResourcesConfig{
+			ServiceName: "service.name",
+		},
+		Scopes: ScopesConfig{
+			LibraryName:    "library.name",
+			LibraryVersion: "library.version",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			span := ptrace.NewSpan()
+			err := tt.event.ToPTraceSpan(&span, &alreadyUsedFields, testCfg, *zap.NewNop())
+
+			if tt.wantErr {
+				assert.Error(t, err)
+				return
+			}
+
+			require.NoError(t, err)
+			if tt.want != nil {
+				want := ptrace.NewSpan()
+				tt.want(want)
+
+				// Check basic fields
+				assert.Equal(t, want.Name(), span.Name())
+				assert.Equal(t, want.SpanID(), span.SpanID())
+				assert.Equal(t, want.TraceID(), span.TraceID())
+				assert.Equal(t, want.StartTimestamp(), span.StartTimestamp())
+				assert.Equal(t, want.EndTimestamp(), span.EndTimestamp())
+				assert.Equal(t, want.Kind(), span.Kind())
+
+				// Check status
+				assert.Equal(t, want.Status().Code(), span.Status().Code())
+				assert.Equal(t, want.Status().Message(), span.Status().Message())
+
+				// Check attributes
+				want.Attributes().Range(func(k string, v pcommon.Value) bool {
+					got, ok := span.Attributes().Get(k)
+					assert.True(t, ok, "missing attribute %s", k)
+					assert.Equal(t, v.Type(), got.Type(), "wrong type for attribute %s", k)
+					assert.Equal(t, v, got, "wrong value for attribute %s", k)
+					return true
+				})
+
+				// Verify no fewer attributes, extras are expected
+				assert.LessOrEqual(t, want.Attributes().Len(), span.Attributes().Len())
+			}
+		})
+	}
+}