Capture Log Attributes in the Agent

v3/newrelic/attributes_from_internal.go

@@ -5,10 +5,12 @@ package newrelic
 
 import (
 	"bytes"
+	"encoding/json"
 	"fmt"
 	"math"
 	"net/http"
 	"net/url"
+	"reflect"
 	"sort"
 	"strconv"
 	"strings"
@@ -19,6 +21,9 @@ const (
 	// listed as span attributes to simplify code. It is not listed in the
 	// public attributes.go file for this reason to prevent confusion.
 	spanAttributeQueryParameters = "query_parameters"
+
+	// The collector can only allow attributes to be a maximum of 256 bytes
+	maxAttributeLengthBytes = 256
 )
 
 var (
@@ -452,6 +457,9 @@ func addUserAttribute(a *attributes, key string, val interface{}, d destinationS
 func writeAttributeValueJSON(w *jsonFieldsWriter, key string, val interface{}) {
 	switch v := val.(type) {
 	case string:
+		if len(v) > maxAttributeLengthBytes {
+			v = v[:maxAttributeLengthBytes]
+		}
 		w.stringField(key, v)
 	case bool:
 		if v {
@@ -486,7 +494,17 @@ func writeAttributeValueJSON(w *jsonFieldsWriter, key string, val interface{}) {
 	case float64:
 		w.floatField(key, v)
 	default:
-		w.stringField(key, fmt.Sprintf("%T", v))
+		// attempt to construct a JSON string
+		kind := reflect.ValueOf(v).Kind()
+		if kind == reflect.Struct || kind == reflect.Map || kind == reflect.Slice || kind == reflect.Array {
+			bytes, _ := json.Marshal(v)
+			if len(bytes) > maxAttributeLengthBytes {
+				bytes = bytes[:maxAttributeLengthBytes]
+			}
+			w.stringField(key, string(bytes))
+		} else {
+			w.stringField(key, fmt.Sprintf("%T", v))
+		}
 	}
 }
 

v3/newrelic/harvest_test.go

@@ -315,6 +315,7 @@ func TestHarvestLogEventsReady(t *testing.T) {
 	})
 
 	logEvent := logEvent{
+		nil,
 		0.5,
 		123456,
 		"INFO",
@@ -576,6 +577,7 @@ func TestMergeFailedHarvest(t *testing.T) {
 	}, 0)
 
 	logEvent := logEvent{
+		nil,
 		0.5,
 		123456,
 		"INFO",

v3/newrelic/log_event.go

@@ -19,6 +19,7 @@ const (
 )
 
 type logEvent struct {
+	atributes map[string]any
 	priority  priority
 	timestamp int64
 	severity  string
@@ -28,10 +29,15 @@ type logEvent struct {
 }
 
 // LogData contains data fields that are needed to generate log events.
+// Note: if you are passing a struct, map, slice, or array as an attribute, try to pass it as a JSON string generated by the logging framework if possible.
+// The collector can parse that into an object on New Relic's side.
+// This is preferable because the json.Marshal method used in the agent to create the string log JSON is usually less efficient than the tools built into
+// logging products for creating stringified JSON for complex objects and data structures.
 type LogData struct {
-	Timestamp int64  // Optional: Unix Millisecond Timestamp; A timestamp will be generated if unset
-	Severity  string // Optional: Severity of log being consumed
-	Message   string // Optional: Message of log being consumed; Maximum size: 32768 Bytes.
+	Timestamp  int64          // Optional: Unix Millisecond Timestamp; A timestamp will be generated if unset
+	Severity   string         // Optional: Severity of log being consumed
+	Message    string         // Optional: Message of log being consumed; Maximum size: 32768 Bytes.
+	Attributes map[string]any // Optional: a key value pair with a string key, and any value. This can be used for categorizing logs in the UI.
 }
 
 // writeJSON prepares JSON in the format expected by the collector.
@@ -51,6 +57,14 @@ func (e *logEvent) WriteJSON(buf *bytes.Buffer) {
 	w.needsComma = false
 	buf.WriteByte(',')
 	w.intField(logcontext.LogTimestampFieldName, e.timestamp)
+	if e.atributes != nil && len(e.atributes) > 0 {
+		buf.WriteString(`,"attributes":{`)
+		w := jsonFieldsWriter{buf: buf}
+		for key, val := range e.atributes {
+			writeAttributeValueJSON(&w, key, val)
+		}
+		buf.WriteByte('}')
+	}
 	buf.WriteByte('}')
 }
 
@@ -88,6 +102,7 @@ func (data *LogData) toLogEvent() (logEvent, error) {
 		message:   data.Message,
 		severity:  data.Severity,
 		timestamp: data.Timestamp,
+		atributes: data.Attributes,
 	}
 
 	return event, nil

v3/newrelic/log_events.go

@@ -60,7 +60,7 @@ type logEventHeap []logEvent
 
 // TODO: when go 1.18 becomes the minimum supported version, re-write to make a generic heap implementation
 // for all event heaps, to de-duplicate this code
-//func (events *logEvents)
+// func (events *logEvents)
 func (h logEventHeap) Len() int           { return len(h) }
 func (h logEventHeap) Less(i, j int) bool { return h[i].priority.isLowerPriority(h[j].priority) }
 func (h logEventHeap) Swap(i, j int)      { h[i], h[j] = h[j], h[i] }

v3/newrelic/log_events_test.go

@@ -36,19 +36,20 @@ func loggingConfigEnabled(limit int) loggingConfig {
 	}
 }
 
-func sampleLogEvent(priority priority, severity, message string) *logEvent {
+func sampleLogEvent(priority priority, severity, message string, attributes map[string]any) *logEvent {
 	return &logEvent{
 		priority:  priority,
 		severity:  severity,
 		message:   message,
+		atributes: attributes,
 		timestamp: 123456,
 	}
 }
 
 func TestBasicLogEvents(t *testing.T) {
 	events := newLogEvents(testCommonAttributes, loggingConfigEnabled(5))
-	events.Add(sampleLogEvent(0.5, infoLevel, "message1"))
-	events.Add(sampleLogEvent(0.5, infoLevel, "message2"))
+	events.Add(sampleLogEvent(0.5, infoLevel, "message1", nil))
+	events.Add(sampleLogEvent(0.5, infoLevel, "message2", nil))
 
 	json, err := events.CollectorJSON(agentRunID)
 	if nil != err {
@@ -70,6 +71,53 @@ func TestBasicLogEvents(t *testing.T) {
 	}
 }
 
+type testStruct struct {
+	A string
+	B int
+	C c
+}
+
+type c struct {
+	D string
+}
+
+func TestBasicLogEventWithAttributes(t *testing.T) {
+	st := testStruct{
+		A: "a",
+		B: 1,
+		C: c{"hello"},
+	}
+
+	events := newLogEvents(testCommonAttributes, loggingConfigEnabled(5))
+	events.Add(sampleLogEvent(0.5, infoLevel, "message1", map[string]any{"two": "hi"}))
+	events.Add(sampleLogEvent(0.5, infoLevel, "message2", map[string]any{"struct": st}))
+	events.Add(sampleLogEvent(0.5, infoLevel, "message3", map[string]any{"map": map[string]string{"hi": "hello"}}))
+	events.Add(sampleLogEvent(0.5, infoLevel, "message4", map[string]any{"slice": []string{"hi", "hello", "test"}}))
+	events.Add(sampleLogEvent(0.5, infoLevel, "message5", map[string]any{"array": [2]int{1, 2}}))
+
+	json, err := events.CollectorJSON(agentRunID)
+	if nil != err {
+		t.Fatal(err)
+	}
+
+	expected := commonJSON +
+		`{"level":"INFO","message":"message1","timestamp":123456,"attributes":{"two":"hi"}},` +
+		`{"level":"INFO","message":"message2","timestamp":123456,"attributes":{"struct":"{\"A\":\"a\",\"B\":1,\"C\":{\"D\":\"hello\"}}"}},` +
+		`{"level":"INFO","message":"message3","timestamp":123456,"attributes":{"map":"{\"hi\":\"hello\"}"}},` +
+		`{"level":"INFO","message":"message4","timestamp":123456,"attributes":{"slice":"[\"hi\",\"hello\",\"test\"]"}},` +
+		`{"level":"INFO","message":"message5","timestamp":123456,"attributes":{"array":"[1,2]"}}]}]`
+
+	if string(json) != expected {
+		t.Error("actual not equal to expected:\n", string(json), "\n", expected)
+	}
+	if events.numSeen != 5 {
+		t.Error(events.numSeen)
+	}
+	if events.NumSaved() != 5 {
+		t.Error(events.NumSaved())
+	}
+}
+
 func TestEmptyLogEvents(t *testing.T) {
 	events := newLogEvents(testCommonAttributes, loggingConfigEnabled(10))
 	json, err := events.CollectorJSON(agentRunID)
@@ -79,10 +127,10 @@ func TestEmptyLogEvents(t *testing.T) {
 	if nil != json {
 		t.Error(string(json))
 	}
-	if 0 != events.numSeen {
+	if events.numSeen != 0 {
 		t.Error(events.numSeen)
 	}
-	if 0 != events.NumSaved() {
+	if events.NumSaved() != 0 {
 		t.Error(events.NumSaved())
 	}
 }
@@ -91,12 +139,12 @@ func TestEmptyLogEvents(t *testing.T) {
 func TestSamplingLogEvents(t *testing.T) {
 	events := newLogEvents(testCommonAttributes, loggingConfigEnabled(3))
 
-	events.Add(sampleLogEvent(0.999999, infoLevel, "a"))
-	events.Add(sampleLogEvent(0.1, infoLevel, "b"))
-	events.Add(sampleLogEvent(0.9, infoLevel, "c"))
-	events.Add(sampleLogEvent(0.2, infoLevel, "d"))
-	events.Add(sampleLogEvent(0.8, infoLevel, "e"))
-	events.Add(sampleLogEvent(0.3, infoLevel, "f"))
+	events.Add(sampleLogEvent(0.999999, infoLevel, "a", nil))
+	events.Add(sampleLogEvent(0.1, infoLevel, "b", nil))
+	events.Add(sampleLogEvent(0.9, infoLevel, "c", nil))
+	events.Add(sampleLogEvent(0.2, infoLevel, "d", nil))
+	events.Add(sampleLogEvent(0.8, infoLevel, "e", nil))
+	events.Add(sampleLogEvent(0.3, infoLevel, "f", nil))
 
 	json, err := events.CollectorJSON(agentRunID)
 	if nil != err {
@@ -141,14 +189,14 @@ func TestMergeFullLogEvents(t *testing.T) {
 	e1 := newLogEvents(testCommonAttributes, loggingConfigEnabled(2))
 	e2 := newLogEvents(testCommonAttributes, loggingConfigEnabled(3))
 
-	e1.Add(sampleLogEvent(0.1, infoLevel, "a"))
-	e1.Add(sampleLogEvent(0.15, infoLevel, "b"))
-	e1.Add(sampleLogEvent(0.25, infoLevel, "c"))
+	e1.Add(sampleLogEvent(0.1, infoLevel, "a", nil))
+	e1.Add(sampleLogEvent(0.15, infoLevel, "b", nil))
+	e1.Add(sampleLogEvent(0.25, infoLevel, "c", nil))
 
-	e2.Add(sampleLogEvent(0.06, infoLevel, "d"))
-	e2.Add(sampleLogEvent(0.12, infoLevel, "e"))
-	e2.Add(sampleLogEvent(0.18, infoLevel, "f"))
-	e2.Add(sampleLogEvent(0.24, infoLevel, "g"))
+	e2.Add(sampleLogEvent(0.06, infoLevel, "d", nil))
+	e2.Add(sampleLogEvent(0.12, infoLevel, "e", nil))
+	e2.Add(sampleLogEvent(0.18, infoLevel, "f", nil))
+	e2.Add(sampleLogEvent(0.24, infoLevel, "g", nil))
 
 	e1.Merge(e2)
 	json, err := e1.CollectorJSON(agentRunID)
@@ -176,14 +224,14 @@ func TestLogEventMergeFailedSuccess(t *testing.T) {
 	e1 := newLogEvents(testCommonAttributes, loggingConfigEnabled(2))
 	e2 := newLogEvents(testCommonAttributes, loggingConfigEnabled(3))
 
-	e1.Add(sampleLogEvent(0.1, infoLevel, "a"))
-	e1.Add(sampleLogEvent(0.15, infoLevel, "b"))
-	e1.Add(sampleLogEvent(0.25, infoLevel, "c"))
+	e1.Add(sampleLogEvent(0.1, infoLevel, "a", nil))
+	e1.Add(sampleLogEvent(0.15, infoLevel, "b", nil))
+	e1.Add(sampleLogEvent(0.25, infoLevel, "c", nil))
 
-	e2.Add(sampleLogEvent(0.06, infoLevel, "d"))
-	e2.Add(sampleLogEvent(0.12, infoLevel, "e"))
-	e2.Add(sampleLogEvent(0.18, infoLevel, "f"))
-	e2.Add(sampleLogEvent(0.24, infoLevel, "g"))
+	e2.Add(sampleLogEvent(0.06, infoLevel, "d", nil))
+	e2.Add(sampleLogEvent(0.12, infoLevel, "e", nil))
+	e2.Add(sampleLogEvent(0.18, infoLevel, "f", nil))
+	e2.Add(sampleLogEvent(0.24, infoLevel, "g", nil))
 
 	e1.mergeFailed(e2)
 
@@ -214,14 +262,14 @@ func TestLogEventMergeFailedLimitReached(t *testing.T) {
 	e1 := newLogEvents(testCommonAttributes, loggingConfigEnabled(2))
 	e2 := newLogEvents(testCommonAttributes, loggingConfigEnabled(3))
 
-	e1.Add(sampleLogEvent(0.1, infoLevel, "a"))
-	e1.Add(sampleLogEvent(0.15, infoLevel, "b"))
-	e1.Add(sampleLogEvent(0.25, infoLevel, "c"))
+	e1.Add(sampleLogEvent(0.1, infoLevel, "a", nil))
+	e1.Add(sampleLogEvent(0.15, infoLevel, "b", nil))
+	e1.Add(sampleLogEvent(0.25, infoLevel, "c", nil))
 
-	e2.Add(sampleLogEvent(0.06, infoLevel, "d"))
-	e2.Add(sampleLogEvent(0.12, infoLevel, "e"))
-	e2.Add(sampleLogEvent(0.18, infoLevel, "f"))
-	e2.Add(sampleLogEvent(0.24, infoLevel, "g"))
+	e2.Add(sampleLogEvent(0.06, infoLevel, "d", nil))
+	e2.Add(sampleLogEvent(0.12, infoLevel, "e", nil))
+	e2.Add(sampleLogEvent(0.18, infoLevel, "f", nil))
+	e2.Add(sampleLogEvent(0.24, infoLevel, "g", nil))
 
 	e2.failedHarvests = failedEventsAttemptsLimit
 
@@ -253,7 +301,7 @@ func TestLogEventsSplitFull(t *testing.T) {
 	events := newLogEvents(testCommonAttributes, loggingConfigEnabled(10))
 	for i := 0; i < 15; i++ {
 		priority := priority(float32(i) / 10.0)
-		events.Add(sampleLogEvent(priority, "INFO", fmt.Sprint(priority)))
+		events.Add(sampleLogEvent(priority, "INFO", fmt.Sprint(priority), nil))
 	}
 	// Test that the capacity cannot exceed the max.
 	if 10 != events.capacity() {
@@ -292,7 +340,7 @@ func TestLogEventsSplitNotFullOdd(t *testing.T) {
 	events := newLogEvents(testCommonAttributes, loggingConfigEnabled(10))
 	for i := 0; i < 7; i++ {
 		priority := priority(float32(i) / 10.0)
-		events.Add(sampleLogEvent(priority, "INFO", fmt.Sprint(priority)))
+		events.Add(sampleLogEvent(priority, "INFO", fmt.Sprint(priority), nil))
 	}
 	e1, e2 := events.split()
 	j1, err1 := e1.CollectorJSON(agentRunID)
@@ -322,7 +370,7 @@ func TestLogEventsSplitNotFullEven(t *testing.T) {
 	events := newLogEvents(testCommonAttributes, loggingConfigEnabled(10))
 	for i := 0; i < 8; i++ {
 		priority := priority(float32(i) / 10.0)
-		events.Add(sampleLogEvent(priority, "INFO", fmt.Sprint(priority)))
+		events.Add(sampleLogEvent(priority, "INFO", fmt.Sprint(priority), nil))
 	}
 	e1, e2 := events.split()
 	j1, err1 := e1.CollectorJSON(agentRunID)
@@ -356,7 +404,7 @@ func TestLogEventsZeroCapacity(t *testing.T) {
 	if 0 != events.NumSeen() || 0 != events.NumSaved() || 0 != events.capacity() {
 		t.Error(events.NumSeen(), events.NumSaved(), events.capacity())
 	}
-	events.Add(sampleLogEvent(0.5, "INFO", "TEST"))
+	events.Add(sampleLogEvent(0.5, "INFO", "TEST", nil))
 	if 1 != events.NumSeen() || 0 != events.NumSaved() || 0 != events.capacity() {
 		t.Error(events.NumSeen(), events.NumSaved(), events.capacity())
 	}
@@ -375,7 +423,7 @@ func TestLogEventCollectionDisabled(t *testing.T) {
 	if 0 != events.NumSeen() || 0 != len(events.severityCount) || 0 != events.NumSaved() || 5 != events.capacity() {
 		t.Error(events.NumSeen(), len(events.severityCount), events.NumSaved(), events.capacity())
 	}
-	events.Add(sampleLogEvent(0.5, "INFO", "TEST"))
+	events.Add(sampleLogEvent(0.5, "INFO", "TEST", nil))
 	if 1 != events.NumSeen() || 1 != len(events.severityCount) || 0 != events.NumSaved() || 5 != events.capacity() {
 		t.Error(events.NumSeen(), len(events.severityCount), events.NumSaved(), events.capacity())
 	}
@@ -467,6 +515,7 @@ func BenchmarkRecordLoggingMetrics(b *testing.B) {
 
 	for i := 0; i < internal.MaxLogEvents; i++ {
 		logEvent := logEvent{
+			nil,
 			newPriority(),
 			123456,
 			"INFO",