[WIP] Bad log message fix and refactor

sdk/log/record.go

@@ -27,6 +27,10 @@ var logAttrDropped = sync.OnceFunc(func() {
 	global.Warn("limit reached: dropping log Record attributes")
 })
 
+var logKeyValuePairDropped = sync.OnceFunc(func() {
+	global.Warn("key duplication: dropping key-value pair")
+})
+
 // indexPool is a pool of index maps used for de-duplication.
 var indexPool = sync.Pool{
 	New: func() any { return make(map[string]int) },
@@ -97,12 +101,10 @@ type Record struct {
 }
 
 func (r *Record) addDropped(n int) {
-	logAttrDropped()
 	r.dropped += n
 }
 
 func (r *Record) setDropped(n int) {
-	logAttrDropped()
 	r.dropped = n
 }
 
@@ -192,11 +194,15 @@ func (r *Record) AddAttributes(attrs ...log.KeyValue) {
 	if n == 0 {
 		// Avoid the more complex duplicate map lookups below.
 		var drop int
-		attrs, drop = dedup(attrs)
-		r.setDropped(drop)
+		attrs = dedup(attrs)
+		r.setDropped(0)
 
 		attrs, drop = head(attrs, r.attributeCountLimit)
+
 		r.addDropped(drop)
+		if drop > 0 {
+			logAttrDropped()
+		}
 
 		r.addAttrs(attrs)
 		return
@@ -221,15 +227,15 @@ func (r *Record) AddAttributes(attrs ...log.KeyValue) {
 		// Last-value-wins for any duplicates in attrs.
 		idx, found := uIndex[a.Key]
 		if found {
-			r.addDropped(1)
+			logKeyValuePairDropped()
 			unique[idx] = a
 			continue
 		}
 
 		idx, found = rIndex[a.Key]
 		if found {
 			// New attrs overwrite any existing with the same key.
-			r.addDropped(1)
+			logKeyValuePairDropped()
 			if idx < 0 {
 				r.front[-(idx + 1)] = a
 			} else {
@@ -249,7 +255,12 @@ func (r *Record) AddAttributes(attrs ...log.KeyValue) {
 		// Do not use head(attrs, r.attributeCountLimit - n) here. If
 		// (r.attributeCountLimit - n) <= 0 attrs needs to be emptied.
 		last := max(0, r.attributeCountLimit-n)
-		r.addDropped(len(attrs) - last)
+		dropped := len(attrs) - last
+		r.addDropped(dropped)
+
+		if dropped > 0 {
+			logAttrDropped()
+		}
 		attrs = attrs[:last]
 	}
 
@@ -297,12 +308,16 @@ func (r *Record) addAttrs(attrs []log.KeyValue) {
 // SetAttributes sets (and overrides) attributes to the log record.
 func (r *Record) SetAttributes(attrs ...log.KeyValue) {
 	var drop int
-	attrs, drop = dedup(attrs)
-	r.setDropped(drop)
+	attrs = dedup(attrs)
+	r.setDropped(0)
 
 	attrs, drop = head(attrs, r.attributeCountLimit)
 	r.addDropped(drop)
 
+	if drop > 0 {
+		logAttrDropped()
+	}
+
 	r.nFront = 0
 	var i int
 	for i = 0; i < len(attrs) && r.nFront < len(r.front); i++ {
@@ -327,22 +342,22 @@ func head(kvs []log.KeyValue, n int) (out []log.KeyValue, dropped int) {
 }
 
 // dedup deduplicates kvs front-to-back with the last value saved.
-func dedup(kvs []log.KeyValue) (unique []log.KeyValue, dropped int) {
+func dedup(kvs []log.KeyValue) (unique []log.KeyValue) {
 	index := getIndex()
 	defer putIndex(index)
 
 	unique = kvs[:0] // Use the same underlying array as kvs.
 	for _, a := range kvs {
 		idx, found := index[a.Key]
 		if found {
-			dropped++
 			unique[idx] = a
+			logKeyValuePairDropped()
 		} else {
 			unique = append(unique, a)
 			index[a.Key] = len(unique) - 1
 		}
 	}
-	return unique, dropped
+	return unique
 }
 
 // AttributesLen returns the number of attributes in the log record.
@@ -428,8 +443,8 @@ func (r *Record) applyValueLimits(val log.Value) log.Value {
 	case log.KindMap:
 		// Deduplicate then truncate. Do not do at the same time to avoid
 		// wasted truncation operations.
-		kvs, dropped := dedup(val.AsMap())
-		r.addDropped(dropped)
+		kvs := dedup(val.AsMap())
+
 		for i := range kvs {
 			kvs[i] = r.applyAttrLimits(kvs[i])
 		}

sdk/log/record_test.go

@@ -204,12 +204,12 @@ func TestRecordClone(t *testing.T) {
 }
 
 func TestRecordDroppedAttributes(t *testing.T) {
-	orig := logAttrDropped
-	t.Cleanup(func() { logAttrDropped = orig })
+	orig := logKeyValuePairDropped
+	t.Cleanup(func() { logKeyValuePairDropped = orig })
 
 	for i := 1; i < attributesInlineCount*5; i++ {
 		var called bool
-		logAttrDropped = func() { called = true }
+		logKeyValuePairDropped = func() { called = true }
 
 		r := new(Record)
 		r.attributeCountLimit = 1