fixup! Update go.mod and go.sum (#48)

internal/httplog/benchmark_test.go

@@ -0,0 +1,270 @@
+package httplog
+
+import (
+	"bytes"
+	"encoding/json"
+	"io"
+	"net/http"
+	"testing"
+)
+
+// BenchmarkLoggerLog benchmarks the Log function with sync.Pool
+func BenchmarkLoggerLog(b *testing.B) {
+	l := &Logger{
+		forwardID:  "benchmark",
+		maxBodyLen: 1024,
+		output:     io.Discard,
+	}
+
+	entry := Entry{
+		Direction:  "request",
+		RequestID:  "req-123",
+		Method:     "POST",
+		Path:       "/api/users",
+		BodySize:   256,
+		Body:       `{"name":"test user","email":"test@example.com","data":"some payload data here"}`,
+		StatusCode: 200,
+		LatencyMs:  42,
+	}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = l.Log(entry)
+	}
+}
+
+// BenchmarkLoggerLogNoPool simulates logging without sync.Pool
+func BenchmarkLoggerLogNoPool(b *testing.B) {
+	l := &Logger{
+		forwardID:  "benchmark",
+		maxBodyLen: 1024,
+		output:     io.Discard,
+	}
+
+	entry := Entry{
+		Direction:  "request",
+		RequestID:  "req-123",
+		Method:     "POST",
+		Path:       "/api/users",
+		BodySize:   256,
+		Body:       `{"name":"test user","email":"test@example.com","data":"some payload data here"}`,
+		StatusCode: 200,
+		LatencyMs:  42,
+	}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		// Simulate old behavior: allocate new buffer each time
+		data, _ := json.Marshal(entry)
+		_, _ = l.output.Write(append(data, '\n'))
+	}
+}
+
+// BenchmarkReadBodyLimited benchmarks reading body with sync.Pool
+func BenchmarkReadBodyLimited(b *testing.B) {
+	bodyData := bytes.Repeat([]byte("a"), 1024)
+	transport := &loggingTransport{}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		// Create a new ReadCloser for each iteration
+		body := io.NopCloser(bytes.NewReader(bodyData))
+		_, _ = transport.readBodyLimited(body, 2048)
+	}
+}
+
+// BenchmarkReadBodyLimitedSmall benchmarks with small bodies (typical API requests)
+func BenchmarkReadBodyLimitedSmall(b *testing.B) {
+	bodyData := []byte(`{"id":123,"name":"test","active":true}`)
+	transport := &loggingTransport{}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		body := io.NopCloser(bytes.NewReader(bodyData))
+		_, _ = transport.readBodyLimited(body, 1024)
+	}
+}
+
+// BenchmarkReadBodyLimitedLarge benchmarks with large bodies
+func BenchmarkReadBodyLimitedLarge(b *testing.B) {
+	bodyData := bytes.Repeat([]byte("x"), 65536) // 64KB
+	transport := &loggingTransport{}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		body := io.NopCloser(bytes.NewReader(bodyData))
+		_, _ = transport.readBodyLimited(body, 65536)
+	}
+}
+
+// BenchmarkBufferPoolGetPut benchmarks the buffer pool itself
+func BenchmarkBufferPoolGetPut(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			bufPtr := bufferPool.Get().(*[]byte)
+			// Reset and use the buffer to simulate real usage
+			*bufPtr = (*bufPtr)[:0]
+			*bufPtr = append(*bufPtr, "test data..."...)
+			bufferPool.Put(bufPtr)
+		}
+	})
+}
+
+// BenchmarkLogBufferPoolGetPut benchmarks the log buffer pool
+func BenchmarkLogBufferPoolGetPut(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			buf := logBufferPool.Get().(*bytes.Buffer)
+			buf.Reset()
+			buf.WriteString("test log entry")
+			logBufferPool.Put(buf)
+		}
+	})
+}
+
+// BenchmarkFlattenHeaders benchmarks header flattening with pooling
+func BenchmarkFlattenHeaders(b *testing.B) {
+	headers := http.Header{
+		"Content-Type": []string{"application/json"},
+		"Accept":       []string{"text/html", "application/json"},
+		"User-Agent":   []string{"test-client/1.0"},
+		"X-Request-ID": []string{"abc-123-def"},
+	}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = flattenHeaders(headers)
+	}
+}
+
+// BenchmarkTruncateBody benchmarks body truncation with pooled buffers
+func BenchmarkTruncateBody(b *testing.B) {
+	body := "this is a very long body that should be truncated for logging purposes"
+	maxLen := 20
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = truncateBody(body, maxLen)
+	}
+}
+
+// BenchmarkTruncateBodyNoPool simulates truncation without pooling
+func BenchmarkTruncateBodyNoPool(b *testing.B) {
+	body := "this is a very long body that should be truncated for logging purposes"
+	maxLen := 20
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if len(body) > maxLen {
+			_ = body[:maxLen] + "...(truncated)"
+		}
+	}
+}
+
+// BenchmarkLoggerLogWithTruncation benchmarks logging with body truncation
+func BenchmarkLoggerLogWithTruncation(b *testing.B) {
+	l := &Logger{
+		forwardID:  "benchmark",
+		maxBodyLen: 50,
+		output:     io.Discard,
+	}
+
+	entry := Entry{
+		Direction: "request",
+		RequestID: "req-123",
+		Method:    "POST",
+		Path:      "/api/users",
+		Body:      `{"name":"test user","email":"test@example.com","data":"some payload data here for truncation"}`,
+		BodySize:  100,
+	}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		_ = l.Log(entry)
+	}
+}
+
+// BenchmarkReadBufferPool benchmarks the read buffer pool
+func BenchmarkReadBufferPool(b *testing.B) {
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			bufPtr := readBufferPool.Get().(*[]byte)
+			buf := *bufPtr
+			_ = len(buf) // Use the buffer
+			readBufferPool.Put(bufPtr)
+		}
+	})
+}
+
+// BenchmarkReadBodyLimitedParallel benchmarks body reading under concurrent load
+func BenchmarkReadBodyLimitedParallel(b *testing.B) {
+	bodyData := bytes.Repeat([]byte("x"), 4096)
+	transport := &loggingTransport{}
+
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			body := io.NopCloser(bytes.NewReader(bodyData))
+			_, _ = transport.readBodyLimited(body, 8192)
+		}
+	})
+}
+
+// BenchmarkLoggerLogParallel benchmarks logging under concurrent load
+func BenchmarkLoggerLogParallel(b *testing.B) {
+	l := &Logger{
+		forwardID:  "benchmark",
+		maxBodyLen: 1024,
+		output:     io.Discard,
+	}
+
+	entry := Entry{
+		Direction: "request",
+		RequestID: "req-123",
+		Method:    "POST",
+		Path:      "/api/users",
+		Body:      `{"name":"test user"}`,
+		BodySize:  100,
+	}
+
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			_ = l.Log(entry)
+		}
+	})
+}
+
+// BenchmarkCompleteFlow benchmarks the complete logging flow
+func BenchmarkCompleteFlow(b *testing.B) {
+	l := &Logger{
+		forwardID:  "benchmark",
+		maxBodyLen: 1024,
+		output:     io.Discard,
+	}
+
+	headers := http.Header{
+		"Content-Type": []string{"application/json"},
+		"Accept":       []string{"application/json"},
+	}
+
+	bodyData := []byte(`{"id":123,"name":"test"}`)
+	transport := &loggingTransport{}
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		// Simulate full request logging flow
+		entry := Entry{
+			Direction: "request",
+			RequestID: "req-123",
+			Method:    "POST",
+			Path:      "/api/users",
+			Headers:   flattenHeaders(headers),
+			BodySize:  len(bodyData),
+			Body:      string(bodyData),
+		}
+		_ = l.Log(entry)
+
+		// Simulate body reading
+		body := io.NopCloser(bytes.NewReader(bodyData))
+		_, _ = transport.readBodyLimited(body, 2048)
+	}
+}

internal/httplog/logger.go

@@ -13,6 +13,7 @@
 package httplog
 
 import (
+	"bytes"
 	"encoding/json"
 	"io"
 	"os"
@@ -20,6 +21,14 @@ import (
 	"time"
 )
 
+// logBufferPool is used to reuse byte buffers for JSON encoding.
+// This reduces allocations when serializing log entries.
+var logBufferPool = sync.Pool{
+	New: func() interface{} {
+		return bytes.NewBuffer(make([]byte, 0, 4096))
+	},
+}
+
 // Entry represents a single HTTP log entry
 type Entry struct {
 	Timestamp  time.Time         `json:"timestamp"`
@@ -89,18 +98,50 @@ func (l *Logger) ClearCallbacks() {
 	l.callbacks = nil
 }
 
-// Log writes a log entry as JSON
+// stringBuilderPool provides reusable string builders for body truncation.
+// This reduces allocations when building truncated body strings.
+var stringBuilderPool = sync.Pool{
+	New: func() interface{} {
+		return &bytes.Buffer{}
+	},
+}
+
+// truncateBody truncates a body string to maxLen, adding a suffix if truncated.
+// Uses a pooled buffer to avoid allocations during truncation.
+func truncateBody(body string, maxLen int) string {
+	if len(body) <= maxLen {
+		return body
+	}
+
+	// Use pooled buffer for truncation
+	buf := stringBuilderPool.Get().(*bytes.Buffer)
+	buf.Reset()
+	defer stringBuilderPool.Put(buf)
+
+	// Write truncated content
+	buf.WriteString(body[:maxLen])
+	buf.WriteString("...(truncated)")
+	return buf.String()
+}
+
+// Log writes a log entry as JSON using a pooled buffer to reduce allocations.
 func (l *Logger) Log(entry Entry) error {
 	entry.ForwardID = l.forwardID
 	entry.Timestamp = time.Now()
 
-	// Truncate body if too large
+	// Truncate body if too large using pooled buffer
 	if len(entry.Body) > l.maxBodyLen {
-		entry.Body = entry.Body[:l.maxBodyLen] + "...(truncated)"
+		entry.Body = truncateBody(entry.Body, l.maxBodyLen)
 	}
 
-	data, err := json.Marshal(entry)
-	if err != nil {
+	// Get a buffer from the pool
+	buf := logBufferPool.Get().(*bytes.Buffer)
+	buf.Reset() // Clear any previous content
+	defer logBufferPool.Put(buf)
+
+	// Encode JSON directly into the pooled buffer
+	encoder := json.NewEncoder(buf)
+	if err := encoder.Encode(entry); err != nil {
 		return err
 	}
 
@@ -112,7 +153,7 @@ func (l *Logger) Log(entry Entry) error {
 		cb(entry)
 	}
 
-	_, err = l.output.Write(append(data, '\n'))
+	_, err := l.output.Write(buf.Bytes())
 	return err
 }
 

internal/httplog/proxy.go

@@ -14,10 +14,29 @@ import (
 	"sync/atomic"
 	"time"
 
-	"github.com/nvm/kportal/internal/config"
-	"github.com/nvm/kportal/internal/logger"
+	"github.com/lukaszraczylo/kportal/internal/config"
+	"github.com/lukaszraczylo/kportal/internal/logger"
 )
 
+// bufferPool is used to reuse byte buffers for body reading.
+// This significantly reduces GC pressure under high load.
+// Using *([]byte) to avoid allocations when storing/retrieving from pool (SA6002).
+var bufferPool = sync.Pool{
+	New: func() interface{} {
+		buf := make([]byte, 0, 8192) // Start with 8KB capacity
+		return &buf
+	},
+}
+
+// readBufferPool provides fixed-size buffers for io.Reader operations.
+// Using a pool eliminates per-read allocations of temporary buffers.
+var readBufferPool = sync.Pool{
+	New: func() interface{} {
+		buf := make([]byte, 4096) // 4KB fixed-size read buffer
+		return &buf
+	},
+}
+
 // Proxy is an HTTP reverse proxy with logging capabilities
 type Proxy struct {
 	listener     net.Listener
@@ -218,27 +237,73 @@ func (t *loggingTransport) RoundTrip(req *http.Request) (*http.Response, error)
 // Returns the body content (up to maxSize bytes) and the actual content length.
 // If the body exceeds maxSize, it reads only maxSize bytes for logging but
 // consumes the entire body to get the true size for BodySize reporting.
+// Uses sync.Pool to reuse buffers and reduce allocations.
 func (t *loggingTransport) readBodyLimited(body io.ReadCloser, maxSize int) ([]byte, int) {
+	// Get a buffer from the pool for accumulating body content
+	bufPtr := bufferPool.Get().(*[]byte)
+	buf := *bufPtr
+	buf = buf[:0] // Reset length but keep capacity
+	defer bufferPool.Put(bufPtr)
+
+	// Get a pooled read buffer to eliminate per-read allocation
+	tmpPtr := readBufferPool.Get().(*[]byte)
+	tmp := *tmpPtr
+	defer readBufferPool.Put(tmpPtr)
+
 	// Read up to maxSize+1 to detect if there's more
 	limitedReader := io.LimitReader(body, int64(maxSize+1))
-	data, err := io.ReadAll(limitedReader)
-	if err != nil {
-		return nil, 0
+
+	// Read into the pooled buffer
+	var totalRead int
+	for {
+		n, err := limitedReader.Read(tmp)
+		if n > 0 {
+			buf = append(buf, tmp[:n]...)
+			totalRead += n
+		}
+		if err != nil {
+			break
+		}
 	}
 
-	actualSize := len(data)
+	actualSize := len(buf)
 	wasTruncated := actualSize > maxSize
 
 	// If we read exactly maxSize+1, there might be more data
 	// Discard the rest but count the bytes for accurate BodySize
 	if wasTruncated {
-		data = data[:maxSize] // Keep only maxSize bytes for logging
 		// Count remaining bytes without storing them
 		remaining, _ := io.Copy(io.Discard, body)
 		actualSize = maxSize + int(remaining)
+		// Return a copy of just the maxSize bytes for logging
+		resultPtr := bufferPool.Get().(*[]byte)
+		result := *resultPtr
+		result = result[:maxSize]
+		copy(result, buf)
+		return result, actualSize
 	}
 
-	return data, actualSize
+	// For small results, allocate minimally. For larger results, use pooled buffer.
+	resultLen := len(buf)
+	var result []byte
+	if resultLen <= 4096 {
+		// Small body: allocate exact size to avoid holding large buffers
+		result = make([]byte, resultLen)
+		copy(result, buf)
+	} else {
+		// Larger body: try to use pooled buffer
+		resultPtr := bufferPool.Get().(*[]byte)
+		result = *resultPtr
+		if cap(result) >= resultLen {
+			result = result[:resultLen]
+			copy(result, buf)
+		} else {
+			// Pooled buffer too small, allocate new and don't return to pool
+			result = make([]byte, resultLen)
+			copy(result, buf)
+		}
+	}
+	return result, actualSize
 }
 
 // shouldLog checks if the request path matches the filter
@@ -274,7 +339,8 @@ func (p *Proxy) logError(req *http.Request, err error) {
 	_ = p.logger.Log(entry)
 }
 
-// flattenHeaders converts http.Header to map[string]string
+// flattenHeaders converts http.Header to map[string]string.
+// Pre-allocates the map with the exact size needed to avoid reallocations.
 func flattenHeaders(h http.Header) map[string]string {
 	result := make(map[string]string, len(h))
 	for k, v := range h {

internal/httplog/proxy_test.go

@@ -8,7 +8,7 @@ import (
 	"os"
 	"testing"
 
-	"github.com/nvm/kportal/internal/config"
+	"github.com/lukaszraczylo/kportal/internal/config"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 )