feat: log 404 requests with traceid (#1554)

rest/internal/response/headeronceresponsewriter.go

@@ -0,0 +1,57 @@
+package response
+
+import (
+	"bufio"
+	"errors"
+	"net"
+	"net/http"
+)
+
+// HeaderOnceResponseWriter is a http.ResponseWriter implementation
+// that only the first WriterHeader takes effect.
+type HeaderOnceResponseWriter struct {
+	w           http.ResponseWriter
+	wroteHeader bool
+}
+
+// NewHeaderOnceResponseWriter returns a HeaderOnceResponseWriter.
+func NewHeaderOnceResponseWriter(w http.ResponseWriter) http.ResponseWriter {
+	return &HeaderOnceResponseWriter{w: w}
+}
+
+// Flush flushes the response writer.
+func (w *HeaderOnceResponseWriter) Flush() {
+	if flusher, ok := w.w.(http.Flusher); ok {
+		flusher.Flush()
+	}
+}
+
+// Header returns the http header.
+func (w *HeaderOnceResponseWriter) Header() http.Header {
+	return w.w.Header()
+}
+
+// Hijack implements the http.Hijacker interface.
+// This expands the Response to fulfill http.Hijacker if the underlying http.ResponseWriter supports it.
+func (w *HeaderOnceResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	if hijacked, ok := w.w.(http.Hijacker); ok {
+		return hijacked.Hijack()
+	}
+
+	return nil, nil, errors.New("server doesn't support hijacking")
+}
+
+// Write writes bytes into w.
+func (w *HeaderOnceResponseWriter) Write(bytes []byte) (int, error) {
+	return w.w.Write(bytes)
+}
+
+// WriteHeader writes code into w, and not sealing the writer.
+func (w *HeaderOnceResponseWriter) WriteHeader(code int) {
+	if w.wroteHeader {
+		return
+	}
+
+	w.w.WriteHeader(code)
+	w.wroteHeader = true
+}

rest/internal/response/headeronceresponsewriter_test.go

@@ -0,0 +1,58 @@
+package response
+
+import (
+	"bufio"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestHeaderOnceResponseWriter_Flush(t *testing.T) {
+	req := httptest.NewRequest(http.MethodGet, "http://localhost", nil)
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		cw := NewHeaderOnceResponseWriter(w)
+		cw.Header().Set("X-Test", "test")
+		cw.WriteHeader(http.StatusServiceUnavailable)
+		cw.WriteHeader(http.StatusExpectationFailed)
+		_, err := cw.Write([]byte("content"))
+		assert.Nil(t, err)
+
+		flusher, ok := cw.(http.Flusher)
+		assert.True(t, ok)
+		flusher.Flush()
+	})
+
+	resp := httptest.NewRecorder()
+	handler.ServeHTTP(resp, req)
+	assert.Equal(t, http.StatusServiceUnavailable, resp.Code)
+	assert.Equal(t, "test", resp.Header().Get("X-Test"))
+	assert.Equal(t, "content", resp.Body.String())
+}
+
+func TestHeaderOnceResponseWriter_Hijack(t *testing.T) {
+	resp := httptest.NewRecorder()
+	writer := &HeaderOnceResponseWriter{
+		w: resp,
+	}
+	assert.NotPanics(t, func() {
+		writer.Hijack()
+	})
+
+	writer = &HeaderOnceResponseWriter{
+		w: mockedHijackable{resp},
+	}
+	assert.NotPanics(t, func() {
+		writer.Hijack()
+	})
+}
+
+type mockedHijackable struct {
+	*httptest.ResponseRecorder
+}
+
+func (m mockedHijackable) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	return nil, nil, nil
+}

rest/internal/response/withcoderesponsewriter.go

@@ -0,0 +1,47 @@
+package response
+
+import (
+	"bufio"
+	"errors"
+	"net"
+	"net/http"
+)
+
+// A WithCodeResponseWriter is a helper to delay sealing a http.ResponseWriter on writing code.
+type WithCodeResponseWriter struct {
+	Writer http.ResponseWriter
+	Code   int
+}
+
+// Flush flushes the response writer.
+func (w *WithCodeResponseWriter) Flush() {
+	if flusher, ok := w.Writer.(http.Flusher); ok {
+		flusher.Flush()
+	}
+}
+
+// Header returns the http header.
+func (w *WithCodeResponseWriter) Header() http.Header {
+	return w.Writer.Header()
+}
+
+// Hijack implements the http.Hijacker interface.
+// This expands the Response to fulfill http.Hijacker if the underlying http.ResponseWriter supports it.
+func (w *WithCodeResponseWriter) Hijack() (net.Conn, *bufio.ReadWriter, error) {
+	if hijacked, ok := w.Writer.(http.Hijacker); ok {
+		return hijacked.Hijack()
+	}
+
+	return nil, nil, errors.New("server doesn't support hijacking")
+}
+
+// Write writes bytes into w.
+func (w *WithCodeResponseWriter) Write(bytes []byte) (int, error) {
+	return w.Writer.Write(bytes)
+}
+
+// WriteHeader writes code into w, and not sealing the writer.
+func (w *WithCodeResponseWriter) WriteHeader(code int) {
+	w.Writer.WriteHeader(code)
+	w.Code = code
+}

rest/internal/response/withcoderesponsewriter_test.go

@@ -0,0 +1,50 @@
+package response
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestWithCodeResponseWriter(t *testing.T) {
+	req := httptest.NewRequest(http.MethodGet, "http://localhost", nil)
+	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		cw := &WithCodeResponseWriter{Writer: w}
+
+		cw.Header().Set("X-Test", "test")
+		cw.WriteHeader(http.StatusServiceUnavailable)
+		assert.Equal(t, cw.Code, http.StatusServiceUnavailable)
+
+		_, err := cw.Write([]byte("content"))
+		assert.Nil(t, err)
+
+		flusher, ok := http.ResponseWriter(cw).(http.Flusher)
+		assert.True(t, ok)
+		flusher.Flush()
+	})
+
+	resp := httptest.NewRecorder()
+	handler.ServeHTTP(resp, req)
+	assert.Equal(t, http.StatusServiceUnavailable, resp.Code)
+	assert.Equal(t, "test", resp.Header().Get("X-Test"))
+	assert.Equal(t, "content", resp.Body.String())
+}
+
+func TestWithCodeResponseWriter_Hijack(t *testing.T) {
+	resp := httptest.NewRecorder()
+	writer := &WithCodeResponseWriter{
+		Writer: resp,
+	}
+	assert.NotPanics(t, func() {
+		writer.Hijack()
+	})
+
+	writer = &WithCodeResponseWriter{
+		Writer: mockedHijackable{resp},
+	}
+	assert.NotPanics(t, func() {
+		writer.Hijack()
+	})
+}