refactor: move accesslog to logging/accesslog

internal/logging/accesslog/formatter.go

@@ -0,0 +1,157 @@
+package accesslog
+
+import (
+	"bytes"
+	"iter"
+	"net"
+	"net/http"
+	"strconv"
+
+	"github.com/rs/zerolog"
+	"github.com/yusing/go-proxy/internal/utils"
+)
+
+type (
+	CommonFormatter struct {
+		cfg *Fields
+	}
+	CombinedFormatter struct{ CommonFormatter }
+	JSONFormatter     struct{ CommonFormatter }
+)
+
+const LogTimeFormat = "02/Jan/2006:15:04:05 -0700"
+
+func scheme(req *http.Request) string {
+	if req.TLS != nil {
+		return "https"
+	}
+	return "http"
+}
+
+func appendRequestURI(line []byte, req *http.Request, query iter.Seq2[string, []string]) []byte {
+	uri := req.URL.EscapedPath()
+	line = append(line, uri...)
+	isFirst := true
+	for k, v := range query {
+		if isFirst {
+			line = append(line, '?')
+			isFirst = false
+		} else {
+			line = append(line, '&')
+		}
+		line = append(line, k...)
+		line = append(line, '=')
+		for _, v := range v {
+			line = append(line, v...)
+		}
+	}
+	return line
+}
+
+func clientIP(req *http.Request) string {
+	clientIP, _, err := net.SplitHostPort(req.RemoteAddr)
+	if err == nil {
+		return clientIP
+	}
+	return req.RemoteAddr
+}
+
+func (f *CommonFormatter) AppendLog(line []byte, req *http.Request, res *http.Response) []byte {
+	query := f.cfg.Query.IterQuery(req.URL.Query())
+
+	line = append(line, req.Host...)
+	line = append(line, ' ')
+
+	line = append(line, clientIP(req)...)
+	line = append(line, " - - ["...)
+
+	line = utils.TimeNow().AppendFormat(line, LogTimeFormat)
+	line = append(line, `] "`...)
+
+	line = append(line, req.Method...)
+	line = append(line, ' ')
+	line = appendRequestURI(line, req, query)
+	line = append(line, ' ')
+	line = append(line, req.Proto...)
+	line = append(line, '"')
+	line = append(line, ' ')
+
+	line = strconv.AppendInt(line, int64(res.StatusCode), 10)
+	line = append(line, ' ')
+	line = strconv.AppendInt(line, res.ContentLength, 10)
+	return line
+}
+
+func (f *CombinedFormatter) AppendLog(line []byte, req *http.Request, res *http.Response) []byte {
+	line = f.CommonFormatter.AppendLog(line, req, res)
+	line = append(line, " \""...)
+	line = append(line, req.Referer()...)
+	line = append(line, "\" \""...)
+	line = append(line, req.UserAgent()...)
+	line = append(line, '"')
+	return line
+}
+
+type zeroLogStringStringMapMarshaler struct {
+	values map[string]string
+}
+
+func (z *zeroLogStringStringMapMarshaler) MarshalZerologObject(e *zerolog.Event) {
+	if len(z.values) == 0 {
+		return
+	}
+	for k, v := range z.values {
+		e.Str(k, v)
+	}
+}
+
+type zeroLogStringStringSliceMapMarshaler struct {
+	values map[string][]string
+}
+
+func (z *zeroLogStringStringSliceMapMarshaler) MarshalZerologObject(e *zerolog.Event) {
+	if len(z.values) == 0 {
+		return
+	}
+	for k, v := range z.values {
+		e.Strs(k, v)
+	}
+}
+
+func (f *JSONFormatter) AppendLog(line []byte, req *http.Request, res *http.Response) []byte {
+	query := f.cfg.Query.ZerologQuery(req.URL.Query())
+	headers := f.cfg.Headers.ZerologHeaders(req.Header)
+	cookies := f.cfg.Cookies.ZerologCookies(req.Cookies())
+	contentType := res.Header.Get("Content-Type")
+
+	writer := bytes.NewBuffer(line)
+	logger := zerolog.New(writer).With().Logger()
+	event := logger.Info().
+		Str("time", utils.TimeNow().Format(LogTimeFormat)).
+		Str("ip", clientIP(req)).
+		Str("method", req.Method).
+		Str("scheme", scheme(req)).
+		Str("host", req.Host).
+		Str("path", req.URL.Path).
+		Str("protocol", req.Proto).
+		Int("status", res.StatusCode).
+		Str("type", contentType).
+		Int64("size", res.ContentLength).
+		Str("referer", req.Referer()).
+		Str("useragent", req.UserAgent()).
+		Object("query", query).
+		Object("headers", headers).
+		Object("cookies", cookies)
+
+	if res.StatusCode >= 400 {
+		if res.Status != "" {
+			event.Str("error", res.Status)
+		} else {
+			event.Str("error", http.StatusText(res.StatusCode))
+		}
+	}
+
+	// NOTE: zerolog will append a newline to the buffer
+	event.Send()
+	return writer.Bytes()
+}