fixed middleware implementation, added middleware tracing for easier debug

internal/net/http/middleware/trace.go

@@ -0,0 +1,99 @@
+package middleware
+
+import (
+	"fmt"
+	"net/http"
+	"sync"
+	"time"
+
+	U "github.com/yusing/go-proxy/internal/utils"
+)
+
+type Trace struct {
+	Time        string         `json:"time,omitempty"`
+	Caller      string         `json:"caller,omitempty"`
+	URL         string         `json:"url,omitempty"`
+	Message     string         `json:"msg"`
+	ReqHeaders  http.Header    `json:"req_headers,omitempty"`
+	RespHeaders http.Header    `json:"resp_headers,omitempty"`
+	Additional  map[string]any `json:"additional,omitempty"`
+}
+
+type Traces []*Trace
+
+var traces = Traces{}
+var tracesMu sync.Mutex
+
+const MaxTraceNum = 1000
+
+func GetAllTrace() []*Trace {
+	return traces
+}
+
+func (tr *Trace) WithRequest(req *Request) *Trace {
+	if tr == nil {
+		return nil
+	}
+	tr.URL = req.RequestURI
+	tr.ReqHeaders = req.Header.Clone()
+	return tr
+}
+
+func (tr *Trace) WithResponse(resp *Response) *Trace {
+	if tr == nil {
+		return nil
+	}
+	tr.URL = resp.Request.RequestURI
+	tr.ReqHeaders = resp.Request.Header.Clone()
+	tr.RespHeaders = resp.Header.Clone()
+	return tr
+}
+
+func (tr *Trace) With(what string, additional any) *Trace {
+	if tr == nil {
+		return nil
+	}
+
+	if tr.Additional == nil {
+		tr.Additional = map[string]any{}
+	}
+	tr.Additional[what] = additional
+	return tr
+}
+
+func (m *Middleware) EnableTrace() {
+	m.trace = true
+	for _, child := range m.children {
+		child.parent = m
+		child.EnableTrace()
+	}
+}
+
+func (m *Middleware) AddTracef(msg string, args ...any) *Trace {
+	if !m.trace {
+		return nil
+	}
+	return addTrace(&Trace{
+		Time:    U.FormatTime(time.Now()),
+		Caller:  m.Fullname(),
+		Message: fmt.Sprintf(msg, args...),
+	})
+}
+
+func (m *Middleware) AddTraceRequest(msg string, req *Request) *Trace {
+	return m.AddTracef("%s", msg).WithRequest(req)
+}
+
+func (m *Middleware) AddTraceResponse(msg string, resp *Response) *Trace {
+	return m.AddTracef("%s", msg).WithResponse(resp)
+}
+
+func addTrace(t *Trace) *Trace {
+	tracesMu.Lock()
+	defer tracesMu.Unlock()
+	if len(traces) > MaxTraceNum {
+		traces = traces[1:]
+	}
+	traces = append(traces, t)
+	return t
+}