1package log
2
3import (
4 "bytes"
5 "encoding/json"
6 "io"
7 "log/slog"
8 "net/http"
9 "strings"
10 "time"
11)
12
13// NewHTTPClient creates an HTTP client with debug logging enabled when debug mode is on.
14func NewHTTPClient() *http.Client {
15 return &http.Client{
16 Transport: &HTTPRoundTripLogger{
17 Transport: http.DefaultTransport,
18 },
19 }
20}
21
22// HTTPRoundTripLogger is an http.RoundTripper that logs requests and responses.
23type HTTPRoundTripLogger struct {
24 Transport http.RoundTripper
25}
26
27// RoundTrip implements http.RoundTripper interface with logging.
28func (h *HTTPRoundTripLogger) RoundTrip(req *http.Request) (*http.Response, error) {
29 var err error
30 var save io.ReadCloser
31 save, req.Body, err = drainBody(req.Body)
32 if err != nil {
33 slog.Error(
34 "HTTP request failed",
35 "method", req.Method,
36 "url", req.URL,
37 "error", err,
38 )
39 return nil, err
40 }
41
42 slog.Debug(
43 "HTTP Request",
44 "method", req.Method,
45 "url", req.URL,
46 "body", bodyToString(save),
47 )
48
49 start := time.Now()
50 resp, err := h.Transport.RoundTrip(req)
51 duration := time.Since(start)
52 if err != nil {
53 slog.Error(
54 "HTTP request failed",
55 "method", req.Method,
56 "url", req.URL,
57 "duration_ms", duration.Milliseconds(),
58 "error", err,
59 )
60 return resp, err
61 }
62
63 save, resp.Body, err = drainBody(resp.Body)
64 slog.Debug(
65 "HTTP Response",
66 "status_code", resp.StatusCode,
67 "status", resp.Status,
68 "headers", formatHeaders(resp.Header),
69 "body", bodyToString(save),
70 "content_length", resp.ContentLength,
71 "duration_ms", duration.Milliseconds(),
72 "error", err,
73 )
74 return resp, err
75}
76
77func bodyToString(body io.ReadCloser) string {
78 if body == nil {
79 return ""
80 }
81 src, err := io.ReadAll(body)
82 if err != nil {
83 slog.Error("Failed to read body", "error", err)
84 return ""
85 }
86 var b bytes.Buffer
87 if json.Compact(&b, bytes.TrimSpace(src)) != nil {
88 // not json probably
89 return string(src)
90 }
91 return b.String()
92}
93
94// formatHeaders formats HTTP headers for logging, filtering out sensitive information.
95func formatHeaders(headers http.Header) map[string][]string {
96 filtered := make(map[string][]string)
97 for key, values := range headers {
98 lowerKey := strings.ToLower(key)
99 // Filter out sensitive headers
100 if strings.Contains(lowerKey, "authorization") ||
101 strings.Contains(lowerKey, "api-key") ||
102 strings.Contains(lowerKey, "token") ||
103 strings.Contains(lowerKey, "secret") {
104 filtered[key] = []string{"[REDACTED]"}
105 } else {
106 filtered[key] = values
107 }
108 }
109 return filtered
110}
111
112func drainBody(b io.ReadCloser) (r1, r2 io.ReadCloser, err error) {
113 if b == nil || b == http.NoBody {
114 return http.NoBody, http.NoBody, nil
115 }
116 var buf bytes.Buffer
117 if _, err = buf.ReadFrom(b); err != nil {
118 return nil, b, err
119 }
120 if err = b.Close(); err != nil {
121 return nil, b, err
122 }
123 return io.NopCloser(&buf), io.NopCloser(bytes.NewReader(buf.Bytes())), nil
124}