Log access as json

Redact client IPs

1 files changed, 35 insertions, 1 deletions

diff --git a/main.go b/main.go
index f56cda1..83e11b0 100644
--- a/main.go
+++ b/main.go
@@ -1,13 +1,24 @@
 package main
 
 import (
+	"encoding/json"
 	"fmt"
 	"net/http"
+	"net"
+	"regexp"
 	"strings"
+	"time"
 )
 
 const log_length = 100
 
+type accessLog struct {
+	ClientAddr string `json:"clientAddr"`
+	RequestedPath string `json:"requestedPath"`
+	RequestTime time.Time `json:"requestTime"`
+	HttpMethod string `json:"httpMethod"`
+}
+
 func main() {
 	fs := http.FileServer(http.Dir("static"))
 
@@ -16,7 +27,13 @@ func main() {
 
 	// Define a handler function for the root path
 	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
-		addRotLog(&logs, &n, fmt.Sprintf("Accessed %s", r.URL.Path, x, n))
+		jsonData, _ := json.Marshal(accessLog{
+			ClientAddr: RedactIP(r.RemoteAddr),
+			RequestedPath: r.URL.Path,
+			RequestTime: time.Now().UTC(),
+			HttpMethod: r.Method,
+		})
+		addRotLog(&logs, &n, fmt.Sprintf("%s", string(jsonData)))
 		// Serve the index.html file from the static directory
 		http.StripPrefix("/", fs).ServeHTTP(w, r)
 	})
@@ -60,3 +77,20 @@ func addRotLog(logs *[log_length]string, last *int, value string) {
 		}
 	}
 }
+
+// RedactIP partially redacts an IP address by replacing the last octet with 'xxx'
+func RedactIP(input string) string {
+    ipRegex := `\b(?:\d{1,3}\.){3}\d{1,3}\b`
+    re := regexp.MustCompile(ipRegex)
+
+    return re.ReplaceAllStringFunc(input, func(match string) string {
+        if ip := net.ParseIP(match); ip != nil {
+            parts := strings.Split(match, ".")
+            if len(parts) == 4 {
+                parts[3] = "XXX"
+                return strings.Join(parts, ".")
+            }
+        }
+        return match
+    })
+}