From eac1827b3e26fddeb5fc4b843f173b17a3134291 Mon Sep 17 00:00:00 2001
From: Ryo Takaishi <ryo.takaishi.0@gmail.com>
Date: Fri, 19 Jan 2024 11:22:14 +0900
Subject: [PATCH] feat: support regexp to transform uri

---
 README.md       |  2 ++
 alb_log.go      |  9 +++++++++
 alb_log_test.go | 17 +++++++++++++++++
 3 files changed, 28 insertions(+)

diff --git a/README.md b/README.md
index bb9c0be..07ca70e 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,8 @@ path_transforming_rules:
   - prefix: /api/v1/hoge
     suffix: /start
     transformed: /api/v1/hoge/$id/start
+  - regexp: /api/v1/hoge/[^/]+/stop
+    transformed: /api/v1/hoge/$id/stop
 ```
 
 Example `Dockerfile` :
diff --git a/alb_log.go b/alb_log.go
index 46bfa35..3398741 100644
--- a/alb_log.go
+++ b/alb_log.go
@@ -79,6 +79,7 @@ var requestPathRe = regexp.MustCompile(`(?P<method>.*) (?P<protocol>.*)://(?P<ho
 type PathTransformingRule struct {
 	Prefix      string
 	Suffix      string
+	Regexp      *regexp.Regexp
 	Transformed string
 }
 
@@ -96,6 +97,14 @@ func (r *AlbLogRecord) requestPath(rules []PathTransformingRule) (string, error)
 	}
 
 	for _, rule := range rules {
+		if rule.Regexp != nil {
+			if rule.Regexp.MatchString(uri) {
+				match = true
+				transformed = rule.Transformed
+				break
+			}
+		}
+
 		if rule.Prefix != "" && rule.Suffix != "" {
 			if strings.HasPrefix(uri, rule.Prefix) && strings.HasSuffix(uri, rule.Suffix) {
 				match = true
diff --git a/alb_log_test.go b/alb_log_test.go
index 6d3ddb8..961f08c 100644
--- a/alb_log_test.go
+++ b/alb_log_test.go
@@ -2,6 +2,7 @@ package main
 
 import (
 	"reflect"
+	"regexp"
 	"testing"
 	"time"
 )
@@ -257,6 +258,22 @@ func TestAlbLogRecord_RequestPath(t *testing.T) {
 			want:    "/foo/$id/bar",
 			wantErr: false,
 		},
+		{
+			name: "regexp",
+			args: args{
+				paths: []PathTransformingRule{
+					{
+						Regexp:      regexp.MustCompile(`^/foo/([^/]+)/bar$`),
+						Transformed: "/foo/$id/bar",
+					},
+				},
+			},
+			fields: fields{
+				Request: "POST https://example.com:443/foo/aaa/bar HTTP/1.1",
+			},
+			want:    "/foo/$id/bar",
+			wantErr: false,
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {