refactor: UrlConverter 에게 url 변환 로직 위임

src/main/kotlin/com/petqua/application/image/ImageStorageService.kt

@@ -9,12 +9,10 @@ import org.springframework.web.multipart.MultipartFile
 @Service
 class ImageStorageService(
     private val amazonS3: AmazonS3,
+    private val urlConverter: UrlConverter,
 
     @Value("\${cloud.aws.s3.bucket}")
     private val bucket: String,
-
-    @Value("\${image.common.domain}")
-    private val domain: String,
 ) {
 
     fun upload(path: String, image: MultipartFile): String {
@@ -25,7 +23,6 @@ class ImageStorageService(
         amazonS3.putObject(bucket, path, image.inputStream, metadata)
 
         val storedUrl = amazonS3.getUrl(bucket, path).toString()
-        val pathIndex = storedUrl.indexOf("/$path")
-        return "$domain${storedUrl.substring(pathIndex)}" // cloudfront 로 우회해 이미지에 접근할 수 있는 URL
+        return urlConverter.convertToAccessibleUrl(path, storedUrl)
     }
 }

src/main/kotlin/com/petqua/application/image/UrlConverter.kt

@@ -0,0 +1,26 @@
+package com.petqua.application.image
+
+import org.springframework.beans.factory.annotation.Value
+import org.springframework.stereotype.Component
+
+@Component
+class UrlConverter(
+    @Value("\${image.common.domain}")
+    private val domain: String,
+) {
+
+    fun convertToAccessibleUrl(filePath: String, storedUrl: String): String {
+        /*
+        * example)
+        * filePath = "root/directory/image.jpeg"
+        * storedUrl = "https://storedUrl.com/root/directory/image.jpeg"
+        *
+        * pathIndex = 21
+        * storedPath = "/root/directory/image.jpeg"
+        * return "https://domain.com/root/directory/image.jpeg"
+        * */
+        val pathIndex = storedUrl.indexOf("/$filePath")
+        val storedPath = storedUrl.substring(pathIndex)
+        return "$domain$storedPath"
+    }
+}

src/test/kotlin/com/petqua/application/image/UrlConverterTest.kt

@@ -0,0 +1,18 @@
+package com.petqua.application.image
+
+import io.kotest.core.spec.style.StringSpec
+import io.kotest.matchers.shouldBe
+
+class UrlConverterTest : StringSpec({
+
+    "파일 경로와 파일이 저장된 url 을 입력해 접근 가능한 url로 변환한다" {
+        val domainUrl = "https://domain.com"
+        val filePath = "root/directory/image.jpeg"
+        val storedUrl = "https://storedUrl.com/root/directory/image.jpeg"
+        val urlConverter = UrlConverter(domainUrl)
+
+        val accessibleUrl = urlConverter.convertToAccessibleUrl(filePath, storedUrl)
+
+        accessibleUrl shouldBe "https://domain.com/root/directory/image.jpeg"
+    }
+})