feat : SOLID - DIP 샘플 코드 구현

놀이터(예제 코드 작성)/solid-design-pattern-sample/README.md

@@ -47,6 +47,19 @@
 - 영화 상영관 좌석 현황을 조회할 수 있다.
 - 영화표 예매를 진행할 수 있다.
 
+### DIP(Dependency Inversion Principle)
+
+- 의존 역전 원칙
+- 프로그래머는 “추상화에 의존해야지, 구체화에 의존하면 안된다.” 의존성 주입은 이 원칙을 따르는 방법 중 하나다.
+
+#### 구현 요구사항
+
+- 저장소에서 파일 데이터를 불러올 수 있다.
+- 하나의 저장소만 사용하며 저장소의 타입은 언제든지 변경될 수 있다.
+- 각각의 저장소는 각자만의 파일 데이터 조회 요청 인터페이스를 제공한다.
+  - 아마존에서는 파일 이름을 요구한다.
+  - 구글에서는 파일 번호를 요구한다.
+
 ## 참고자료
 
 - [SOLID (객체 지향 설계)](https://ko.wikipedia.org/wiki/SOLID_(%EA%B0%9D%EC%B2%B4_%EC%A7%80%ED%96%A5_%EC%84%A4%EA%B3%84)) 

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/after/AmazonStorageService.kt

@@ -0,0 +1,19 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.after
+
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.AmazonStorage
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.AmazonStorageReadFileRequest
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.ReadFileRequest
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.StorageFile
+import org.springframework.stereotype.Service
+
+@Service
+class AmazonStorageService : StorageService {
+    override fun readStorageFile(request: ReadFileRequest): StorageFile {
+        val storage = AmazonStorage()
+        val amazonStorageReadFileRequest = object : AmazonStorageReadFileRequest {
+            override val fileName: String
+                get() = request.fileInformation
+        }
+        return storage.provideStorageFile(amazonStorageReadFileRequest)
+    }
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/after/GoogleStorageService.kt

@@ -0,0 +1,19 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.after
+
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.GoogleStorage
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.GoogleStorageReadFileRequest
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.ReadFileRequest
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.StorageFile
+import org.springframework.stereotype.Component
+
+@Component
+class GoogleStorageService : StorageService {
+    override fun readStorageFile(request: ReadFileRequest): StorageFile {
+        val storage = GoogleStorage()
+        val googleStorageReadFileRequest = object : GoogleStorageReadFileRequest {
+            override val fileNumber: Int
+                get() = request.fileInformation.toInt()
+        }
+        return storage.provideStorageFile(googleStorageReadFileRequest)
+    }
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/after/StorageControllerAfter.kt

@@ -0,0 +1,18 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.after
+
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.ReadFileRequest
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.StorageFile
+import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.RequestMapping
+import org.springframework.web.bind.annotation.RestController
+
+@RequestMapping("/storages")
+@RestController
+class StorageControllerAfter(
+    private val storageService: StorageService
+) {
+    @GetMapping("/with-dip")
+    fun readStorageFile(request: ReadFileRequest): StorageFile {
+        return storageService.readStorageFile(request)
+    }
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/after/StorageService.kt

@@ -0,0 +1,8 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.after
+
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.ReadFileRequest
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.StorageFile
+
+interface StorageService {
+    fun readStorageFile(request: ReadFileRequest): StorageFile
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/after/StorageServiceConfiguration.kt

@@ -0,0 +1,24 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.after
+
+import org.springframework.context.annotation.Bean
+import org.springframework.context.annotation.Configuration
+
+@Configuration
+class StorageServiceConfiguration {
+
+    /**
+     * AmazonStorageService 를 적용하고 싶은 경우
+     */
+    @Bean
+    fun storageService(): StorageService {
+        return AmazonStorageService()
+    }
+
+    /**
+     * GoogleStorageService 를 적용하고 싶은 경우
+     */
+//    @Bean
+//    fun storageService(): StorageService {
+//        return GoogleStorageService()
+//    }
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/before/StorageControllerBefore.kt

@@ -0,0 +1,26 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.before
+
+import com.banjjoknim.soliddesignpatternsample.solid.dip.after.AmazonStorageService
+import com.banjjoknim.soliddesignpatternsample.solid.dip.after.GoogleStorageService
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.ReadFileRequest
+import com.banjjoknim.soliddesignpatternsample.solid.dip.common.StorageFile
+import org.springframework.web.bind.annotation.GetMapping
+import org.springframework.web.bind.annotation.RequestMapping
+import org.springframework.web.bind.annotation.RequestParam
+import org.springframework.web.bind.annotation.RestController
+
+@RequestMapping("/storages")
+@RestController
+class StorageControllerBefore(
+    private val amazonStorageService: AmazonStorageService,
+    private val googleStorageService: GoogleStorageService,
+) {
+    @GetMapping("/none-dip")
+    fun readStorageFile(@RequestParam storageType: StorageType, @RequestParam fileInformation: String): StorageFile {
+        val readFileRequest = ReadFileRequest(fileInformation)
+        return when (storageType) {
+            StorageType.AMAZON -> amazonStorageService.readStorageFile(readFileRequest)
+            StorageType.GOOGLE -> googleStorageService.readStorageFile(readFileRequest)
+        }
+    }
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/before/StorageType.kt

@@ -0,0 +1,6 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.before
+
+enum class StorageType {
+    AMAZON,
+    GOOGLE
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/common/AmazonStorage.kt

@@ -0,0 +1,7 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.common
+
+class AmazonStorage {
+    fun provideStorageFile(request: AmazonStorageReadFileRequest): StorageFile {
+        return StorageFile("${request.fileName} data from amazon")
+    }
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/common/AmazonStorageReadFileRequest.kt

@@ -0,0 +1,5 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.common
+
+interface AmazonStorageReadFileRequest {
+    val fileName: String
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/common/GoogleStorage.kt

@@ -0,0 +1,7 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.common
+
+class GoogleStorage {
+    fun provideStorageFile(request: GoogleStorageReadFileRequest): StorageFile {
+        return StorageFile("${request.fileNumber} data from amazon")
+    }
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/common/GoogleStorageReadFileRequest.kt

@@ -0,0 +1,5 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.common
+
+interface GoogleStorageReadFileRequest {
+    val fileNumber: Int
+}

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/common/ReadFileRequest.kt

@@ -0,0 +1,5 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.common
+
+data class ReadFileRequest(
+    val fileInformation: String
+)

놀이터(예제 코드 작성)/solid-design-pattern-sample/src/main/kotlin/com/banjjoknim/soliddesignpatternsample/solid/dip/common/StorageFile.kt

@@ -0,0 +1,5 @@
+package com.banjjoknim.soliddesignpatternsample.solid.dip.common
+
+data class StorageFile(
+    val data: String
+)