[#17] 통신을 위한 네트워크 관련 베이스 코드 작성

- 레트로핏 CallAdapter 적용

app/src/main/AndroidManifest.xml

@@ -2,6 +2,8 @@
 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.moyerun.moyeorun_android">
 
+    <uses-permission android:name="android.permission.INTERNET"/>
+
     <application
         android:name=".MoyeoRunApplication"
         android:allowBackup="true"

app/src/main/java/com/moyerun/moyeorun_android/MainActivity.kt

@@ -3,8 +3,7 @@ package com.moyerun.moyeorun_android
 import androidx.appcompat.app.AppCompatActivity
 import android.os.Bundle
 import com.moyerun.moyeorun_android.common.Lg
-import com.moyerun.moyeorun_android.network.ApiErrorCode
-import com.moyerun.moyeorun_android.network.callAdapter.NetworkResult
+import com.moyerun.moyeorun_android.network.calladapter.ApiResponse
 import com.moyerun.moyeorun_android.network.client.apiService
 import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.launch
@@ -21,35 +20,12 @@ class MainActivity : AppCompatActivity() {
         GlobalScope.launch {
             val response1 = apiService.getUserRepoList("choheeis")
             when (response1) {
-                is NetworkResult.Success -> {
+                is ApiResponse.Success -> {
                     Lg.d("getUserRepoList Success") }
-                is NetworkResult.Failure -> {
+                is ApiResponse.Failure -> {
                     // 비즈니스 로직 상의 에러
-                    // 이넘 클래스로 별도 관리하는 에러 코드와 비교하여 알맞은 로직 작성
-                    val errorCode = response1.code // 이건 상태코드이긴 한데, error 안에 코드 넣어서 보내주는 것 사용.
-                    if (errorCode == ApiErrorCode.NOT_EXIST_USER.code) {
-                        // 에러 대응
-                    }
                     Lg.d("getUserRepoList ApiError")
                 }
-                is NetworkResult.NetworkError -> {
-                    // 네트워크 에러와 언논 에러는 전처리되면 좋을 듯
-                    // Success랑 API Error만 뷰 모델에서 관리하도록.
-                    Lg.d("getUserRepoList NetworkError")
-                }
-                is NetworkResult.UnknownError -> { Lg.d("getUserRepoList UnknownError") }
-            }
-
-            val response2 = apiService.getAppName()
-            when (response2) {
-                is NetworkResult.Success -> { Lg.d("getAppName Success") }
-                is NetworkResult.Failure -> {
-                    // 비즈니스 로직 상의 에러
-                    // 이넘 클래스로 별도 관리하는 에러 코드와 비교하여 알맞은 로직 작성
-                    Lg.d("getAppName ApiError")
-                }
-                is NetworkResult.NetworkError -> { Lg.d("getAppName NetworkError") }
-                is NetworkResult.UnknownError -> { Lg.d("getAppName UnknownError") }
             }
         }
     }

app/src/main/java/com/moyerun/moyeorun_android/network/Response.kt

@@ -6,9 +6,4 @@ package com.moyerun.moyeorun_android.network
 data class Success<T>(
     val message: String,
     val data: T
-)
-
-data class Failure<T>(
-    val message: String,
-    val error: T
 )

app/src/main/java/com/moyerun/moyeorun_android/network/api/ApiService.kt

@@ -1,15 +1,11 @@
 package com.moyerun.moyeorun_android.network.api
 
-import com.moyerun.moyeorun_android.network.Failure
 import com.moyerun.moyeorun_android.network.Success
-import com.moyerun.moyeorun_android.network.callAdapter.NetworkResult
+import com.moyerun.moyeorun_android.network.calladapter.ApiResponse
 import retrofit2.http.GET
 import retrofit2.http.Path
 
 interface ApiService {
     @GET("users/{user}/repos")
-    suspend fun getUserRepoList(@Path("user") user: String): NetworkResult<Success<Any>, Failure<Any>>
-
-    @GET("appName")
-    suspend fun getAppName(): NetworkResult<Success<Any>, Failure<Any>>
+    suspend fun getUserRepoList(@Path("user") user: String): ApiResponse<Success<Any>>
 }

app/src/main/java/com/moyerun/moyeorun_android/network/calladapter/ApiResponse.kt

@@ -0,0 +1,10 @@
+package com.moyerun.moyeorun_android.network.calladapter
+
+/**
+ * Success : API 호출 성공 시, 데이터를 Wrapping 합니다.
+ * Failure : API 호출 실패 시, 에러를 Wrapping 합니다.
+ */
+sealed class ApiResponse<out T> {
+    data class Success<T>(val data: T) : ApiResponse<T>()
+    data class Failure(val error: Throwable) : ApiResponse<Nothing>()
+}

app/src/main/java/com/moyerun/moyeorun_android/network/calladapter/ApiResponseCall.kt

@@ -0,0 +1,77 @@
+package com.moyerun.moyeorun_android.network.calladapter
+
+import okhttp3.Request
+import okio.Timeout
+import retrofit2.*
+import java.lang.UnsupportedOperationException
+
+internal class ApiResponseCall<T : Any>(
+    private val delegate: Call<T>
+) : Call<ApiResponse<T>> {
+
+    override fun enqueue(callback: Callback<ApiResponse<T>>) {
+        delegate.enqueue(object : Callback<T> {
+
+            override fun onResponse(call: Call<T>, response: Response<T>) {
+                if (response.isSuccessful) {
+                    val body = response.body()
+
+                    if (body != null) {
+                        callback.onResponse(
+                            this@ApiResponseCall,
+                            Response.success(ApiResponse.Success(body))
+                        )
+                    } else {
+                        val invocation = call.request().tag(Invocation::class.java)
+                        val method = invocation?.method()
+                        val message = if (method != null) {
+                            "Response from " +
+                                    method.declaringClass.name +
+                                    '.' +
+                                    method.name +
+                                    " was null but response body type was declared as non-null"
+                        } else {
+                            "No tag is attached with Invocation::class.java. So, invocation can't find."
+                        }
+                        val e = KotlinNullPointerException(message)
+
+                        callback.onResponse(
+                            this@ApiResponseCall,
+                            Response.success(ApiResponse.Failure(e))
+                        )
+                    }
+                } else {
+                    callback.onResponse(
+                        this@ApiResponseCall,
+                        Response.success(ApiResponse.Failure(HttpException(response)))
+                    )
+                }
+            }
+
+            override fun onFailure(call: Call<T>, t: Throwable) {
+                callback.onResponse(
+                    this@ApiResponseCall,
+                    Response.success(ApiResponse.Failure(t))
+                )
+            }
+        })
+    }
+
+    override fun clone(): Call<ApiResponse<T>> = ApiResponseCall(delegate.clone())
+
+    override fun execute(): Response<ApiResponse<T>> {
+        throw UnsupportedOperationException("ApiResponseCall doesn't support execute")
+    }
+
+    override fun isExecuted(): Boolean = delegate.isExecuted
+
+    override fun cancel() {
+        delegate.cancel()
+    }
+
+    override fun isCanceled(): Boolean = delegate.isCanceled
+
+    override fun request(): Request = delegate.request()
+
+    override fun timeout(): Timeout = delegate.timeout()
+}

app/src/main/java/com/moyerun/moyeorun_android/network/calladapter/ApiResponseCallAdapter.kt

@@ -0,0 +1,14 @@
+package com.moyerun.moyeorun_android.network.calladapter
+
+import retrofit2.Call
+import retrofit2.CallAdapter
+import java.lang.reflect.Type
+
+class ApiResponseCallAdapter<T: Any>(
+    private val returnType: Type
+) : CallAdapter<T, Call<ApiResponse<T>>> {
+
+    override fun responseType(): Type = returnType
+
+    override fun adapt(call: Call<T>): Call<ApiResponse<T>> = ApiResponseCall(call)
+}