refactor: use AuthInterceptor

Author: giovannijunseokim

app/src/main/java/woowacourse/shopping/data/API.kt

@@ -11,19 +11,22 @@ import woowacourse.shopping.data.cart.service.CartService
 import woowacourse.shopping.data.product.service.ProductService
 
 object API {
-    private val client: OkHttpClient =
+    private val client: OkHttpClient by lazy {
         OkHttpClient
             .Builder()
+            .addAuthInterceptor()
             .addHttpLoggingInterceptor()
             .build()
+    }
 
-    private val retrofit =
+    private val retrofit by lazy {
         Retrofit
             .Builder()
             .baseUrl(BuildConfig.BASE_URL)
             .client(client)
             .addConverterFactory(Json.asConverterFactory("application/json".toMediaType()))
             .build()
+    }
 
     val productService: ProductService = retrofit.create(ProductService::class.java)
     val cartService: CartService = retrofit.create(CartService::class.java)
@@ -35,4 +38,6 @@ object API {
                     if (BuildConfig.DEBUG) HttpLoggingInterceptor.Level.BODY else HttpLoggingInterceptor.Level.NONE
             },
         )
+
+    private fun OkHttpClient.Builder.addAuthInterceptor() = addInterceptor(AuthInterceptor())
 }

app/src/main/java/woowacourse/shopping/data/AuthInterceptor.kt

@@ -0,0 +1,23 @@
+package woowacourse.shopping.data
+
+import okhttp3.Interceptor
+import okhttp3.Request
+import okhttp3.Response
+
+class AuthInterceptor : Interceptor {
+    override fun intercept(chain: Interceptor.Chain): Response {
+        val originalRequest = chain.request()
+        val authToken: String = AuthStorage.authToken ?: return chain.proceed(originalRequest)
+
+        val request: Request =
+            originalRequest
+                .newBuilder()
+                .addHeader(
+                    "Authorization",
+                    authToken,
+                ).build()
+
+        val response: Response = chain.proceed(request)
+        return response
+    }
+}

app/src/main/java/woowacourse/shopping/data/AuthStorage.kt

@@ -31,14 +31,20 @@ object AuthStorage {
         get() = storage.getString(KEY_PW, DEFAULT_PW)
         set(value) = storage.edit { putString(KEY_PW, value) }
 
-    val authorization by lazy {
-        val valueToEncode = "$id:$pw".toByteArray()
-        "Basic " + Base64.getEncoder().encodeToString(valueToEncode)
-    }
+    val authToken: String?
+        get() {
+            if (id == null || pw == null) {
+                return null
+            }
+
+            val valueToEncode = "$id:$pw".toByteArray()
+            return BASIC_AUTH_FORMAT.format(Base64.getEncoder().encodeToString(valueToEncode))
+        }
 
     private const val KEY_ID = "woowacourse.shopping.KEY_ID"
-    private const val DEFAULT_ID = "jerry8282"
+    private const val DEFAULT_ID = "giovannijunseokim"
     private const val KEY_PW = "woowacourse.shopping.KEY_PW"
     private const val DEFAULT_PW = "password"
     private const val FILE_NAME = "auth"
+    private const val BASIC_AUTH_FORMAT = "Basic %s"
 }

app/src/main/java/woowacourse/shopping/data/cart/service/CartService.kt

@@ -4,12 +4,10 @@ import retrofit2.Call
 import retrofit2.http.Body
 import retrofit2.http.DELETE
 import retrofit2.http.GET
-import retrofit2.http.Header
 import retrofit2.http.PATCH
 import retrofit2.http.POST
 import retrofit2.http.Path
 import retrofit2.http.Query
-import woowacourse.shopping.data.AuthStorage
 import woowacourse.shopping.data.cart.dto.CartItemRequest
 import woowacourse.shopping.data.cart.dto.CartQuantityResponse
 import woowacourse.shopping.data.cart.dto.CartResponse
@@ -20,35 +18,27 @@ interface CartService {
     fun getCart(
         @Query("page") page: Int,
         @Query("size") size: Int,
-        @Header("Authorization") header: String = AuthStorage.authorization,
     ): Call<CartResponse>
 
     @GET("/cart-items")
-    fun getAllCart(
-        @Header("Authorization") header: String = AuthStorage.authorization,
-    ): Call<CartResponse>
+    fun getAllCart(): Call<CartResponse>
 
     @POST("/cart-items")
     fun postCartItem(
         @Body request: CartRequest,
-        @Header("Authorization") header: String = AuthStorage.authorization,
     ): Call<Unit>
 
     @DELETE("/cart-items/{cartItemId}")
     fun deleteShoppingCartItem(
         @Path("cartItemId") cartItemId: Long,
-        @Header("Authorization") header: String = AuthStorage.authorization,
     ): Call<Unit>
 
     @PATCH("/cart-items/{id}")
     fun patchCartItemQuantity(
         @Path("id") id: Long,
         @Body request: CartItemRequest,
-        @Header("Authorization") header: String = AuthStorage.authorization,
     ): Call<Unit>
 
     @GET("/cart-items/counts")
-    fun getCartItemQuantity(
-        @Header("Authorization") header: String = AuthStorage.authorization,
-    ): Call<CartQuantityResponse>
+    fun getCartItemQuantity(): Call<CartQuantityResponse>
 }