Merge pull request #31 from gilgoldzweig/master

Added [NetworkResponse.Error] an interface to generalize errors

Author: haroldadmin

README.md

@@ -82,6 +82,16 @@ It is generic on two types: a response (`S`), and an error (`E`). The response t
       // or if you use suspending functions,
       val person = apiService.getPerson()
 
+      when (person) {
+          is NetworkResponse.Success -> {
+              // Handle successful response
+          }
+          is NetworkResponse.Error -> {
+              // Handle error
+          }
+      }
+  
+      // If you care about what type of error
       when (person) {
           is NetworkResponse.Success -> {
               // Handle successful response

src/main/kotlin/com/haroldadmin/cnradapter/NetworkResponse.kt

@@ -13,28 +13,51 @@ sealed class NetworkResponse<out T : Any, out U : Any> {
         val code: Int
     ) : NetworkResponse<T, Nothing>()
 
+    fun wasSuccessful(): Boolean = this is Success
+
+    /**
+     * Describe an error without a specific type.
+     * Makes it easier to deal with the case where you just want to know that an error occurred,
+     * without knowing the type
+     *
+     * @example
+     * val response = someNetworkAction()
+     *
+     * when (response) {
+     *    is NetworkResponse.Success -> // Action Succeeded do something with body
+     *
+     *    is NetworkResponse.Error -> // Action failed do something with error
+     * }
+     */
+    interface Error {
+        val error: Throwable
+    }
+
     /**
      * A request that resulted in a response with a non-2xx status code.
      */
     data class ServerError<U : Any>(
         val body: U?,
         val code: Int,
         val headers: Headers? = null
-    ) : NetworkResponse<Nothing, U>()
+    ) : NetworkResponse<Nothing, U>(), Error {
+        override val error = IOException("Network server error: $code \n$body")
+    }
 
     /**
      * A request that didn't result in a response.
      */
-    data class NetworkError(val error: IOException) : NetworkResponse<Nothing, Nothing>()
+    data class NetworkError(override val error: IOException) :
+        NetworkResponse<Nothing, Nothing>(), Error
 
     /**
      * A request that resulted in an error different from an IO or Server error.
      *
      * An example of such an error is JSON parsing exception thrown by a serialization library.
      */
     data class UnknownError(
-        val error: Throwable,
+        override val error: Throwable,
         val code: Int? = null,
         val headers: Headers? = null,
-    ) : NetworkResponse<Nothing, Nothing>()
+    ) : NetworkResponse<Nothing, Nothing>(), Error
 }

src/test/kotlin/com/haroldadmin/cnradapter/ErrorExtractionTest.kt

@@ -22,10 +22,10 @@ internal class ErrorExtractionTest: AnnotationSpec() {
         val serverResponse = "Server Error".toResponseBody()
         val response = Response.error<String>(404, serverResponse)
         val exception = HttpException(response)
-        with(exception.extractFromHttpException<String>(errorConverter)) {
+        with(exception.extractFromHttpException(errorConverter)) {
 
             shouldBeTypeOf<NetworkResponse.ServerError<String>>()
-            this as NetworkResponse.ServerError
+
 
             body shouldBe errorConverter.convert(serverResponse)
             code shouldBe 404
@@ -54,7 +54,7 @@ internal class ErrorExtractionTest: AnnotationSpec() {
         with(response) {
             shouldBeTypeOf<NetworkResponse.UnknownError>()
             this as NetworkResponse.UnknownError
-            this.error shouldBe exception
+            error shouldBe exception
         }
     }
 }