Add response headers to Nylas API error objects (#246)

# Description
This PR forwards response headers from the Nylas API error response to
the serialized objects.

# License
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license and that I have the authority necessary to make this
contribution on behalf of its copyright owner.

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### Added
 * Added new error class `NylasSdkRemoteClosedError` for when the remote connection is closed
 * Added support for new filter fields for listing events
+* Added response headers to Nylas API error objects
 
 ### [2.4.1] - Released 2024-07-26
 

src/main/kotlin/com/nylas/NylasClient.kt

@@ -402,6 +402,7 @@ class NylasClient(
               errorUri = "unknown",
               errorCode = "0",
               statusCode = response.code(),
+              headers = response.headers().toMultimap(),
             )
           }
 
@@ -423,6 +424,7 @@ class NylasClient(
               type = "unknown",
               message = "Unknown error received from the API: $responseBody",
               statusCode = response.code(),
+              headers = response.headers().toMultimap(),
             )
           }
           else -> throw ex
@@ -432,13 +434,15 @@ class NylasClient(
 
     if (parsedError != null) {
       parsedError.statusCode = response.code()
+      parsedError.headers = response.headers().toMultimap()
       throw parsedError
     }
 
     throw NylasApiError(
       type = "unknown",
       message = "Unknown error received from the API: $responseBody",
       statusCode = response.code(),
+      headers = response.headers().toMultimap(),
     )
   }
 

src/main/kotlin/com/nylas/models/AbstractNylasApiError.kt

@@ -5,9 +5,11 @@ package com.nylas.models
  * @param message The error message.
  * @param statusCode The HTTP status code of the error response.
  * @param requestId The unique identifier of the request.
+ * @param headers The HTTP headers of the error response.
  */
 sealed class AbstractNylasApiError(
   override val message: String,
   open var statusCode: Int? = null,
   open var requestId: String? = null,
+  open var headers: Map<String, List<String>>? = null,
 ) : Exception(message)

src/main/kotlin/com/nylas/models/NylasApiError.kt

@@ -25,5 +25,12 @@ data class NylasApiError(
    * The HTTP status code of the error response
    */
   override var statusCode: Int? = null,
+  /**
+   * The HTTP status code of the error response.
+   */
   override var requestId: String? = null,
-) : AbstractNylasApiError(message, statusCode, requestId)
+  /**
+   * The HTTP headers of the error response
+   */
+  override var headers: Map<String, List<String>>? = null,
+) : AbstractNylasApiError(message, statusCode, requestId, headers)

src/main/kotlin/com/nylas/models/NylasOAuthError.kt

@@ -35,4 +35,8 @@ data class NylasOAuthError(
    * The HTTP status code of the error response.
    */
   override var statusCode: Int? = null,
-) : AbstractNylasApiError(error, statusCode, requestId)
+  /**
+   * The HTTP headers of the error response
+   */
+  override var headers: Map<String, List<String>>? = null,
+) : AbstractNylasApiError(error, statusCode, requestId, headers)

src/test/kotlin/com/nylas/NylasClientTest.kt

@@ -182,6 +182,8 @@ class NylasClientTest {
     private val mockCall: Call = mock(Call::class.java)
     private val mockResponse: Response = mock(Response::class.java)
     private val mockResponseBody: ResponseBody = mock(ResponseBody::class.java)
+    private val mockHeaderResponse: Headers = mock(Headers::class.java)
+    private val headersMultiMap = mapOf("header1" to listOf("value1"), "header2" to listOf("value2"))
 
     @Captor
     private lateinit var requestCaptor: ArgumentCaptor<Request>
@@ -196,6 +198,8 @@ class NylasClientTest {
       whenever(mockCall.execute()).thenReturn(mockResponse)
       whenever(mockResponse.isSuccessful).thenReturn(true)
       whenever(mockResponse.body()).thenReturn(mockResponseBody)
+      whenever(mockResponse.headers()).thenReturn(mockHeaderResponse)
+      whenever(mockHeaderResponse.toMultimap()).thenReturn(headersMultiMap)
       nylasClient = NylasClient("testApiKey", mockOkHttpClientBuilder)
     }
 
@@ -232,6 +236,8 @@ class NylasClientTest {
         assertEquals("https://accounts.nylas.io/#tag/Event-Codes", exception.errorUri)
         assertEquals("500", exception.errorCode)
         assertEquals(401, exception.statusCode)
+        assertEquals("eccc9c3f-7150-48e1-965e-4f89714ab51a", exception.requestId)
+        assertEquals(headersMultiMap, exception.headers)
       }
     }
 
@@ -254,6 +260,7 @@ class NylasClientTest {
         assertEquals("unknown", exception.errorUri)
         assertEquals("0", exception.errorCode)
         assertEquals(500, exception.statusCode)
+        assertEquals(headersMultiMap, exception.headers)
       }
     }
 
@@ -273,6 +280,7 @@ class NylasClientTest {
       assertEquals("Request had invalid authentication credentials.", exception.providerError?.get("error"))
       assertEquals("4c2740b4-52a4-412e-bdee-49a6c6671b22", exception.requestId)
       assertEquals(400, exception.statusCode)
+      assertEquals(headersMultiMap, exception.headers)
     }
 
     @Test
@@ -289,6 +297,7 @@ class NylasClientTest {
       assertEquals("unknown", exception.type)
       assertEquals("Unknown error received from the API: not a json", exception.message)
       assertEquals(400, exception.statusCode)
+      assertEquals(headersMultiMap, exception.headers)
     }
 
     @Test