fix: make connection resets retryable in OkHttp engine (#896)

Author: aajtodd

.changes/d50afb27-0e5c-46b3-9c9c-865a3c75dd21.json

@@ -0,0 +1,8 @@
+{
+    "id": "d50afb27-0e5c-46b3-9c9c-865a3c75dd21",
+    "type": "bugfix",
+    "description": "Retry connection reset errors in OkHttp engine",
+    "issues": [
+        "awslabs/aws-sdk-kotlin#905"
+    ]
+}

runtime/protocol/http-client-engines/http-client-engine-okhttp/jvm/src/aws/smithy/kotlin/runtime/http/engine/okhttp/OkHttpUtils.kt

@@ -19,6 +19,7 @@ import okhttp3.*
 import okhttp3.Authenticator
 import okhttp3.RequestBody.Companion.toRequestBody
 import okhttp3.internal.http.HttpMethod
+import java.io.EOFException
 import java.io.IOException
 import java.net.*
 import javax.net.ssl.SSLHandshakeException
@@ -191,16 +192,22 @@ internal inline fun<T> mapOkHttpExceptions(block: () -> T): T =
         throw HttpException(ex, ex.errCode(), ex.isRetryable())
     }
 
-private fun Exception.isRetryable(): Boolean = isCauseOrSuppressed<ConnectException>()
+private fun Exception.isRetryable(): Boolean = isCauseOrSuppressed<ConnectException>() || isConnectionClosedException()
 private fun Exception.errCode(): HttpErrorCode = when {
     isConnectTimeoutException() -> HttpErrorCode.CONNECT_TIMEOUT
+    isConnectionClosedException() -> HttpErrorCode.CONNECTION_CLOSED
     isCauseOrSuppressed<SocketTimeoutException>() -> HttpErrorCode.SOCKET_TIMEOUT
     isCauseOrSuppressed<SSLHandshakeException>() -> HttpErrorCode.TLS_NEGOTIATION_ERROR
     else -> HttpErrorCode.SDK_UNKNOWN
 }
 
 private fun Exception.isConnectTimeoutException(): Boolean =
     findCauseOrSuppressed<SocketTimeoutException>()?.message?.contains("connect", ignoreCase = true) == true
+
+private fun Exception.isConnectionClosedException(): Boolean =
+    message?.contains("unexpected end of stream") == true &&
+        (cause as? Exception)?.findCauseOrSuppressed<EOFException>()?.message?.contains("\\n not found: limit=0") == true
+
 private inline fun <reified T> Exception.isCauseOrSuppressed(): Boolean = findCauseOrSuppressed<T>() != null
 private inline fun <reified T> Exception.findCauseOrSuppressed(): T? {
     if (this is T) return this

runtime/protocol/http-client-engines/http-client-engine-okhttp/jvm/test/aws/smithy/kotlin/runtime/http/engine/okhttp/OkHttpExceptionTest.kt

@@ -7,6 +7,7 @@ package aws.smithy.kotlin.runtime.http.engine.okhttp
 
 import aws.smithy.kotlin.runtime.http.HttpErrorCode
 import aws.smithy.kotlin.runtime.http.HttpException
+import java.io.EOFException
 import java.io.IOException
 import java.net.ConnectException
 import java.net.SocketTimeoutException
@@ -33,6 +34,8 @@ class OkHttpExceptionTest {
             ExceptionTest(SocketTimeoutException("read timeout"), expectedError = HttpErrorCode.SOCKET_TIMEOUT),
             ExceptionTest(IOException(SSLHandshakeException("negotiate error")), expectedError = HttpErrorCode.TLS_NEGOTIATION_ERROR),
             ExceptionTest(ConnectException("test connect error"), expectedError = HttpErrorCode.SDK_UNKNOWN, true),
+            // see https://github.com/awslabs/aws-sdk-kotlin/issues/905
+            ExceptionTest(IOException("unexpected end of stream on https://test.aws.com", EOFException("\\n not found: limit=0 content=...")), expectedError = HttpErrorCode.CONNECTION_CLOSED, expectedRetryable = true),
         )
 
         for (test in tests) {