Introduce EventListener.requestFailed, responseFailed events

These replace requestBodyEnd() / responseBodyEnd() in some failure scenarios.
They may also be issued in cases where no event was published previously.

okhttp-logging-interceptor/src/main/java/okhttp3/logging/LoggingEventListener.java

@@ -124,6 +124,11 @@ public final class LoggingEventListener extends EventListener {
     logWithTime("requestBodyEnd: byteCount=" + byteCount);
   }
 
+  @Override
+  public void requestFailed(Call call, IOException ioe) {
+    logWithTime("requestFailed: " + ioe);
+  }
+
   @Override
   public void responseHeadersStart(Call call) {
     logWithTime("responseHeadersStart");
@@ -144,6 +149,11 @@ public final class LoggingEventListener extends EventListener {
     logWithTime("responseBodyEnd: byteCount=" + byteCount);
   }
 
+  @Override
+  public void responseFailed(Call call, IOException ioe) {
+    logWithTime("responseFailed: " + ioe);
+  }
+
   @Override
   public void callEnd(Call call) {
     logWithTime("callEnd");

okhttp-tests/src/test/java/okhttp3/CallTest.java

@@ -56,6 +56,10 @@ import javax.net.ssl.SSLPeerUnverifiedException;
 import javax.net.ssl.SSLProtocolException;
 import javax.net.ssl.SSLSocket;
 import javax.net.ssl.SSLSocketFactory;
+import okhttp3.RecordingEventListener.CallEnd;
+import okhttp3.RecordingEventListener.ConnectionAcquired;
+import okhttp3.RecordingEventListener.ConnectionReleased;
+import okhttp3.RecordingEventListener.ResponseFailed;
 import okhttp3.internal.DoubleInetAddressDns;
 import okhttp3.internal.RecordingOkAuthenticator;
 import okhttp3.internal.Util;
@@ -104,8 +108,11 @@ public final class CallTest {
   @Rule public final MockWebServer server2 = new MockWebServer();
   @Rule public final InMemoryFileSystem fileSystem = new InMemoryFileSystem();
 
+  private final RecordingEventListener listener = new RecordingEventListener();
   private HandshakeCertificates handshakeCertificates = localhost();
-  private OkHttpClient client = defaultClient();
+  private OkHttpClient client = defaultClient().newBuilder()
+      .eventListener(listener)
+      .build();
   private RecordingCallback callback = new RecordingCallback();
   private TestLogHandler logHandler = new TestLogHandler();
   private Cache cache = new Cache(new File("/cache/"), Integer.MAX_VALUE, fileSystem);
@@ -1041,6 +1048,17 @@ public final class CallTest {
 
     executeSynchronously("/").assertBody("seed connection pool");
     executeSynchronously("/").assertBody("retry success");
+
+    // The call that seeds the connection pool.
+    listener.removeUpToEvent(CallEnd.class);
+
+    // The ResponseFailed event is not necessarily fatal!
+    listener.removeUpToEvent(ConnectionAcquired.class);
+    listener.removeUpToEvent(ResponseFailed.class);
+    listener.removeUpToEvent(ConnectionReleased.class);
+    listener.removeUpToEvent(ConnectionAcquired.class);
+    listener.removeUpToEvent(ConnectionReleased.class);
+    listener.removeUpToEvent(CallEnd.class);
   }
 
   @Test public void recoverWhenRetryOnConnectionFailureIsTrue_HTTP2() throws Exception {

okhttp-tests/src/test/java/okhttp3/DuplexTest.java

@@ -319,7 +319,7 @@ public final class DuplexTest {
         "RequestHeadersStart", "RequestHeadersEnd", "RequestBodyStart", "ResponseHeadersStart",
         "ResponseHeadersEnd", "ResponseBodyStart", "ResponseBodyEnd", "RequestHeadersStart",
         "RequestHeadersEnd", "ResponseHeadersStart", "ResponseHeadersEnd", "ResponseBodyStart",
-        "ResponseBodyEnd", "ConnectionReleased", "CallEnd", "RequestBodyEnd");
+        "ResponseBodyEnd", "ConnectionReleased", "CallEnd", "RequestFailed");
     assertEquals(expectedEvents, listener.recordedEventTypes());
   }
 

okhttp-tests/src/test/java/okhttp3/EventListenerTest.java

@@ -38,6 +38,7 @@ import okhttp3.RecordingEventListener.DnsStart;
 import okhttp3.RecordingEventListener.RequestBodyEnd;
 import okhttp3.RecordingEventListener.RequestHeadersEnd;
 import okhttp3.RecordingEventListener.ResponseBodyEnd;
+import okhttp3.RecordingEventListener.ResponseFailed;
 import okhttp3.RecordingEventListener.ResponseHeadersEnd;
 import okhttp3.RecordingEventListener.SecureConnectEnd;
 import okhttp3.RecordingEventListener.SecureConnectStart;
@@ -168,7 +169,8 @@ public final class EventListenerTest {
 
     List<String> expectedEvents = Arrays.asList("CallStart", "DnsStart", "DnsEnd",
         "ConnectStart", "ConnectEnd", "ConnectionAcquired", "RequestHeadersStart",
-        "RequestHeadersEnd", "ResponseHeadersStart", "ConnectionReleased", "CallFailed");
+        "RequestHeadersEnd", "ResponseHeadersStart", "ResponseFailed", "ConnectionReleased",
+        "CallFailed");
     assertEquals(expectedEvents, listener.recordedEventTypes());
   }
 
@@ -197,10 +199,10 @@ public final class EventListenerTest {
     List<String> expectedEvents = Arrays.asList("CallStart", "DnsStart", "DnsEnd",
         "ConnectStart", "ConnectEnd", "ConnectionAcquired", "RequestHeadersStart",
         "RequestHeadersEnd", "ResponseHeadersStart", "ResponseHeadersEnd", "ResponseBodyStart",
-        "ResponseBodyEnd", "ConnectionReleased", "CallFailed");
+        "ResponseFailed", "ConnectionReleased", "CallFailed");
     assertEquals(expectedEvents, listener.recordedEventTypes());
-    ResponseBodyEnd bodyEnd = listener.removeUpToEvent(ResponseBodyEnd.class);
+    ResponseFailed responseFailed = listener.removeUpToEvent(ResponseFailed.class);
-    assertEquals(5, bodyEnd.bytesRead);
+    assertEquals("unexpected end of stream", responseFailed.ioe.getMessage());
   }
 
   @Test public void canceledCallEventSequence() {
@@ -1052,7 +1054,7 @@ public final class EventListenerTest {
 
     List<String> expectedEvents = Arrays.asList("CallStart", "DnsStart", "DnsEnd", "ConnectStart",
         "ConnectEnd", "ConnectionAcquired", "RequestHeadersStart", "RequestHeadersEnd",
-        "RequestBodyStart", "RequestBodyEnd", "ConnectionReleased", "CallFailed");
+        "RequestBodyStart", "RequestFailed", "ConnectionReleased", "CallFailed");
     assertEquals(expectedEvents, listener.recordedEventTypes());
   }
 

okhttp-tests/src/test/java/okhttp3/RecordingEventListener.java

@@ -19,18 +19,18 @@ import java.io.IOException;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.Proxy;
-import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Deque;
 import java.util.List;
+import java.util.concurrent.ConcurrentLinkedDeque;
 import javax.annotation.Nullable;
 
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
 public final class RecordingEventListener extends EventListener {
-  final Deque<CallEvent> eventSequence = new ArrayDeque<>();
+  final Deque<CallEvent> eventSequence = new ConcurrentLinkedDeque<>();
 
   final List<Object> forbiddenLocks = new ArrayList<>();
 
@@ -138,6 +138,10 @@ public final class RecordingEventListener extends EventListener {
     logEvent(new RequestBodyEnd(call, byteCount));
   }
 
+  @Override public void requestFailed(Call call, IOException ioe) {
+    logEvent(new RequestFailed(call, ioe));
+  }
+
   @Override public void responseHeadersStart(Call call) {
     logEvent(new ResponseHeadersStart(call));
   }
@@ -154,6 +158,10 @@ public final class RecordingEventListener extends EventListener {
     logEvent(new ResponseBodyEnd(call, byteCount));
   }
 
+  @Override public void responseFailed(Call call, IOException ioe) {
+    logEvent(new ResponseFailed(call, ioe));
+  }
+
   @Override public void callEnd(Call call) {
     logEvent(new CallEnd(call));
   }
@@ -374,6 +382,15 @@ public final class RecordingEventListener extends EventListener {
     }
   }
 
+  static final class RequestFailed extends CallEvent {
+    final IOException ioe;
+
+    RequestFailed(Call call, IOException ioe) {
+      super(call, ioe);
+      this.ioe = ioe;
+    }
+  }
+
   static final class ResponseHeadersStart extends CallEvent {
     ResponseHeadersStart(Call call) {
       super(call);
@@ -411,4 +428,13 @@ public final class RecordingEventListener extends EventListener {
       return new ResponseBodyStart(call);
     }
   }
+
+  static final class ResponseFailed extends CallEvent {
+    final IOException ioe;
+
+    ResponseFailed(Call call, IOException ioe) {
+      super(call, ioe);
+      this.ioe = ioe;
+    }
+  }
 }

okhttp/src/main/java/okhttp3/EventListener.java

@@ -46,7 +46,7 @@ import javax.annotation.Nullable;
  * events.
  *
  * <p>All event methods must execute fast, without external locking, cannot throw exceptions,
- * attempt to mutate the event parameters, or be reentrant back into the client.
+ * attempt to mutate the event parameters, or be re-entrant back into the client.
  * Any IO - writing to files or network should be done asynchronously.
  */
 public abstract class EventListener {
@@ -210,6 +210,15 @@ public abstract class EventListener {
   public void requestBodyEnd(Call call, long byteCount) {
   }
 
+  /**
+   * Invoked when a request fails to be written.
+   *
+   * <p>This method is invoked after {@link #requestHeadersStart} or {@link #requestBodyStart}. Note
+   * that request failures do not necessarily fail the entire call.
+   */
+  public void requestFailed(Call call, IOException ioe) {
+  }
+
   /**
    * Invoked just prior to receiving response headers.
    *
@@ -256,6 +265,15 @@ public abstract class EventListener {
   public void responseBodyEnd(Call call, long byteCount) {
   }
 
+  /**
+   * Invoked when a response fails to be read.
+   *
+   * <p>This method is invoked after {@link #responseHeadersStart} or {@link #responseBodyStart}.
+   * Note that response failures do not necessarily fail the entire call.
+   */
+  public void responseFailed(Call call, IOException ioe) {
+  }
+
   /**
    * Invoked immediately after a call has completely ended.  This includes delayed consumption
    * of response body by the caller.

okhttp/src/main/java/okhttp3/internal/connection/Exchange.java

@@ -66,6 +66,7 @@ public final class Exchange {
       codec.writeRequestHeaders(request);
       eventListener.requestHeadersEnd(call, request);
     } catch (IOException e) {
+      eventListener.requestFailed(call, e);
       trackFailure(e);
       throw e;
     }
@@ -82,6 +83,7 @@ public final class Exchange {
     try {
       codec.flushRequest();
     } catch (IOException e) {
+      eventListener.requestFailed(call, e);
       trackFailure(e);
       throw e;
     }
@@ -91,6 +93,7 @@ public final class Exchange {
     try {
       codec.finishRequest();
     } catch (IOException e) {
+      eventListener.requestFailed(call, e);
       trackFailure(e);
       throw e;
     }
@@ -108,6 +111,7 @@ public final class Exchange {
       }
       return result;
     } catch (IOException e) {
+      eventListener.responseFailed(call, e);
       trackFailure(e);
       throw e;
     }
@@ -126,6 +130,7 @@ public final class Exchange {
       ResponseBodySource source = new ResponseBodySource(rawSource, contentLength);
       return new RealResponseBody(contentType, contentLength, Okio.buffer(source));
     } catch (IOException e) {
+      eventListener.responseFailed(call, e);
       trackFailure(e);
       throw e;
     }
@@ -167,10 +172,18 @@ public final class Exchange {
       trackFailure(e);
     }
     if (requestDone) {
-      eventListener.requestBodyEnd(call, bytesRead);
+      if (e != null) {
+        eventListener.requestFailed(call, e);
+      } else {
+        eventListener.requestBodyEnd(call, bytesRead);
+      }
     }
     if (responseDone) {
-      eventListener.responseBodyEnd(call, bytesRead);
+      if (e != null) {
+        eventListener.responseFailed(call, e);
+      } else {
+        eventListener.responseBodyEnd(call, bytesRead);
+      }
     }
     transmitter.exchangeMessageDone(this, requestDone, responseDone, e);
   }

samples/guide/src/main/java/okhttp3/recipes/PrintEvents.java

@@ -156,6 +156,10 @@ public final class PrintEvents {
       printEvent("requestBodyEnd");
     }
 
+    @Override public void requestFailed(Call call, IOException ioe) {
+      printEvent("requestFailed");
+    }
+
     @Override public void responseHeadersStart(Call call) {
       printEvent("responseHeadersStart");
     }
@@ -172,6 +176,10 @@ public final class PrintEvents {
       printEvent("responseBodyEnd");
     }
 
+    @Override public void responseFailed(Call call, IOException ioe) {
+      printEvent("responseFailed");
+    }
+
     @Override public void callEnd(Call call) {
       printEvent("callEnd");
     }

samples/guide/src/main/java/okhttp3/recipes/PrintEventsNonConcurrent.java

@@ -131,6 +131,10 @@ public final class PrintEventsNonConcurrent {
       printEvent("requestBodyEnd");
     }
 
+    @Override public void requestFailed(Call call, IOException ioe) {
+      printEvent("requestFailed");
+    }
+
     @Override public void responseHeadersStart(Call call) {
       printEvent("responseHeadersStart");
     }
@@ -147,6 +151,10 @@ public final class PrintEventsNonConcurrent {
       printEvent("responseBodyEnd");
     }
 
+    @Override public void responseFailed(Call call, IOException ioe) {
+      printEvent("responseFailed");
+    }
+
     @Override public void callEnd(Call call) {
       printEvent("callEnd");
     }