DynamicCodec emits a trail of type names when it encounters NoSuchCod…

…ecException. This will make it easier to trace down missing codecs. PiperOrigin-RevId: 191920743
agoulti · Apr 6, 2018 · e4c64ac · e4c64ac
1 parent 4282c19
commit e4c64ac
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Showing 3 changed files with 54 additions and 1 deletion.
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/serialization/DynamicCodec.java b/src/main/java/com/google/devtools/build/lib/skyframe/serialization/DynamicCodec.java
@@ -123,7 +123,12 @@ private void serializeField(
         serializeField(context, codedOut, arr, type.getComponentType(), base + scale * i);
       }
     } else {
-      context.serialize(UnsafeProvider.getInstance().getObject(obj, offset), codedOut);
+      try {
+        context.serialize(UnsafeProvider.getInstance().getObject(obj, offset), codedOut);
+      } catch (SerializationException.NoCodecException e) {
+        e.addTrail(this.type);
+        throw e;
+      }
     }
   }
 

diff --git a/...ain/java/com/google/devtools/build/lib/skyframe/serialization/SerializationException.java b/...ain/java/com/google/devtools/build/lib/skyframe/serialization/SerializationException.java
@@ -15,6 +15,7 @@
 package com.google.devtools.build.lib.skyframe.serialization;
 
 import java.io.NotSerializableException;
+import java.util.ArrayList;
 
 /** Exception signaling a failure to Serialize or Deserialize an Object. */
 public class SerializationException extends Exception {
@@ -35,6 +36,8 @@ public SerializationException(String msg, Throwable cause) {
    * or type of object.
    */
   public static class NoCodecException extends SerializationException {
+    ArrayList<String> trail = new ArrayList<>();
+
     NoCodecException(String message) {
       super(message);
     }
@@ -51,6 +54,20 @@ public static class NoCodecException extends SerializationException {
     NoCodecException(String message, NoCodecException e) {
       super(message, e);
     }
+
+    @Override
+    public String getMessage() {
+      return super.getMessage() + (trail.isEmpty() ? "" : " " + trail);
+    }
+
+    /**
+     * Adds extra tracing info for debugging.
+     *
+     * <p>Primarily useful for {@link DynamicCodec}.
+     */
+    public void addTrail(Class<?> type) {
+      trail.add(type.getName());
+    }
   }
 
   /**

diff --git a/src/test/java/com/google/devtools/build/lib/skyframe/serialization/DynamicCodecTest.java b/src/test/java/com/google/devtools/build/lib/skyframe/serialization/DynamicCodecTest.java
@@ -15,8 +15,11 @@
 package com.google.devtools.build.lib.skyframe.serialization;
 
 import static com.google.common.truth.Truth.assertThat;
+import static org.junit.Assert.fail;
 
+import com.google.common.collect.ImmutableMap;
 import com.google.devtools.build.lib.skyframe.serialization.testutils.SerializationTester;
+import java.io.BufferedInputStream;
 import java.util.Arrays;
 import java.util.Objects;
 import org.junit.Test;
@@ -371,4 +374,32 @@ public void testPrimitiveExample() throws Exception {
         .setRepetitions(100000)
         .runTests();
   }
+
+  private static class NoCodecExample2 {
+    @SuppressWarnings("unused")
+    private final BufferedInputStream noCodec = new BufferedInputStream(null);
+  }
+
+  private static class NoCodecExample1 {
+    @SuppressWarnings("unused")
+    private final NoCodecExample2 noCodec = new NoCodecExample2();
+  }
+
+  @Test
+  public void testNoCodecExample() throws Exception {
+    ObjectCodecs codecs = new ObjectCodecs(AutoRegistry.get(), ImmutableMap.of());
+    try {
+      codecs.serializeMemoized(new NoCodecExample1());
+      fail();
+    } catch (SerializationException.NoCodecException expected) {
+      assertThat(expected)
+          .hasMessageThat()
+          .contains(
+              "java.io.BufferedInputStream ["
+                  + "com.google.devtools.build.lib.skyframe.serialization."
+                  + "DynamicCodecTest$NoCodecExample2, "
+                  + "com.google.devtools.build.lib.skyframe.serialization."
+                  + "DynamicCodecTest$NoCodecExample1]");
+    }
+  }
 }