Add commandIndex to mismatch exceptions (#518)

Author: slinkydeveloper

sdk-core/src/main/java/dev/restate/sdk/core/statemachine/CommandAccessor.java

@@ -16,7 +16,7 @@ interface CommandAccessor<E extends MessageLite> {
 
   String getName(E expected);
 
-  void checkEntryHeader(E expected, MessageLite actual) throws ProtocolException;
+  void checkEntryHeader(int commandIndex, E expected, MessageLite actual) throws ProtocolException;
 
   CommandAccessor<Protocol.InputCommandMessage> INPUT =
       new CommandAccessor<>() {
@@ -26,7 +26,8 @@ public String getName(Protocol.InputCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.InputCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.InputCommandMessage expected, MessageLite actual)
             throws ProtocolException {
           // Nothing to check
         }
@@ -39,9 +40,11 @@ public String getName(Protocol.OutputCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.OutputCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.OutputCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.OutputCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.OutputCommandMessage.class, expected, actual)
               .checkField("name", Protocol.OutputCommandMessage::getName)
               .checkField("result", Protocol.OutputCommandMessage::getResultCase)
               .checkField("value", Protocol.OutputCommandMessage::getValue)
@@ -53,9 +56,10 @@ public void checkEntryHeader(Protocol.OutputCommandMessage expected, MessageLite
       new CommandAccessor<>() {
         @Override
         public void checkEntryHeader(
-            Protocol.GetEagerStateCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.GetEagerStateCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.GetEagerStateCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.GetEagerStateCommandMessage.class, expected, actual)
               .checkField("name", Protocol.GetEagerStateCommandMessage::getName)
               .checkField("key", Protocol.GetEagerStateCommandMessage::getKey)
               .verify();
@@ -75,9 +79,10 @@ public String getName(Protocol.GetLazyStateCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.GetLazyStateCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.GetLazyStateCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.GetLazyStateCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.GetLazyStateCommandMessage.class, expected, actual)
               .checkField("name", Protocol.GetLazyStateCommandMessage::getName)
               .checkField("key", Protocol.GetLazyStateCommandMessage::getKey)
               .checkField(
@@ -95,9 +100,10 @@ public String getName(Protocol.GetEagerStateKeysCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.GetEagerStateKeysCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.GetEagerStateKeysCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.GetEagerStateKeysCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.GetEagerStateKeysCommandMessage.class, expected, actual)
               .checkField("name", Protocol.GetEagerStateKeysCommandMessage::getName)
               .verify();
         }
@@ -111,9 +117,10 @@ public String getName(Protocol.GetLazyStateKeysCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.GetLazyStateKeysCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.GetLazyStateKeysCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.GetLazyStateKeysCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.GetLazyStateKeysCommandMessage.class, expected, actual)
               .checkField("name", Protocol.GetLazyStateKeysCommandMessage::getName)
               .verify();
         }
@@ -126,9 +133,11 @@ public String getName(Protocol.ClearStateCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.ClearStateCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.ClearStateCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.ClearStateCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.ClearStateCommandMessage.class, expected, actual)
               .checkField("name", Protocol.ClearStateCommandMessage::getName)
               .checkField("key", Protocol.ClearStateCommandMessage::getKey)
               .verify();
@@ -143,9 +152,10 @@ public String getName(Protocol.ClearAllStateCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.ClearAllStateCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.ClearAllStateCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.ClearAllStateCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.ClearAllStateCommandMessage.class, expected, actual)
               .checkField("name", Protocol.ClearAllStateCommandMessage::getName)
               .verify();
         }
@@ -158,9 +168,11 @@ public String getName(Protocol.SetStateCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.SetStateCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.SetStateCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.SetStateCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.SetStateCommandMessage.class, expected, actual)
               .checkField("name", Protocol.SetStateCommandMessage::getName)
               .checkField("key", Protocol.SetStateCommandMessage::getKey)
               .checkField("value", Protocol.SetStateCommandMessage::getValue)
@@ -176,9 +188,11 @@ public String getName(Protocol.SleepCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.SleepCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.SleepCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.SleepCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.SleepCommandMessage.class, expected, actual)
               .checkField("name", Protocol.SleepCommandMessage::getName)
               .checkField(
                   "result_completion_id", Protocol.SleepCommandMessage::getResultCompletionId)
@@ -194,9 +208,11 @@ public String getName(Protocol.CallCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.CallCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.CallCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.CallCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.CallCommandMessage.class, expected, actual)
               .checkField("name", Protocol.CallCommandMessage::getName)
               .checkField("service_name", Protocol.CallCommandMessage::getServiceName)
               .checkField("handler_name", Protocol.CallCommandMessage::getHandlerName)
@@ -220,9 +236,11 @@ public String getName(Protocol.OneWayCallCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.OneWayCallCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.OneWayCallCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.OneWayCallCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.OneWayCallCommandMessage.class, expected, actual)
               .checkField("name", Protocol.OneWayCallCommandMessage::getName)
               .checkField("service_name", Protocol.OneWayCallCommandMessage::getServiceName)
               .checkField("handler_name", Protocol.OneWayCallCommandMessage::getHandlerName)
@@ -246,9 +264,10 @@ public String getName(Protocol.CompleteAwakeableCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.CompleteAwakeableCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.CompleteAwakeableCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.CompleteAwakeableCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.CompleteAwakeableCommandMessage.class, expected, actual)
               .checkField("name", Protocol.CompleteAwakeableCommandMessage::getName)
               .checkField("awakeable_id", Protocol.CompleteAwakeableCommandMessage::getAwakeableId)
               .checkField("result", Protocol.CompleteAwakeableCommandMessage::getResultCase)
@@ -265,9 +284,10 @@ public String getName(Protocol.RunCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.RunCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.RunCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.RunCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(commandIndex, Protocol.RunCommandMessage.class, expected, actual)
               .checkField("name", Protocol.RunCommandMessage::getName)
               .verify();
         }
@@ -281,9 +301,11 @@ public String getName(Protocol.GetPromiseCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.GetPromiseCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.GetPromiseCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.GetPromiseCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.GetPromiseCommandMessage.class, expected, actual)
               .checkField("name", Protocol.GetPromiseCommandMessage::getName)
               .checkField("key", Protocol.GetPromiseCommandMessage::getKey)
               .checkField(
@@ -300,9 +322,10 @@ public String getName(Protocol.PeekPromiseCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.PeekPromiseCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.PeekPromiseCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.PeekPromiseCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.PeekPromiseCommandMessage.class, expected, actual)
               .checkField("name", Protocol.PeekPromiseCommandMessage::getName)
               .checkField("key", Protocol.PeekPromiseCommandMessage::getKey)
               .checkField(
@@ -319,9 +342,10 @@ public String getName(Protocol.CompletePromiseCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.CompletePromiseCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.CompletePromiseCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.CompletePromiseCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.CompletePromiseCommandMessage.class, expected, actual)
               .checkField("name", Protocol.CompletePromiseCommandMessage::getName)
               .checkField("key", Protocol.CompletePromiseCommandMessage::getKey)
               .checkField(
@@ -344,9 +368,11 @@ public String getName(Protocol.SendSignalCommandMessage expected) {
         }
 
         @Override
-        public void checkEntryHeader(Protocol.SendSignalCommandMessage expected, MessageLite actual)
+        public void checkEntryHeader(
+            int commandIndex, Protocol.SendSignalCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.SendSignalCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.SendSignalCommandMessage.class, expected, actual)
               .checkField("entry_name", Protocol.SendSignalCommandMessage::getEntryName)
               .checkField(
                   "target_invocation_id", Protocol.SendSignalCommandMessage::getTargetInvocationId)
@@ -368,9 +394,10 @@ public String getName(Protocol.AttachInvocationCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.AttachInvocationCommandMessage expected, MessageLite actual)
+            int commandIndex, Protocol.AttachInvocationCommandMessage expected, MessageLite actual)
             throws ProtocolException {
-          EntryHeaderChecker.check(Protocol.AttachInvocationCommandMessage.class, expected, actual)
+          EntryHeaderChecker.check(
+                  commandIndex, Protocol.AttachInvocationCommandMessage.class, expected, actual)
               .checkField("name", Protocol.AttachInvocationCommandMessage::getName)
               .checkField("invocation_id", Protocol.AttachInvocationCommandMessage::getInvocationId)
               .checkField(
@@ -389,10 +416,12 @@ public String getName(Protocol.GetInvocationOutputCommandMessage expected) {
 
         @Override
         public void checkEntryHeader(
-            Protocol.GetInvocationOutputCommandMessage expected, MessageLite actual)
+            int commandIndex,
+            Protocol.GetInvocationOutputCommandMessage expected,
+            MessageLite actual)
             throws ProtocolException {
           EntryHeaderChecker.check(
-                  Protocol.GetInvocationOutputCommandMessage.class, expected, actual)
+                  commandIndex, Protocol.GetInvocationOutputCommandMessage.class, expected, actual)
               .checkField("name", Protocol.GetInvocationOutputCommandMessage::getName)
               .checkField(
                   "invocation_id", Protocol.GetInvocationOutputCommandMessage::getInvocationId)

sdk-core/src/main/java/dev/restate/sdk/core/statemachine/EntryHeaderChecker.java

@@ -23,38 +23,43 @@
  * exceptions when mismatches are found.
  */
 final class EntryHeaderChecker<E extends MessageLite> {
+  private final int commandIndex;
   private final E expected;
   private final E actual;
   private List<FieldMismatch> mismatches;
 
-  private EntryHeaderChecker(E expected, E actual) {
+  private EntryHeaderChecker(int commandIndex, E expected, E actual) {
+    this.commandIndex = commandIndex;
     this.expected = expected;
     this.actual = actual;
   }
 
   /**
    * Creates a new EntryHeaderChecker for the given expected and actual messages.
    *
+   * @param <E> The type of the expected message
+   * @param commandIndex The index of this command
    * @param expected The expected message
    * @param actual The actual message
-   * @param <E> The type of the expected message
    * @return A new EntryHeaderChecker
    */
   @SuppressWarnings("unchecked")
   public static <E extends MessageLite> EntryHeaderChecker<E> check(
-      Class<E> expectedClass, E expected, MessageLite actual) {
+      int commandIndex, Class<E> expectedClass, E expected, MessageLite actual) {
     if (!expectedClass.isInstance(actual)) {
       throw new ProtocolException(
           "Found a mismatch between the code paths taken during the previous execution and the paths taken during this execution.\n"
               + "This typically happens when some parts of the code are non-deterministic.\n"
               + "- Expecting command '"
               + Util.commandMessageToString(expected)
-              + "' but was '"
+              + "' (index "
+              + commandIndex
+              + ") but was '"
               + Util.commandMessageToString(actual)
               + "'",
           JOURNAL_MISMATCH_CODE);
     }
-    return new EntryHeaderChecker<>(expected, (E) actual);
+    return new EntryHeaderChecker<>(commandIndex, expected, (E) actual);
   }
 
   /**
@@ -97,7 +102,9 @@ private ProtocolException createMismatchException() {
                 + "This typically happens when some parts of the code are non-deterministic.\n"
                 + "- The mismatch happened while executing '"
                 + Util.commandMessageToString(expected)
-                + "'\n"
+                + " (index "
+                + commandIndex
+                + ")'\n"
                 + "- Difference:");
     for (FieldMismatch mismatch : mismatches) {
       customMessage