Hard exception

Author: jasontedor

core/src/main/java/org/elasticsearch/index/translog/Translog.java

@@ -1428,7 +1428,23 @@ public void prepareCommit() throws IOException {
     public void commit(final long committedGeneration) throws IOException {
         try (ReleasableLock ignored = writeLock.acquire()) {
             ensureOpen();
-            assert committedGeneration <= current.generation;
+            if (committedGeneration > current.generation) {
+                final String message = String.format(
+                        Locale.ROOT,
+                        "tried to commit generation [%d] later than the current generation [%d]",
+                        committedGeneration,
+                        current.generation);
+                throw new IllegalStateException(message);
+            }
+            final Long min = readers.stream().map(TranslogReader::getGeneration).min(Long::compareTo).orElse(Long.MIN_VALUE);
+            if (committedGeneration < min) {
+                final String message = String.format(
+                        Locale.ROOT,
+                        "tried to commit generation [%d] before minimum generation [%d]",
+                        committedGeneration,
+                        min);
+                throw new IllegalStateException(message);
+            }
             if (currentCommittingGeneration == NOT_SET_GENERATION) {
                 prepareCommit();
             }

core/src/test/java/org/elasticsearch/index/translog/TranslogTests.java

@@ -2249,6 +2249,7 @@ public void testSimpleCommit() throws IOException {
     public void testPrepareCommitAndCommit() throws IOException {
         final int operations = randomIntBetween(1, 4096);
         long seqNo = 0;
+        long last = -1;
         for (int i = 0; i < operations; i++) {
             translog.add(new Translog.NoOp(seqNo++, 0, "test"));
             if (rarely()) {
@@ -2258,7 +2259,9 @@ public void testPrepareCommitAndCommit() throws IOException {
                     // simulate generation filling up and rolling between preparing the commit and committing
                     translog.rollGeneration();
                 }
-                translog.commit(randomIntBetween(1, Math.toIntExact(generation)));
+                final int committedGeneration = randomIntBetween(Math.max(1, Math.toIntExact(last)), Math.toIntExact(generation));
+                translog.commit(committedGeneration);
+                last = committedGeneration;
                 for (long g = 0; i < generation; g++) {
                     assertFileDeleted(translog, g);
                 }