From 8ac1b3c432a8f0ca89365cad37dfc4f21fe513c0 Mon Sep 17 00:00:00 2001
From: Jack Conradson <osjdconrad@gmail.com>
Date: Thu, 11 Sep 2025 07:28:12 -0700
Subject: [PATCH 1/2] Improve missing tranport version error message (#134506)

This updates the error message to use a "more like this"
algorithm to suggest transport versions that may exist but
are misspelled.
---
 .../org/elasticsearch/TransportVersion.java   | 23 +++++++++++++++++--
 .../elasticsearch/TransportVersionTests.java  | 21 +++++++++++++++++
 2 files changed, 42 insertions(+), 2 deletions(-)

diff --git a/server/src/main/java/org/elasticsearch/TransportVersion.java b/server/src/main/java/org/elasticsearch/TransportVersion.java
index 10641cae54e6d..4e0c28ea396fd 100644
--- a/server/src/main/java/org/elasticsearch/TransportVersion.java
+++ b/server/src/main/java/org/elasticsearch/TransportVersion.java
@@ -9,9 +9,11 @@
 
 package org.elasticsearch;
 
+import org.apache.lucene.search.spell.LevenshteinDistance;
 import org.elasticsearch.common.VersionId;
 import org.elasticsearch.common.io.stream.StreamInput;
 import org.elasticsearch.common.io.stream.StreamOutput;
+import org.elasticsearch.core.Tuple;
 import org.elasticsearch.internal.VersionExtension;
 import org.elasticsearch.plugins.ExtensionLoader;
 
@@ -234,12 +236,29 @@ public static TransportVersion fromId(int id) {
      * This will only return the latest known referable transport version for a given name and not its
      * patch versions. Patch versions are constructed as a linked list internally and may be found by
      * cycling through them in a loop using {@link TransportVersion#nextPatchVersion()}.
-     *
      */
     public static TransportVersion fromName(String name) {
         TransportVersion known = VersionsHolder.ALL_VERSIONS_BY_NAME.get(name);
         if (known == null) {
-            throw new IllegalStateException("unknown transport version [" + name + "]");
+            LevenshteinDistance ld = new LevenshteinDistance();
+            List<Tuple<Float, String>> scoredNames = new ArrayList<>();
+            for (String key : VersionsHolder.ALL_VERSIONS_BY_NAME.keySet()) {
+                float distance = ld.getDistance(name, key);
+                if (distance > 0.7f) {
+                    scoredNames.add(new Tuple<>(distance, key));
+                }
+            }
+            StringBuilder message = new StringBuilder("Unknown transport version [");
+            message.append(name);
+            message.append("].");
+            if (scoredNames.isEmpty() == false) {
+                List<String> names = scoredNames.stream().map(Tuple::v2).toList();
+                message.append(" Did you mean ");
+                message.append(names);
+                message.append("?");
+            }
+            message.append(" If this is a new transport version, run './gradle generateTransportVersion'.");
+            throw new IllegalStateException(message.toString());
         }
         return known;
     }
diff --git a/server/src/test/java/org/elasticsearch/TransportVersionTests.java b/server/src/test/java/org/elasticsearch/TransportVersionTests.java
index a197c348c9c26..52972da50f0e3 100644
--- a/server/src/test/java/org/elasticsearch/TransportVersionTests.java
+++ b/server/src/test/java/org/elasticsearch/TransportVersionTests.java
@@ -400,4 +400,25 @@ public void testComment() {
         );
         assertThat(new TransportVersion(null, 1000000, null).supports(test3), is(true));
     }
+
+    public void testMoreLikeThis() {
+        IllegalStateException ise = expectThrows(IllegalStateException.class, () -> TransportVersion.fromName("to_child_lock_join_query"));
+        assertThat(
+            ise.getMessage(),
+            is(
+                "Unknown transport version [to_child_lock_join_query]. "
+                    + "Did you mean [to_child_block_join_query]? "
+                    + "If this is a new transport version, run './gradle generateTransportVersion'."
+            )
+        );
+
+        ise = expectThrows(IllegalStateException.class, () -> TransportVersion.fromName("brand_new_version_unrelated_to_others"));
+        assertThat(
+            ise.getMessage(),
+            is(
+                "Unknown transport version [brand_new_version_unrelated_to_others]. "
+                    + "If this is a new transport version, run './gradle generateTransportVersion'."
+            )
+        );
+    }
 }

From cfc10d2c40a9e1a1269c5a39080751bafc5e15ea Mon Sep 17 00:00:00 2001
From: Jack Conradson <osjdconrad@gmail.com>
Date: Thu, 11 Sep 2025 09:32:20 -0700
Subject: [PATCH 2/2] fix tests

---
 .../org/elasticsearch/TransportVersionTests.java    | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/server/src/test/java/org/elasticsearch/TransportVersionTests.java b/server/src/test/java/org/elasticsearch/TransportVersionTests.java
index 52972da50f0e3..73ec26b631fee 100644
--- a/server/src/test/java/org/elasticsearch/TransportVersionTests.java
+++ b/server/src/test/java/org/elasticsearch/TransportVersionTests.java
@@ -402,17 +402,10 @@ public void testComment() {
     }
 
     public void testMoreLikeThis() {
-        IllegalStateException ise = expectThrows(IllegalStateException.class, () -> TransportVersion.fromName("to_child_lock_join_query"));
-        assertThat(
-            ise.getMessage(),
-            is(
-                "Unknown transport version [to_child_lock_join_query]. "
-                    + "Did you mean [to_child_block_join_query]? "
-                    + "If this is a new transport version, run './gradle generateTransportVersion'."
-            )
+        IllegalStateException ise = expectThrows(
+            IllegalStateException.class,
+            () -> TransportVersion.fromName("brand_new_version_unrelated_to_others")
         );
-
-        ise = expectThrows(IllegalStateException.class, () -> TransportVersion.fromName("brand_new_version_unrelated_to_others"));
         assertThat(
             ise.getMessage(),
             is(