CORE: Make Pattern Exclusion Work with Aliases

* Adds the pattern exclusion logic to finding aliases
* Closes #33395

Author: original-brownbear

server/src/main/java/org/elasticsearch/cluster/metadata/MetaData.java

@@ -296,14 +296,28 @@ private ImmutableOpenMap<String, List<AliasMetaData>> findAliases(String[] origi
             return ImmutableOpenMap.of();
         }
 
-        boolean matchAllAliases = matchAllAliases(aliases);
+        List<String> includeAliases = new ArrayList<>();
+        List<String> excludeAliases = new ArrayList<>();
+        boolean wildcardSeen = false;
+        for (final String alias : aliases) {
+            if (Regex.isSimpleMatchPattern(alias)) {
+                wildcardSeen = true;
+            }
+            if (wildcardSeen && alias.charAt(0) == '-') {
+                excludeAliases.add(alias.substring(1));
+            } else {
+                includeAliases.add(alias);
+            }
+        }
+        boolean matchAllAliases = matchAllAliases(includeAliases);
         ImmutableOpenMap.Builder<String, List<AliasMetaData>> mapBuilder = ImmutableOpenMap.builder();
         for (String index : concreteIndices) {
             IndexMetaData indexMetaData = indices.get(index);
             List<AliasMetaData> filteredValues = new ArrayList<>();
             for (ObjectCursor<AliasMetaData> cursor : indexMetaData.getAliases().values()) {
                 AliasMetaData value = cursor.value;
-                if (matchAllAliases || Regex.simpleMatch(aliases, value.alias())) {
+                if ((matchAllAliases || Regex.simpleMatch(includeAliases, value.alias()))
+                    && Regex.simpleMatch(excludeAliases, value.alias()) == false) {
                     filteredValues.add(value);
                 }
             }
@@ -317,13 +331,13 @@ private ImmutableOpenMap<String, List<AliasMetaData>> findAliases(String[] origi
         return mapBuilder.build();
     }
 
-    private static boolean matchAllAliases(final String[] aliases) {
+    private static boolean matchAllAliases(final List<String> aliases) {
         for (String alias : aliases) {
             if (alias.equals(ALL)) {
                 return true;
             }
         }
-        return aliases.length == 0;
+        return aliases.isEmpty();
     }
 
     /**

server/src/test/java/org/elasticsearch/cluster/metadata/MetaDataTests.java

@@ -109,6 +109,21 @@ public void testFindAliases() {
         }
     }
 
+    public void testFindAliasWithMultiIndexAndExclusion() {
+        MetaData metaData = MetaData.builder().put(
+            IndexMetaData.builder("index")
+                .settings(Settings.builder().put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT))
+                .numberOfShards(1)
+                .numberOfReplicas(0)
+                .putAlias(AliasMetaData.builder("alias1").build())
+                .putAlias(AliasMetaData.builder("alias2").build())
+        ).build();
+        ImmutableOpenMap<String, List<AliasMetaData>> aliases =
+            metaData.findAliases(new GetAliasesRequest().aliases("*", "-alias1"), new String[] {"index"});
+        assertThat(aliases.size(), equalTo(1));
+        assertThat(aliases.get("index").get(0).alias(), equalTo("alias2"));
+    }
+
     public void testIndexAndAliasWithSameName() {
         IndexMetaData.Builder builder = IndexMetaData.builder("index")
                 .settings(Settings.builder().put(IndexMetaData.SETTING_VERSION_CREATED, Version.CURRENT))