Add deprecation warnings handling to GET /index requests in tests. (#67573)

Author: astefan

qa/mixed-cluster/src/test/java/org/elasticsearch/backwards/SearchWithMinCompatibleSearchNodeIT.java

@@ -66,7 +66,7 @@ public void prepareTestData() throws IOException {
         bwcVersion = bwcNodes.get(0).getVersion();
         newVersion = newNodes.get(0).getVersion();
 
-        if (client().performRequest(new Request("HEAD", "/" + index)).getStatusLine().getStatusCode() == 404) {
+        if (indexExists(index) == false) {
             createIndex(index, Settings.builder()
                 .put(IndexMetadata.INDEX_NUMBER_OF_SHARDS_SETTING.getKey(), numShards)
                 .put(IndexMetadata.SETTING_NUMBER_OF_REPLICAS, numReplicas).build());

test/framework/src/main/java/org/elasticsearch/test/rest/ESRestTestCase.java

@@ -1252,7 +1252,14 @@ protected Map<String, Object> getIndexSettingsAsMap(String index) throws IOExcep
     }
 
     protected static boolean indexExists(String index) throws IOException {
-        Response response = client().performRequest(new Request("HEAD", "/" + index));
+        final Request getRequest = new Request("HEAD", "/" + index);
+        getRequest.setOptions(expectVersionSpecificWarnings(v -> {
+            final String typesWarning = "[types removal] The parameter include_type_name should be explicitly specified in get indices " +
+                "requests to prepare for 7.0. In 7.0 include_type_name will default to 'false', which means responses will omit the type " +
+                "name in mapping definitions.";
+            v.compatible(typesWarning);
+        }));
+        Response response = client().performRequest(getRequest);
         return RestStatus.OK.getStatus() == response.getStatusLine().getStatusCode();
     }