Tweak lang-mustache factory (#92211)

modules/lang-mustache/src/main/java/org/elasticsearch/script/mustache/CustomMustacheFactory.java

@@ -14,7 +14,9 @@
 import com.github.mustachejava.Mustache;
 import com.github.mustachejava.MustacheException;
 import com.github.mustachejava.MustacheVisitor;
+import com.github.mustachejava.SafeMustacheFactory;
 import com.github.mustachejava.TemplateContext;
+import com.github.mustachejava.TemplateFunction;
 import com.github.mustachejava.codes.DefaultMustache;
 import com.github.mustachejava.codes.IterableCode;
 import com.github.mustachejava.codes.WriteCode;
@@ -34,12 +36,11 @@
 import java.util.Map;
 import java.util.Objects;
 import java.util.StringJoiner;
-import java.util.function.Function;
 import java.util.function.Supplier;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
-public class CustomMustacheFactory extends DefaultMustacheFactory {
+public class CustomMustacheFactory extends SafeMustacheFactory {
     static final String V7_JSON_MEDIA_TYPE_WITH_CHARSET = "application/json; charset=UTF-8";
     static final String JSON_MEDIA_TYPE_WITH_CHARSET = "application/json;charset=utf-8";
     static final String JSON_MEDIA_TYPE = "application/json";
@@ -64,7 +65,7 @@ public class CustomMustacheFactory extends DefaultMustacheFactory {
     private final Encoder encoder;
 
     public CustomMustacheFactory(String mediaType) {
-        super();
+        super(Collections.emptySet(), ".");
         setObjectHandler(new CustomReflectionObjectHandler());
         this.encoder = createEncoder(mediaType);
     }
@@ -145,7 +146,7 @@ protected void tag(Writer writer, String tag) throws IOException {
             writer.write(tc.endChars());
         }
 
-        protected abstract Function<String, String> createFunction(Object resolved);
+        protected abstract TemplateFunction createFunction(Object resolved);
 
         /**
          * At compile time, this function extracts the name of the variable:
@@ -188,7 +189,7 @@ static class ToJsonCode extends CustomCode {
 
         @Override
         @SuppressWarnings("unchecked")
-        protected Function<String, String> createFunction(Object resolved) {
+        protected TemplateFunction createFunction(Object resolved) {
             return s -> {
                 if (resolved == null) {
                     return null;
@@ -238,7 +239,7 @@ static class JoinerCode extends CustomCode {
         }
 
         @Override
-        protected Function<String, String> createFunction(Object resolved) {
+        protected TemplateFunction createFunction(Object resolved) {
             return s -> {
                 if (s == null) {
                     return null;
@@ -260,7 +261,7 @@ static boolean match(String variable) {
 
     static class CustomJoinerCode extends JoinerCode {
 
-        private static final Pattern PATTERN = Pattern.compile("^(?:" + CODE + " delimiter='(.*)')$");
+        private static final Pattern PATTERN = Pattern.compile("^" + CODE + " delimiter='(.*)'$");
 
         CustomJoinerCode(TemplateContext tc, DefaultMustacheFactory df, Mustache mustache, String variable) {
             super(tc, df, mustache, extractDelimiter(variable));
@@ -357,7 +358,7 @@ static class UrlEncoder implements Encoder {
 
         @Override
         public void encode(String s, Writer writer) throws IOException {
-            writer.write(URLEncoder.encode(s, StandardCharsets.UTF_8.name()));
+            writer.write(URLEncoder.encode(s, StandardCharsets.UTF_8));
         }
     }
 }

modules/lang-mustache/src/main/java/org/elasticsearch/script/mustache/CustomReflectionObjectHandler.java

@@ -10,7 +10,6 @@
 
 import com.github.mustachejava.reflect.ReflectionObjectHandler;
 
-import org.elasticsearch.common.util.CollectionUtils;
 import org.elasticsearch.common.util.Maps;
 import org.elasticsearch.common.util.iterable.Iterables;
 
@@ -144,10 +143,4 @@ public Iterator<Object> iterator() {
             return col.iterator();
         }
     }
-
-    @Override
-    public String stringify(Object object) {
-        CollectionUtils.ensureNoSelfReferences(object, "CustomReflectionObjectHandler stringify");
-        return super.stringify(object);
-    }
 }

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/watcher/watch/Payload.java

@@ -7,6 +7,7 @@
 package org.elasticsearch.xpack.core.watcher.watch;
 
 import org.elasticsearch.common.collect.MapBuilder;
+import org.elasticsearch.common.util.CollectionUtils;
 import org.elasticsearch.xcontent.ToXContentObject;
 import org.elasticsearch.xcontent.XContentBuilder;
 
@@ -37,6 +38,7 @@ public Simple(String key, Object value) {
         }
 
         public Simple(Map<String, Object> data) {
+            CollectionUtils.ensureNoSelfReferences(data, "watcher action payload");
             this.data = data;
         }
 

x-pack/plugin/watcher/qa/rest/build.gradle

@@ -40,6 +40,7 @@ tasks.named("yamlRestTestV7CompatTransform").configure{ task ->
   task.skipTest("mustache/30_search_input/Test search input mustache integration (using request body and rest_total_hits_as_int)", "remove JodaCompatibleDateTime -- ZonedDateTime doesn't output millis/nanos if they're 0 (#78417)")
   task.skipTest("mustache/30_search_input/Test search input mustache integration (using request body)", "remove JodaCompatibleDateTime -- ZonedDateTime doesn't output millis/nanos if they're 0 (#78417)")
   task.skipTest("mustache/40_search_transform/Test search transform mustache integration (using request body)", "remove JodaCompatibleDateTime -- ZonedDateTime doesn't output millis/nanos if they're 0 (#78417)")
+  task.skipTest("painless/40_exception/Test painless exceptions are returned when logging a broken response", "Exceptions are no longer thrown from Mustache, but from the transform action itself")
   task.replaceKeyInDo("watcher.ack_watch", "xpack-watcher.ack_watch")
   task.replaceKeyInDo("watcher.activate_watch", "xpack-watcher.activate_watch")
   task.replaceKeyInDo("watcher.deactivate_watch", "xpack-watcher.deactivate_watch")

x-pack/plugin/watcher/qa/rest/src/yamlRestTest/resources/rest-api-spec/test/painless/40_exception.yml

@@ -37,6 +37,10 @@
 
 ---
 "Test painless exceptions are returned when logging a broken response":
+  - skip:
+      version: " - 8.6.99"
+      reason:  "self-referencing objects were fixed to be in Painless instead of Mustache in 8.7"
+
   - do:
       cluster.health:
           wait_for_status: green
@@ -75,36 +79,5 @@
   - match: { watch_record.trigger_event.type: "manual" }
   - match: { watch_record.state: "executed" }
   - match: { watch_record.result.actions.0.status: "failure" }
-  - match: { watch_record.result.actions.0.error.caused_by.caused_by.type: "illegal_argument_exception" }
-  - match: { watch_record.result.actions.0.error.caused_by.caused_by.reason: "Iterable object is self-referencing itself (CustomReflectionObjectHandler stringify)" }
-
-  - do:
-      catch: bad_request
-      watcher.execute_watch:
-        body: >
-          {
-            "watch": {
-              "trigger": {
-                "schedule": {
-                  "interval": "10s"
-                }
-              },
-              "input": {
-                "simple": {
-                  "foo": "bar"
-                }
-              },
-              "actions": {
-                "my-logging": {
-                  "transform": {
-                    "script": {
-                      "source": "def x = [:] ; def y = [:] ; x.a = y ; y.a = x ; return x"
-                    }
-                  },
-                  "logging": {
-                    "text": "{{#join}}ctx.payload{{/join}}"
-                  }
-                }
-              }
-            }
-          }
+  - match: { watch_record.result.actions.0.reason: "Failed to transform payload" }
+  - match: { watch_record.result.actions.0.transform.error.reason: "Iterable object is self-referencing itself (watcher action payload)" }