Github user markap14 commented on a diff in the pull request:
https://github.com/apache/nifi/pull/3198#discussion_r238848651
--- Diff:
nifi-commons/nifi-expression-language/src/main/java/org/apache/nifi/attribute/expression/language/evaluation/functions/ThreadEvaluator.java
---
@@ -0,0 +1,45 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.apache.nifi.attribute.expression.language.evaluation.functions;
+
+import java.util.Map;
+
+import org.apache.nifi.attribute.expression.language.evaluation.Evaluator;
+import
org.apache.nifi.attribute.expression.language.evaluation.QueryResult;
+import
org.apache.nifi.attribute.expression.language.evaluation.StringEvaluator;
+import
org.apache.nifi.attribute.expression.language.evaluation.StringQueryResult;
+
+public class ThreadEvaluator extends StringEvaluator {
+
+ private final StringQueryResult thread;
+
+ public ThreadEvaluator() {
+ // See org.apache.nifi.engine.FlowEngine
+ thread = new StringQueryResult(Thread.currentThread().getName());
--- End diff --
I think this needs to happen in the #evaluate method. As-is, a call to
${thread()} will result in returning the name of whatever thread created this
Evaluator, and this may not be the same thread in which it's invoked.
---
