| /** |
| * 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.pulsar.functions.api.examples; |
| |
| import org.apache.pulsar.functions.api.Context; |
| import org.apache.pulsar.functions.api.Function; |
| |
| import java.util.Optional; |
| |
| /** |
| * Function that appends something to incoming input based on config supplied. |
| */ |
| public class ConfigBasedAppendFunction implements Function<String, String> { |
| @Override |
| public String process(String input, Context context) { |
| String key = "config-key"; |
| Optional<Object> appendValue = context.getUserConfigValue(key); |
| |
| return appendValue.map(o -> input + (String) o).orElseGet(() -> input + "!"); |
| } |
| } |