| /** |
| * 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.camel.component.properties; |
| |
| import java.util.Locale; |
| |
| import org.apache.camel.util.StringHelper; |
| |
| /** |
| * A {@link PropertiesFunction} that lookup the property value from |
| * OS environment variables using the service idiom. |
| * <p/> |
| * A service is defined using two environment variables where name is name of the service: |
| * <ul> |
| * <li><tt>NAME_SERVICE_HOST</tt></li> |
| * <li><tt>NAME_SERVICE_PORT</tt></li> |
| * </ul> |
| * in other words the service uses <tt>_SERVICE_HOST</tt> and <tt>_SERVICE_PORT</tt> as prefix. |
| * <p/> |
| * This implementation is to return the host part only. |
| * |
| * @see ServicePropertiesFunction |
| * @see ServicePortPropertiesFunction |
| */ |
| public class ServiceHostPropertiesFunction implements PropertiesFunction { |
| |
| private static final String HOST_PREFIX = "_SERVICE_HOST"; |
| |
| @Override |
| public String getName() { |
| return "service.host"; |
| } |
| |
| @Override |
| public String apply(String remainder) { |
| String key = remainder; |
| String defaultValue = null; |
| |
| if (remainder.contains(":")) { |
| key = StringHelper.before(remainder, ":"); |
| defaultValue = StringHelper.after(remainder, ":"); |
| } |
| |
| // make sure to use upper case |
| if (key != null) { |
| // make sure to use underscore as dash is not supported as ENV variables |
| key = key.toUpperCase(Locale.ENGLISH).replace('-', '_'); |
| |
| // a service should have both the host and port defined |
| String host = System.getenv(key + HOST_PREFIX); |
| |
| if (host != null) { |
| return host; |
| } else { |
| return defaultValue; |
| } |
| } |
| |
| return defaultValue; |
| } |
| } |
| |