kezhuw commented on code in PR #256: URL: https://github.com/apache/curator/pull/256#discussion_r1223104227
########## curator-x-discovery/src/main/java/org/apache/curator/x/discovery/DiscoveryPathConstructor.java: ########## @@ -0,0 +1,49 @@ +/* + * 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.curator.x.discovery; + +/** + * Constructs ZooKeeper paths to services for service discovering. + */ +public interface DiscoveryPathConstructor { + /** + * Return the path where all service names registered. + * + * @return the base path of all services + */ + String getBasePath(); + + /** + * Return the path where all instances of the service registered. + * + * @param serviceName service name + * @return path to service instances + */ + String getPathForInstances(String serviceName); + + /** + * Return the path where specified instance registered. + * + * @param serviceName service name + * @param instanceId instance id + * @return path to concrete instance + */ + String getPathForInstance(String serviceName, String instanceId); Review Comment: Given what the javadoc says: 1. `getPathForInstances`: Return the path where all instances of the service registered. 2. `getPathForInstance`: Return the path where specified instance registered. The second can't be an extension point to return arbitrary path. Otherwise, it violates the first. Also, I don't think this `getPathForInstance` will work. Assumes: * `getBasePath()` returns `/base-path`. * `getPathForInstances(serviceName)` returns `/base-path/{serviceName}/instances/`. Is it possible for `getPathForInstance(serviceName, instanceId)` to return paths other than `/base-path/{serviceName}/instances/{instanceId}` ? If it is possible, how should `Collection<ServiceInstance<T>> queryForInstances(String name)` be implemented ? I expect the current implementation will break. I think `getPathForInstance(serviceName, instanceId)` should behave same as `ZKPaths.makePath(getPathForInstances(serviceName), instanceId)` for this customization to function correctly. > And I'm OK to postpone this ticket unless anyone shows a real-world use case. The jira already presented a good use case from my perspective. I can continue the rest if above make sense to you and in case you are not available to push forward this. I don't think we should/can expect response from original author given his/her inactivity. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
