1 // Copyright 2021 Google LLC 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 package com.google.api.generator.gapic.utils; 16 17 import java.util.Arrays; 18 import java.util.Optional; 19 20 public final class ResourceReferenceUtils { 21 22 private static final String SLASH = "/"; 23 ResourceReferenceUtils()24 private ResourceReferenceUtils() {} 25 parseParentPattern(String pattern)26 public static Optional<String> parseParentPattern(String pattern) { 27 String[] tokens = pattern.split(SLASH); 28 String lastToken = tokens[tokens.length - 1]; 29 if (lastToken.equals(ResourceNameConstants.DELETED_TOPIC_LITERAL) 30 || lastToken.equals(ResourceNameConstants.WILDCARD_PATTERN)) { 31 return Optional.empty(); 32 } 33 34 int lastTokenIndex = tokens.length - 2; 35 int minLengthWithParent = 4; 36 // Singleton patterns, e.g. projects/{project}/agent. 37 if (!lastToken.contains("{")) { 38 minLengthWithParent = 3; 39 lastTokenIndex = tokens.length - 1; 40 } 41 42 // No fully-formed parent. Expected: ancestors/{ancestor}/childNodes/{child_node}. 43 if (tokens.length < minLengthWithParent) { 44 return Optional.empty(); 45 } 46 47 return Optional.of(String.join(SLASH, Arrays.asList(tokens).subList(0, lastTokenIndex))); 48 } 49 } 50