| /* |
| * 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.solr.update.processor; |
| |
| import java.util.ArrayList; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.function.Function; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| import org.apache.solr.common.SolrInputDocument; |
| import org.apache.solr.common.util.Cache; |
| import org.apache.solr.request.SolrQueryRequest; |
| import org.apache.solr.response.SolrQueryResponse; |
| import org.apache.solr.update.AddUpdateCommand; |
| import org.apache.solr.util.ConcurrentLRUCache; |
| |
| /** |
| * Adds new fields to documents based on a template pattern specified via Template.field |
| * request parameters (multi-valued) or 'field' value specified in initArgs. |
| * <p> |
| * The format of the parameter is <field-name>:<the-template-string>, for example: <br> |
| * <b>Template.field=fname:${somefield}some_string${someotherfield}</b> |
| * |
| * @since 6.3.0 |
| */ |
| public class TemplateUpdateProcessorFactory extends SimpleUpdateProcessorFactory { |
| private Cache<String, Resolved> templateCache = new ConcurrentLRUCache<>(1000, 800, 900, 10, false, false, null); |
| public static final String NAME = "template"; |
| @Override |
| protected void process(AddUpdateCommand cmd, SolrQueryRequest req, SolrQueryResponse rsp) { |
| String[] vals = getParams("field"); |
| SolrInputDocument doc = cmd.getSolrInputDocument(); |
| if (vals != null && vals.length > 0) { |
| for (String val : vals) { |
| if (val == null || val.isEmpty()) continue; |
| int idx = val.indexOf(':'); |
| if (idx == -1) |
| throw new RuntimeException("'field' must be of the format <field-name>:<the-template-string>"); |
| |
| String fName = val.substring(0, idx); |
| String template = val.substring(idx + 1); |
| doc.addField(fName, replaceTokens(template, templateCache, s -> { |
| Object v = doc.getFieldValue(s); |
| return v == null ? "" : v; |
| }, BRACES_PLACEHOLDER_PATTERN)); |
| } |
| } |
| |
| } |
| |
| @Override |
| protected String getMyName() { |
| return NAME; |
| } |
| |
| public static Resolved getResolved(String template, Cache<String, Resolved> cache, Pattern pattern) { |
| Resolved r = cache == null ? null : cache.get(template); |
| if (r == null) { |
| r = new Resolved(); |
| Matcher m = pattern.matcher(template); |
| while (m.find()) { |
| String variable = m.group(1); |
| r.startIndexes.add(m.start(0)); |
| r.endOffsets.add(m.end(0)); |
| r.variables.add(variable); |
| } |
| if (cache != null) cache.put(template, r); |
| } |
| return r; |
| } |
| |
| /** |
| * Get a list of variables embedded in the template string. |
| */ |
| public static List<String> getVariables(String template, Cache<String, Resolved> cache, Pattern pattern) { |
| Resolved r = getResolved(template, cache, pattern ); |
| if (r == null) { |
| return Collections.emptyList(); |
| } |
| return new ArrayList<>(r.variables); |
| } |
| |
| public static String replaceTokens(String template, Cache<String, Resolved> cache, Function<String, Object> fun, Pattern pattern) { |
| if (template == null) { |
| return null; |
| } |
| Resolved r = getResolved(template, cache, pattern); |
| if (r.startIndexes != null) { |
| StringBuilder sb = new StringBuilder(template); |
| for (int i = r.startIndexes.size() - 1; i >= 0; i--) { |
| String replacement = fun.apply(r.variables.get(i)).toString(); |
| sb.replace(r.startIndexes.get(i), r.endOffsets.get(i), replacement); |
| } |
| return sb.toString(); |
| } else { |
| return template; |
| } |
| } |
| |
| |
| public static class Resolved { |
| public List<Integer> startIndexes = new ArrayList<>(2); |
| public List<Integer> endOffsets = new ArrayList<>(2); |
| public List<String> variables = new ArrayList<>(2); |
| } |
| |
| public static final Pattern DOLLAR_BRACES_PLACEHOLDER_PATTERN = Pattern |
| .compile("[$][{](.*?)[}]"); |
| public static final Pattern BRACES_PLACEHOLDER_PATTERN = Pattern |
| .compile("[{](.*?)[}]"); |
| } |