Java tutorial
/** * Copyright (c) 2015 GoDaddy * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ package com.godaddy.logging.messagebuilders.providers; import com.godaddy.logging.CommonKeys; import com.godaddy.logging.LogContext; import com.godaddy.logging.LoggingConfigs; import com.godaddy.logging.MessageBuilder; import com.godaddy.logging.MessageBuilderProvider; import com.godaddy.logging.RunningLogContext; import com.godaddy.logging.messagebuilders.JsonContextUtils; import com.godaddy.logging.messagebuilders.JsonMessageBuilder; import net.logstash.logback.encoder.org.apache.commons.lang.StringUtils; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.stream.Collectors; import static java.util.stream.Collectors.toList; class FoldedLogData { List<Map<String, Object>> unnamed = new ArrayList<>(); List<Map<String, Object>> named = new ArrayList<>(); } public abstract class JsonMessageBuilderProvider implements MessageBuilderProvider<List<Map<String, Object>>> { @Override public MessageBuilder<List<Map<String, Object>>> getBuilder(final LoggingConfigs configs) { return new JsonMessageBuilder(configs); } protected Map<String, Object> getContextMap(final LogContext<List<Map<String, Object>>> context) { /** * Take all the log contexts that were aggregated by the message builder * and format them into a hash map. * * Take care to process duplicate keys at the top level maps (which could be a result of * multiple anonymous 'with' keywords of objects, and assign them a unique identity * * Any keys that dont' have any text will get put into a 'context' array flattened. */ final RunningLogContext<List<Map<String, Object>>> runningLogContext = JsonContextUtils .initialToRunning(context); FoldedLogData data = buildLogData(runningLogContext); HashMap<String, Object> json = new HashMap<>(); data.named.forEach(json::putAll); if (data.unnamed.size() > 0) { json.put(CommonKeys.UNNAMED_VALUES_KEY, data.unnamed.stream().flatMap(i -> i.values().stream()).collect(toList())); } return json; } private FoldedLogData buildLogData(final RunningLogContext<List<Map<String, Object>>> runningLogContext) { FoldedLogData data = new FoldedLogData(); Map<String, List<String>> keyNames = runningLogContext.getData().stream().flatMap(i -> i.keySet().stream()) .collect(Collectors.groupingBy(i -> i)); Map<String, Integer> keyCollisionIdentifier = new HashMap<>(); runningLogContext.getData().stream().forEach(withObject -> { Map<String, Object> unnamedContext = getUnnamedContext(withObject); Map<String, Object> namedContext = appendNamedContext(withObject, keyNames, keyCollisionIdentifier); if (unnamedContext.size() > 0) { data.unnamed.add(unnamedContext); } if (namedContext.size() > 0) { data.named.add(namedContext); } }); return data; } private Map<String, Object> getUnnamedContext(Map<String, Object> logContext) { Map<String, Object> unnamed = new HashMap<>(); logContext.keySet().stream().filter(key -> key.equals(StringUtils.EMPTY)) .forEach(key -> unnamed.put(key, logContext.get(key))); return unnamed; } private Map<String, Object> appendNamedContext(Map<String, Object> logContext, Map<String, List<String>> keyNames, Map<String, Integer> keyCollisionIdentifier) { Map<String, Object> named = new HashMap<>(); logContext.keySet().stream().filter(key -> !key.equals(StringUtils.EMPTY)).forEach(key -> { String name = key; /** * _unnamed_values is a reserved key for values with no key. * If a named key with the value of _unnamed_values is received, a counter value will be appended to the key name. */ if (keyNames.get(key).size() > 1 || key.equals(CommonKeys.UNNAMED_VALUES_KEY)) { if (!keyCollisionIdentifier.containsKey(key)) { keyCollisionIdentifier.put(key, 1); } Integer identity = keyCollisionIdentifier.get(key); name = identity == 1 && !key.equals(CommonKeys.UNNAMED_VALUES_KEY) ? name : (name += identity); keyCollisionIdentifier.put(key, ++identity); } named.put(name, logContext.get(key)); }); return named; } }