001/*
002 * (C) Copyright 2017 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     bdelbosc
018 */
019package org.nuxeo.lib.stream.tools.command;
020
021import static org.nuxeo.lib.stream.tools.command.CatCommand.NUXEO_SCHEMA_STORE;
022
023import java.nio.file.Paths;
024import java.time.Duration;
025
026import org.apache.commons.cli.CommandLine;
027import org.apache.commons.cli.Option;
028import org.apache.commons.cli.Options;
029import org.apache.commons.logging.Log;
030import org.apache.commons.logging.LogFactory;
031import org.nuxeo.lib.stream.computation.Record;
032import org.nuxeo.lib.stream.log.LogManager;
033import org.nuxeo.lib.stream.log.LogRecord;
034import org.nuxeo.lib.stream.log.LogTailer;
035import org.nuxeo.lib.stream.log.Name;
036import org.nuxeo.lib.stream.tools.renderer.Renderer;
037
038/**
039 * Output the last records on a Log.
040 *
041 * @since 9.3
042 */
043public class TailCommand extends Command {
044    private static final Log log = LogFactory.getLog(TailCommand.class);
045
046    protected static final String NAME = "tail";
047
048    @Override
049    public String name() {
050        return NAME;
051    }
052
053    @Override
054    public void updateOptions(Options options) {
055        options.addOption(Option.builder("n")
056                                .longOpt("lines")
057                                .desc("output the last NUM records")
058                                .hasArg()
059                                .argName("NUM")
060                                .build());
061        options.addOption("f", "follow", false, "output appended records");
062        options.addOption(Option.builder("l")
063                                .longOpt("log-name")
064                                .desc("Log name")
065                                .required()
066                                .hasArg()
067                                .argName("LOG_NAME")
068                                .build());
069        options.addOption(
070                Option.builder("g").longOpt("group").desc("Consumer group").hasArg().argName("GROUP").build());
071        options.addOption(Option.builder()
072                                .longOpt("codec")
073                                .desc("Codec used to read record, can be: java, avro, avroBinary, avroJson")
074                                .hasArg()
075                                .argName("CODEC")
076                                .build());
077        options.addOption(Option.builder()
078                                .longOpt("data-size")
079                                .desc("Maximum size of message data to render")
080                                .hasArg()
081                                .argName("L")
082                                .build());
083        options.addOption(
084                Option.builder().longOpt("render").desc("Output rendering").hasArg().argName("FORMAT").build());
085        options.addOption(Option.builder("t")
086                                .longOpt("timeout")
087                                .desc("Timeout on follow in second")
088                                .hasArg()
089                                .argName("TIMEOUT")
090                                .build());
091        options.addOption(Option.builder()
092                                .longOpt("schema-store")
093                                .desc("Set path of a FileAvroSchemaStore to load Avro schemas")
094                                .hasArg()
095                                .argName("SCHEMA_STORE_PATH")
096                                .build());
097    }
098
099    @Override
100    public boolean run(LogManager manager, CommandLine cmd) throws InterruptedException {
101        int lines = Integer.parseInt(cmd.getOptionValue("lines", "10"));
102        int dataSize = Integer.parseInt(cmd.getOptionValue("data-size", "256"));
103        Name name = Name.ofUrn(cmd.getOptionValue("log-name"));
104        String render = cmd.getOptionValue("render", "default");
105        Name group = Name.ofUrn(cmd.getOptionValue("group", "admin/tools"));
106        String codec = cmd.getOptionValue("codec");
107        String avroSchemaStorePath = cmd.getOptionValue("schema-store");
108        if (avroSchemaStorePath == null && Paths.get(NUXEO_SCHEMA_STORE).toFile().exists()) {
109            avroSchemaStorePath = NUXEO_SCHEMA_STORE;
110        }
111        int timeout = Integer.parseInt(cmd.getOptionValue("timeout", "120"));
112        tail(manager, name, group, lines, getRecordRenderer(render, avroSchemaStorePath, dataSize), codec);
113        if (cmd.hasOption("follow")) {
114            follow(manager, name, group, getRecordRenderer(render, avroSchemaStorePath, dataSize), timeout, codec);
115        }
116        return true;
117    }
118
119    @SuppressWarnings("unchecked")
120    protected void tail(LogManager manager, Name name, Name group, int lines, Renderer render, String codec)
121            throws InterruptedException {
122        LogRecord<Record>[] records = new LogRecord[lines];
123        render.header();
124        int count = 0;
125        try (LogTailer<Record> tailer = manager.createTailer(group, name, getRecordCodec(codec))) {
126            LogRecord<Record> record;
127            do {
128                record = tailer.read(Duration.ofMillis(500));
129                if (record != null) {
130                    records[count++ % lines] = record;
131                }
132            } while (record != null);
133        }
134        for (int i = count; i < lines + count; i++) {
135            LogRecord<Record> record = records[i % lines];
136            if (record != null) {
137                render.accept(record);
138            }
139        }
140        render.footer();
141    }
142
143    protected void follow(LogManager manager, Name name, Name group, Renderer render, int timeout, String codec)
144            throws InterruptedException {
145        try (LogTailer<Record> tailer = manager.createTailer(group, name, getRecordCodec(codec))) {
146            tailer.toEnd();
147            while (true) {
148                LogRecord<Record> record = tailer.read(Duration.ofSeconds(timeout));
149                if (record == null) {
150                    log.error("tail timeout");
151                    break;
152                }
153                render.accept(record);
154            }
155        }
156    }
157}