com.homeadvisor.kafdrop.KafDrop.java Source code

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Here is the source code for com.homeadvisor.kafdrop.KafDrop.java

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/*
 * Copyright 2016 HomeAdvisor, Inc.
 *
 * Licensed 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 com.homeadvisor.kafdrop;

import com.google.common.base.Throwables;
import com.homeadvisor.kafdrop.config.ini.IniFilePropertySource;
import com.homeadvisor.kafdrop.config.ini.IniFileReader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.actuate.autoconfigure.MetricFilterAutoConfiguration;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.event.ApplicationEnvironmentPreparedEvent;
import org.springframework.context.ApplicationListener;
import org.springframework.core.Ordered;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.Environment;

import java.io.*;
import java.util.Objects;
import java.util.stream.Stream;

@SpringBootApplication(exclude = MetricFilterAutoConfiguration.class)
public class KafDrop {
    private final static Logger LOG = LoggerFactory.getLogger(KafDrop.class);

    public static void main(String[] args) {
        new SpringApplicationBuilder(KafDrop.class).showBanner(false)
                .listeners(new EnvironmentSetupListener(), new LoggingConfigurationListener()).run(args);
    }

    private static class LoggingConfigurationListener
            implements ApplicationListener<ApplicationEnvironmentPreparedEvent>, Ordered {
        private static final String PROP_LOGGING_CONFIG = "logging.config";
        private static final String PROP_LOGGING_FILE = "logging.file";
        private static final String PROP_LOGGER = "LOGGER";
        private static final String PROP_SPRING_BOOT_LOG_LEVEL = "logging.level.org.springframework.boot";

        @Override
        public int getOrder() {
            // LoggingApplicationListener runs at HIGHEST_PRECEDENCE + 11.  This needs to run before that.
            return Ordered.HIGHEST_PRECEDENCE;
        }

        @Override
        public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
            Environment environment = event.getEnvironment();
            final String loggingFile = environment.getProperty(PROP_LOGGING_FILE);
            if (loggingFile != null) {
                System.setProperty(PROP_LOGGER, "FILE");
                try {
                    System.setProperty("logging.dir", new File(loggingFile).getParent());
                } catch (Exception ex) {
                    System.err.println("Unable to set up logging.dir from logging.file " + loggingFile + ": "
                            + Throwables.getStackTraceAsString(ex));
                }
            }
            if (environment.containsProperty("debug")
                    && !"false".equalsIgnoreCase(environment.getProperty("debug", String.class))) {
                System.setProperty(PROP_SPRING_BOOT_LOG_LEVEL, "DEBUG");
            }

        }

    }

    private static class EnvironmentSetupListener
            implements ApplicationListener<ApplicationEnvironmentPreparedEvent>, Ordered {
        private static final String SM_CONFIG_DIR = "sm.config.dir";
        private static final String CONFIG_SUFFIX = "-config.ini";

        @Override
        public int getOrder() {
            return Ordered.HIGHEST_PRECEDENCE + 10;
        }

        @Override
        public void onApplicationEvent(ApplicationEnvironmentPreparedEvent event) {
            final ConfigurableEnvironment environment = event.getEnvironment();
            if (environment.containsProperty(SM_CONFIG_DIR)) {
                Stream.of("kafdrop", "global").map(name -> readProperties(environment, name))
                        .filter(Objects::nonNull).forEach(iniPropSource -> environment.getPropertySources()
                                .addBefore("applicationConfigurationProperties", iniPropSource));
            }
        }

        private IniFilePropertySource readProperties(Environment environment, String name) {
            final File file = new File(environment.getProperty(SM_CONFIG_DIR), name + CONFIG_SUFFIX);
            if (file.exists() && file.canRead()) {
                try (InputStream in = new FileInputStream(file);
                        Reader reader = new InputStreamReader(in, "UTF-8")) {
                    return new IniFilePropertySource(name, new IniFileReader().read(reader),
                            environment.getActiveProfiles());
                } catch (IOException ex) {
                    LOG.error("Unable to read configuration file {}", file, ex);
                }
            }
            return null;
        }
    }
}