FilePropertyLoader.java
/*
* Copyright (c) 2019, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
*
* 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 org.apache.synapse.commons.util;
import com.google.common.util.concurrent.ThreadFactoryBuilder;
import org.apache.commons.lang.StringUtils;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.synapse.commons.SynapseCommonsException;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Objects;
import java.util.Properties;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
/**
* File Property loader can be used to load the file property variables.
*/
public class FilePropertyLoader {
private static final Log LOG = LogFactory.getLog(FilePropertyLoader.class);
private static final String CONF_LOCATION = "conf.location";
private static final String FILE_PROPERTY_PATH = "properties.file.path";
private static final String DEFAULT_PROPERTY_FILE = "file.properties";
private static final String FILE_SYNC_INTERVAL = "file.properties.sync.interval";
private static final String FILE_CANNOT_BE_FOUND_ERROR = "File cannot found in ";
private String propertiesFilePath;
private long lastModifiedTimestamp;
private Map<String, String> propertyMap;
private static FilePropertyLoader fileLoaderInstance;
private FilePropertyLoader() {
init();
loadPropertiesFile();
String fileSyncIntervalString = System.getProperty(FILE_SYNC_INTERVAL);
if (StringUtils.isNotEmpty(fileSyncIntervalString)) {
try {
int syncInterval = Integer.parseInt(fileSyncIntervalString);
if (syncInterval > 0) {
if (LOG.isDebugEnabled()) {
LOG.debug("File syncing enabled with interval " + syncInterval);
}
Executors.newSingleThreadScheduledExecutor(
new ThreadFactoryBuilder().setNameFormat("FilePropertySyncTask-%d").build())
.scheduleAtFixedRate(
() -> {
try {
loadPropertiesFile();
if (LOG.isDebugEnabled()) {
LOG.debug("File property sync task completed");
}
} catch (Exception e) {
LOG.error("Error while syncing properties file ", e);
}
}, syncInterval, syncInterval, TimeUnit.SECONDS);
}
} catch (NumberFormatException e) {
LOG.warn("Dropping system property " + FILE_SYNC_INTERVAL + " with incorrect value specified. File "
+ "property syncing will be disabled. ");
}
}
}
public static FilePropertyLoader getInstance() {
if (Objects.nonNull(fileLoaderInstance)) {
return fileLoaderInstance;
}
synchronized (FilePropertyLoader.class) {
if (Objects.isNull(fileLoaderInstance)) {
fileLoaderInstance = new FilePropertyLoader();
}
return fileLoaderInstance;
}
}
public String getValue(String input) {
return propertyMap.get(input);
}
private void loadPropertiesFile() throws SynapseCommonsException {
File file = new File(propertiesFilePath);
if (file.exists()) {
if (file.lastModified() > lastModifiedTimestamp) {
try (InputStream in = new FileInputStream(propertiesFilePath)) {
Properties rawProps = new Properties();
Map<String, String> tempPropertyMap = new HashMap<>();
rawProps.load(in);
for (Map.Entry<Object, Object> propertyEntry : rawProps.entrySet()) {
String strValue = (String) propertyEntry.getValue();
tempPropertyMap.put((String) propertyEntry.getKey(), strValue);
}
propertyMap = tempPropertyMap;
lastModifiedTimestamp = file.lastModified();
if (LOG.isDebugEnabled()) {
LOG.debug("Synced properties from " + propertiesFilePath);
}
} catch (IOException ex) {
throw new SynapseCommonsException("Failed to read " + propertiesFilePath, ex);
}
}
} else {
throw new SynapseCommonsException(FILE_CANNOT_BE_FOUND_ERROR + propertiesFilePath);
}
}
private void init() {
String filePath = System.getProperty(FILE_PROPERTY_PATH);
if (null == filePath || filePath.isEmpty()) {
throw new SynapseCommonsException(FILE_PROPERTY_PATH + " is empty or null");
}
if (("default").equals(filePath)) {
propertiesFilePath = System.getProperty(CONF_LOCATION) + File.separator + DEFAULT_PROPERTY_FILE;
} else {
propertiesFilePath = filePath;
}
File file = new File(propertiesFilePath);
if (!file.exists()) {
throw new SynapseCommonsException(FILE_CANNOT_BE_FOUND_ERROR + filePath);
}
propertyMap = new HashMap<>();
}
}