io.cdap.cdap.internal.bootstrap.FileBootstrapConfigProvider Maven / Gradle / Ivy
/*
* Copyright © 2018 Cask Data, 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 io.cdap.cdap.internal.bootstrap;
import com.google.gson.Gson;
import com.google.gson.JsonParseException;
import com.google.inject.Inject;
import io.cdap.cdap.common.conf.CConfiguration;
import io.cdap.cdap.common.conf.Constants;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;
/**
* Reads the bootstrap config from a file. If there was an error reading the file, no bootstrapping will be
* performed. If the file does not exist, the default bootstrap steps will be executed.
*/
public class FileBootstrapConfigProvider implements BootstrapConfigProvider {
private static final Logger LOG = LoggerFactory.getLogger(FileBootstrapConfigProvider.class);
private static final Gson GSON = new Gson();
private final File bootstrapFile;
@Inject
FileBootstrapConfigProvider(CConfiguration cConf) {
this.bootstrapFile = new File(cConf.get(Constants.BOOTSTRAP_FILE));
}
@Override
public BootstrapConfig getConfig() {
try {
try (Reader reader = new FileReader(bootstrapFile)) {
return GSON.fromJson(reader, BootstrapConfig.class);
}
} catch (FileNotFoundException e) {
LOG.info("Bootstrap file {} does not exist. Default bootstrapping will be done.",
bootstrapFile.getAbsolutePath());
return BootstrapConfig.DEFAULT;
} catch (JsonParseException e) {
LOG.warn("Could not parse bootstrap file {}. No bootstrapping will be done.",
bootstrapFile.getAbsolutePath(), e);
return BootstrapConfig.EMPTY;
} catch (IOException e) {
LOG.warn("Could not read bootstrap file {}. No bootstrapping will be done.",
bootstrapFile.getAbsolutePath(), e);
return BootstrapConfig.EMPTY;
}
}
}