YamlHiveCreator.java

package org.hivedb.util;

import org.hivedb.Hive;
import org.hivedb.meta.persistence.CachingDataSourceProvider;
import org.hivedb.meta.persistence.HiveDataSourceProvider;
import org.hivedb.util.database.DialectTools;
import org.hivedb.util.database.HiveDbDialect;
import org.ho.yaml.Yaml;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.List;
import java.util.Map;

/**
 * Creates a hive from a given yaml configuration file
 *
 * @author mellwanger
 */
public class YamlHiveCreator {
  private HiveDataSourceProvider dataSourceProvider = CachingDataSourceProvider.getInstance();
  private HiveDbDialect dialect;

  public YamlHiveCreator(HiveDbDialect dialect) {
    try {
      Class.forName(DialectTools.getDriver(dialect));
    } catch (Exception ex) {
      throw new RuntimeException(String.format("Error initalizing the %s server.", dialect), ex);
    }
    this.dialect = dialect;
  }

  @SuppressWarnings("unchecked")
  public Hive load(String configFile) throws FileNotFoundException {
    Map<String, Map<String, ?>> configs = (Map<String, Map<String, ?>>) Yaml.load(new FileReader(configFile));
    if (configs == null || configs.size() != 1) {
      throw new RuntimeException(String.format("Zero or multipe hives defined in %s", configFile));
    }
    return load(configs.values().iterator().next());
  }

  @SuppressWarnings("unchecked")
  private Hive load(Map<String, ?> config) {
    Map<String, String> dimension = (Map<String, String>) config.get("dimension");
    List<Map<String, ?>> nodes = (List<Map<String, ?>>) config.get("nodes");
    List<Map<String, ?>> resources = (List<Map<String, ?>>) config.get("resources");
    return new BourneHive(dimension, dataSourceProvider, dialect).addNodes(nodes).addResources(resources).getHive();
  }

  public static void main(String[] args) throws FileNotFoundException {
    if (args.length != 4 || getDialect(args) == null || getConfigFile(args) == null) {
      usage();
    } else {
      new YamlHiveCreator(getDialect(args)).load(getConfigFile(args));
    }
  }

  private static String getConfigFile(String args[]) {
    if (args[0].equalsIgnoreCase("-yml")) {
      return args[1];
    } else if (args[2].equalsIgnoreCase("-yml")) {
      return args[3];
    }
    return null;
  }

  private static HiveDbDialect getDialect(String dialect) {
    return HiveDbDialect.valueOf(dialect);
  }

  private static HiveDbDialect getDialect(String args[]) {
    if (args[0].equalsIgnoreCase("-dialect")) {
      return getDialect(args[1]);
    } else if (args[2].equalsIgnoreCase("-dialect")) {
      return getDialect(args[3]);
    }
    return null;
  }

  public static void usage() {
    System.out.println(new StringBuilder("USAGE: java -cp hivedb.jar org.hivedb.util.YamlHiveCreator -dialect [h2|mysql] -yml <path_to_yaml_config>"));
  }
}