samza-rest/src/main/java/org/apache/samza/rest/resources/BaseResourceConfig.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.samza.rest.resources;

import org.apache.samza.config.Config;
import org.apache.samza.config.MapConfig;
import org.apache.samza.config.factories.PropertiesConfigFactory;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;


/**
 * This class contains the common configurations that are
 * shared between different samza-rest resources.
 */
public class BaseResourceConfig extends MapConfig {

  private static final Logger LOG = LoggerFactory.getLogger(BaseResourceConfig.class);

  /**
   * Specifies the canonical name of the {@link org.apache.samza.config.ConfigFactory} to read the job configs.
   */
  public static final String CONFIG_JOB_CONFIG_FACTORY = "job.config.factory.class";

  /**
   * The path where all the Samza jobs are installed (unzipped). Each subdirectory of this path
   * is expected to be a Samza job installation and corresponds to one
   * {@link org.apache.samza.rest.proxy.installation.InstallationRecord}.
   */
  public static final String CONFIG_JOB_INSTALLATIONS_PATH = "job.installations.path";


  public BaseResourceConfig(Config config) {
    super(config);
  }

  /**
   * @see BaseResourceConfig#CONFIG_JOB_INSTALLATIONS_PATH
   * @return the path where all the Samza jobs are installed (unzipped).
   */
  public String getInstallationsPath() {
    return sanitizePath(get(CONFIG_JOB_INSTALLATIONS_PATH));
  }

  /**
   * @see BaseResourceConfig#CONFIG_JOB_INSTALLATIONS_PATH
   * @return the config factory class that has to be used to parse job configurations. If the config key
   * {@link BaseResourceConfig#CONFIG_JOB_INSTALLATIONS_PATH} is not defined, then returns the {@link PropertiesConfigFactory} class name.
   */
  public String getJobConfigFactory() {
    String configFactoryClassName = get(CONFIG_JOB_CONFIG_FACTORY);
    if (configFactoryClassName == null) {
      configFactoryClassName = PropertiesConfigFactory.class.getCanonicalName();
      LOG.warn("{} not specified. Defaulting to {}", CONFIG_JOB_CONFIG_FACTORY, configFactoryClassName);
    }
    return configFactoryClassName;
  }

  /**
   * Ensures a usable file path when the user specifies a tilde for the home path.
   *
   * @param rawPath the original path.
   * @return        the updated path with the tilde resolved to home.
   */
  private static String sanitizePath(String rawPath) {
    if (rawPath == null) {
      return null;
    }
    return rawPath.replaceFirst("^~", System.getProperty("user.home"));
  }
}