org.apache.druid.segment.loading.URIDataPuller Maven / Gradle / Ivy

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A module that is everything required to understands Druid Segments

There is a newer version: 31.0.0

/*
 * 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.druid.segment.loading;

import com.google.common.base.Predicate;
import org.apache.druid.guice.annotations.ExtensionPoint;

import java.io.IOException;
import java.io.InputStream;
import java.net.URI;

/**
 * A URIDataPuller has handlings for URI based data
 */
@ExtensionPoint
public interface URIDataPuller
{
  /**
   * Create a new InputStream based on the URI
   *
   * @param uri The URI to open an Input Stream to
   *
   * @return A new InputStream which streams the URI in question
   *
   * @throws IOException
   */
  InputStream getInputStream(URI uri) throws IOException;

  /**
   * Returns an abstract "version" for the URI. The exact meaning of the version is left up to the implementation.
   *
   * @param uri The URI to check
   *
   * @return A "version" as interpreted by the URIDataPuller implementation
   *
   * @throws IOException on error
   */
  String getVersion(URI uri) throws IOException;

  /**
   * Evaluates a Throwable to see if it is recoverable. This is expected to be used in conjunction with the other methods
   * to determine if anything thrown from the method should be retried.
   *
   * @return Predicate function indicating if the Throwable is recoverable
   */
  Predicate shouldRetryPredicate();
}