nl.kpmg.lcm.server.data.s3.S3FileSystemAdapter.java Source code

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Here is the source code for nl.kpmg.lcm.server.data.s3.S3FileSystemAdapter.java

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package nl.kpmg.lcm.server.data.s3;

import com.amazonaws.auth.AWSCredentials;
import com.amazonaws.auth.AWSStaticCredentialsProvider;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3ClientBuilder;
import com.amazonaws.services.s3.model.ObjectListing;
import com.amazonaws.services.s3.model.S3ObjectSummary;

import nl.kpmg.lcm.common.data.TestResult;
import nl.kpmg.lcm.server.backend.storage.S3FileStorage;
import nl.kpmg.lcm.server.data.FileSystemAdapter;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.util.LinkedList;
import java.util.List;

/*
  * Copyright 2017 KPMG N.V. (unless otherwise stated).
  *
  * 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.
 */

/**
 *
 * @author shristov
 */
public class S3FileSystemAdapter implements FileSystemAdapter {
    //private final S3FileStorage storage;
    private static final org.slf4j.Logger LOGGER = LoggerFactory.getLogger(S3FileAdapter.class.getName());
    private String bucketName;

    private AmazonS3 s3Client;
    private String fileName;

    public S3FileSystemAdapter(S3FileStorage s3Storage) {
        String secretAcccessKey;
        secretAcccessKey = s3Storage.getAwsSecretAccessKey();

        AWSCredentials credentials = new BasicAWSCredentials(s3Storage.getAwsAccessKey(), secretAcccessKey);
        AWSStaticCredentialsProvider credentialsProvider = new AWSStaticCredentialsProvider(credentials);
        s3Client = AmazonS3ClientBuilder.standard().withCredentials(credentialsProvider)
                .withRegion(Regions.EU_WEST_1).build();

        bucketName = s3Storage.getBucketName();
    }

    @Override
    public List listFileNames(String subPath) throws IOException {

        if (subPath.length() > 0 && subPath.charAt(subPath.length() - 1) != '/') {
            subPath = subPath + '/';
        }

        LinkedList<String> fileNameList = new LinkedList();
        ObjectListing listing;
        do {
            listing = s3Client.listObjects(bucketName, subPath);
            List<S3ObjectSummary> objectSummaryList = listing.getObjectSummaries();

            for (S3ObjectSummary objectSummary : objectSummaryList) {
                String key = objectSummary.getKey();
                int index = StringUtils.lastIndexOf(key, "/");
                // Some of the keys contain '/'. For example "test/test1.csv". Some others don`t. For
                // example "example1.txt". If a key doesn`t contain '/' the value of index would be -1. That
                // is why we need the following check.
                if (index == -1) {
                    index = 0;
                }
                String itemName = key.substring(index);
                fileNameList.add(itemName);
            }
        } while (listing.isTruncated());

        return fileNameList;
    }

    @Override
    public TestResult testConnection() throws IOException {

        boolean result = s3Client.doesBucketExist(bucketName);
        if (result) {
            return new TestResult("OK.", TestResult.TestCode.ACCESIBLE);
        }
        return new TestResult("Storage bucket does not exists or it is not accessible!",
                TestResult.TestCode.INACCESSIBLE);
    }

}