001/*
002 * (C) Copyright 2015 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *     http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 *
016 * Contributors:
017 *     Nuxeo
018 */
019
020package org.nuxeo.ecm.blob.azure;
021
022import java.io.File;
023import java.io.FileInputStream;
024import java.io.FileOutputStream;
025import java.io.IOException;
026import java.io.InputStream;
027import java.io.OutputStream;
028import java.net.URISyntaxException;
029
030import org.apache.commons.codec.binary.Hex;
031import org.apache.commons.logging.Log;
032import org.apache.commons.logging.LogFactory;
033import org.nuxeo.ecm.core.blob.binary.FileStorage;
034
035import com.microsoft.azure.storage.StorageErrorCode;
036import com.microsoft.azure.storage.StorageException;
037import com.microsoft.azure.storage.blob.CloudBlobContainer;
038import com.microsoft.azure.storage.blob.CloudBlockBlob;
039import com.microsoft.azure.storage.core.Base64;
040
041/**
042 * @author <a href="mailto:[email protected]">Arnaud Kervern</a>
043 * @since 7.10
044 */
045public class AzureFileStorage implements FileStorage {
046
047    private static final Log log = LogFactory.getLog(AzureFileStorage.class);
048
049    protected CloudBlobContainer container;
050
051    protected String prefix;
052
053    public AzureFileStorage(CloudBlobContainer container, String prefix) {
054        this.container = container;
055        this.prefix = prefix;
056    }
057
058    @Override
059    public void storeFile(String digest, File file) throws IOException {
060        long t0 = 0;
061        if (log.isDebugEnabled()) {
062            t0 = System.currentTimeMillis();
063            log.debug("storing blob " + digest + " to Azure");
064        }
065        CloudBlockBlob blob;
066        try {
067            blob = container.getBlockBlobReference(prefix + digest);
068            if (blob.exists()) {
069                if (isBlobDigestCorrect(digest, blob)) {
070                    if (log.isDebugEnabled()) {
071                        log.debug("blob " + digest + " is already in Azure");
072                    }
073                    return;
074                }
075            }
076
077            try (InputStream is = new FileInputStream(file)) {
078                blob.upload(is, file.length());
079            }
080        } catch (StorageException | URISyntaxException e) {
081            throw new IOException(e);
082        } finally {
083            if (log.isDebugEnabled()) {
084                long dtms = System.currentTimeMillis() - t0;
085                log.debug("stored blob " + digest + " to Azure in " + dtms + "ms");
086            }
087        }
088    }
089
090    @Override
091    public boolean fetchFile(String digest, File file) throws IOException {
092        long t0 = 0;
093        if (log.isDebugEnabled()) {
094            t0 = System.currentTimeMillis();
095            log.debug("fetching blob " + digest + " from Azure");
096        }
097        try {
098            CloudBlockBlob blob = container.getBlockBlobReference(prefix + digest);
099            if (!(blob.exists() && isBlobDigestCorrect(digest, blob))) {
100                log.error("Invalid ETag in Azure, AzDigest=" + blob.getProperties().getContentMD5() + " digest="
101                        + digest);
102                return false;
103            }
104            try (OutputStream os = new FileOutputStream(file)) {
105                blob.download(os);
106            }
107            return true;
108        } catch (URISyntaxException e) {
109            throw new IOException(e);
110        } catch (StorageException e) {
111            return false;
112        } finally {
113            if (log.isDebugEnabled()) {
114                long dtms = System.currentTimeMillis() - t0;
115                log.debug("fetched blob " + digest + " from Azure in " + dtms + "ms");
116            }
117        }
118    }
119
120    protected static boolean isMissingKey(StorageException e) {
121        return e.getErrorCode().equals(StorageErrorCode.RESOURCE_NOT_FOUND.toString());
122    }
123
124    protected static boolean isBlobDigestCorrect(String digest, CloudBlockBlob blob) {
125        return isBlobDigestCorrect(digest, blob.getProperties().getContentMD5());
126    }
127
128    protected static boolean isBlobDigestCorrect(String digest, String contentMD5) {
129        return digest.equals(decodeContentMD5(contentMD5));
130    }
131
132    protected static String decodeContentMD5(String contentMD5) {
133        try {
134            byte[] bytes = Base64.decode(contentMD5);
135            return Hex.encodeHexString(bytes);
136        } catch (IllegalArgumentException e) {
137            return null;
138        }
139    }
140}