com.qcloud.cos.internal.crypto.MultipartUploadCryptoContext Maven / Gradle / Ivy

/*
 * Copyright 2010-2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 *  http://aws.amazon.com/apache2.0
 *
 * or in the "license" file accompanying this file. This file 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.
 
 * According to cos feature, we modify some class，comment, field name, etc.
 */


package com.qcloud.cos.internal.crypto;

import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

import com.qcloud.cos.annotation.GuardedBy;
import com.qcloud.cos.exception.CosClientException;

/**
 * Contextual information for an in-flight multipart upload.
 */
public class MultipartUploadCryptoContext {
    private final String bucketName;
    private final String key;
    private boolean hasFinalPartBeenSeen;
    /**
     * the materialDescription is an optional attribute that is only non-null when the material
     * description is set on a per request basis
     */
    private Map materialsDescription;

    private final ContentCryptoMaterial cekMaterial;
    /**
     * Can be used to enforce serial uploads.
     */
    @GuardedBy("this")
    private int partNumber;
    /**
     * True if a multi-part upload is currently in progress; false otherwise.
     */
    private volatile boolean partUploadInProgress;

    protected MultipartUploadCryptoContext(String bucketName, String key,
            ContentCryptoMaterial cekMaterial) {
        this.bucketName = bucketName;
        this.key = key;
        this.cekMaterial = cekMaterial;
    }

    public final String getBucketName() {
        return bucketName;
    }

    public final String getKey() {
        return key;
    }

    public final boolean hasFinalPartBeenSeen() {
        return hasFinalPartBeenSeen;
    }

    public final void setHasFinalPartBeenSeen(boolean hasFinalPartBeenSeen) {
        this.hasFinalPartBeenSeen = hasFinalPartBeenSeen;
    }

    /**
     * @return the materialsDescription
     */
    public final Map getMaterialsDescription() {
        return materialsDescription;
    }

    /**
     * @param materialsDescription the materialsDescription to set
     */
    public final void setMaterialsDescription(Map materialsDescription) {
        this.materialsDescription = materialsDescription == null ? null
                : Collections.unmodifiableMap(new HashMap(materialsDescription));
    }

    /**
     * Convenient method to return the content encrypting cipher lite (which is stateful) for the
     * multi-part uploads.
     */
    CipherLite getCipherLite() {
        return cekMaterial.getCipherLite();
    }

    /**
     * Returns the content encrypting cryptographic material for the multi-part uploads.
     */
    ContentCryptoMaterial getContentCryptoMaterial() {
        return cekMaterial;
    }

    /**
     * Can be used to check the next part number must either be the same (if it was an retry) or
     * increment by exactly 1 during a serial part uploads.
     * 
     * As a side effect, the {@link #partUploadInProgress} will be set to true upon successful
     * completion of this method. Caller of this method is responsible to call
     * {@link #endPartUpload()} in a finally block once the respective part-upload is completed
     * (either normally or abruptly).
     * 
     * @see #endPartUpload()
     * 
     * @throws SdkClientException if parallel part upload is detected
     */
    void beginPartUpload(final int nextPartNumber) throws CosClientException {
        if (nextPartNumber < 1)
            throw new IllegalArgumentException("part number must be at least 1");
        if (partUploadInProgress) {
            throw new CosClientException("Parts are required to be uploaded in series");
        }
        synchronized (this) {
            if (partUploadInProgress) {
                throw new CosClientException("Parts are required to be uploaded in series");
            }
            if (nextPartNumber - partNumber <= 1) {
                partNumber = nextPartNumber;
                partUploadInProgress = true;
            } else {
                throw new CosClientException(
                        "Parts are required to be uploaded in series (partNumber=" + partNumber
                                + ", nextPartNumber=" + nextPartNumber + ")");
            }
        }
    }

    /**
     * Used to mark the completion of a part upload before the next. Should be invoked in a finally
     * block, and must be preceded previously by a call to {@link #beginPartUpload(int)}.
     * 
     * @see #beginPartUpload(int)
     */
    void endPartUpload() {
        partUploadInProgress = false;
    }
}