001/*
002 * Copyright (c) 2006-2011 Nuxeo SA (http://nuxeo.com/) and others.
003 *
004 * All rights reserved. This program and the accompanying materials
005 * are made available under the terms of the Eclipse Public License v1.0
006 * which accompanies this distribution, and is available at
007 * http://www.eclipse.org/legal/epl-v10.html
008 *
009 * Contributors:
010 *     Anahide Tchertchian
011 */
012package org.nuxeo.ecm.core.api.externalblob;
013
014import java.io.IOException;
015import java.io.Serializable;
016import java.util.Map;
017
018import org.nuxeo.ecm.core.api.Blob;
019import org.nuxeo.ecm.core.api.PropertyException;
020
021/**
022 * Interface to implement when defining a way to get a {@link Blob} that is not stored at the usual place handled by the
023 * repository.
024 * <p>
025 * This is done storing a string instead of a blob, using a prefix that makes it possible to find the adapter in charge
026 * of retrieving the file. It makes it also possible to use the same adapter implementation for different
027 * configurations, in conjunction with properties.
028 * <p>
029 * The string will look something like "fs:file/foo.odt", "fs" being the prefix, and "file/foo.odt" being the local
030 * name, with all the needed information to retrieve the actual file for this adapter.
031 *
032 * @author Anahide Tchertchian
033 */
034public interface ExternalBlobAdapter extends Serializable {
035
036    String PREFIX_SEPARATOR = ":";
037
038    /**
039     * Returns the prefix to use as marker for this adapter
040     */
041    String getPrefix();
042
043    /**
044     * Sets the prefix to use as marker for this adapter
045     */
046    void setPrefix(String prefix);
047
048    /**
049     * Return specific properties for this adapter. Can be used for whatever useful property.
050     */
051    Map<String, String> getProperties();
052
053    /**
054     * Return property with gievn name.
055     * <p>
056     * Returns null if no property value is found.
057     */
058    String getProperty(String name);
059
060    /**
061     * Set specific properties for this adapter. Can be used for whatever useful property.
062     */
063    void setProperties(Map<String, String> properties);
064
065    /**
066     * Retrieves the blob for given uri.
067     *
068     * @param uri the uri describing what adapter handles the file and the needed info to retrieve it.
069     * @return the resolved blob.
070     * @throws PropertyException if the blob cannot be retrieved (if adapter cannot retrieve it or if file is not found
071     *             for instance)
072     */
073    Blob getBlob(String uri) throws PropertyException, IOException;
074
075}