AnyToThumbnailConverter.java

/*
 * (C) Copyright 2013 Nuxeo SA (http://nuxeo.com/) and others.
 *
 * 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.
 *
 * Contributors:
 *     Thomas Roger
 */

package org.nuxeo.ecm.platform.thumbnail.converter;

import static org.nuxeo.ecm.platform.thumbnail.ThumbnailConstants.ANY_TO_PDF_TO_THUMBNAIL_CONVERTER_NAME;
import static org.nuxeo.ecm.platform.thumbnail.ThumbnailConstants.PDF_AND_IMAGE_TO_THUMBNAIL_CONVERTER_NAME;

import java.io.Serializable;
import java.util.Map;
import java.util.regex.Pattern;

import org.nuxeo.ecm.core.api.Blob;
import org.nuxeo.ecm.core.api.blobholder.BlobHolder;
import org.nuxeo.ecm.core.convert.api.ConversionException;
import org.nuxeo.ecm.core.convert.api.ConversionService;
import org.nuxeo.ecm.core.convert.extension.Converter;
import org.nuxeo.ecm.core.convert.extension.ConverterDescriptor;
import org.nuxeo.runtime.api.Framework;

/**
 * Base converter choosing the correct convert to generate a thumbnail according to the Blob's mime type.
 *
 * @since 5.8
 */
public class AnyToThumbnailConverter implements Converter {

    public static final String PDF_MIME_TYPE = "application/pdf";

    public static final Pattern PDF_MIME_TYPE_PATTERN = Pattern.compile("application/.*pdf");

    public static final String ANY_TO_PDF_CONVERTER_NAME = "any2pdf";

    @Override
    public void init(ConverterDescriptor descriptor) {
    }

    @Override
    public BlobHolder convert(BlobHolder blobHolder, Map<String, Serializable> parameters) throws ConversionException {
        Blob sourceBlob;
        sourceBlob = blobHolder.getBlob();
        if (sourceBlob == null) {
            return null;
        }

        String mimeType = sourceBlob.getMimeType();
        if (mimeType == null) {
            return null;
        }

        ConversionService conversionService = Framework.getLocalService(ConversionService.class);

        String converterName = null;
        if ((mimeType.startsWith("image/") || PDF_MIME_TYPE_PATTERN.matcher(mimeType).matches())
                && conversionService.isConverterAvailable(PDF_AND_IMAGE_TO_THUMBNAIL_CONVERTER_NAME, true).isAvailable()) {
            converterName = PDF_AND_IMAGE_TO_THUMBNAIL_CONVERTER_NAME;
        } else if (conversionService.isSourceMimeTypeSupported(ANY_TO_PDF_CONVERTER_NAME, mimeType)
                && conversionService.isConverterAvailable(ANY_TO_PDF_CONVERTER_NAME, true).isAvailable()) {
            converterName = ANY_TO_PDF_TO_THUMBNAIL_CONVERTER_NAME;
        }
        return converterName == null ? null : conversionService.convert(converterName, blobHolder, parameters);
    }
}