ContentUriAccessPlugin.java

/**
 * Copyright (c) Codice Foundation
 * <p/>
 * This is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser
 * General Public License as published by the Free Software Foundation, either version 3 of the
 * License, or any later version.
 * <p/>
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
 * even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details. A copy of the GNU Lesser General Public License
 * is distributed along with this program and can be found at
 * <http://www.gnu.org/licenses/lgpl.html>.
 */
package org.codice.ddf.catalog.content.plugin.uri;

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

import ddf.catalog.content.data.ContentItem;
import ddf.catalog.data.Metacard;
import ddf.catalog.operation.CreateRequest;
import ddf.catalog.operation.DeleteRequest;
import ddf.catalog.operation.DeleteResponse;
import ddf.catalog.operation.QueryRequest;
import ddf.catalog.operation.QueryResponse;
import ddf.catalog.operation.ResourceRequest;
import ddf.catalog.operation.ResourceResponse;
import ddf.catalog.operation.UpdateRequest;
import ddf.catalog.plugin.AccessPlugin;
import ddf.catalog.plugin.StopProcessingException;

/**
 * The {@code ContentUriAccessPlugin} prevents a {@link Metacard}s {@link Metacard#RESOURCE_URI} with a scheme of
 * {@link ContentItem#CONTENT_SCHEME} from being overridden by an incoming {@link UpdateRequest}.
 */
public class ContentUriAccessPlugin implements AccessPlugin {

    private static final String CANNOT_OVERWRITE_MESSAGE =
            "Cannot overwrite resource URI in content store.";

    @Override
    public CreateRequest processPreCreate(CreateRequest input) throws StopProcessingException {
        return input;
    }

    @Override
    public UpdateRequest processPreUpdate(UpdateRequest input,
            Map<String, Metacard> existingMetacards) throws StopProcessingException {
        for (Map.Entry<Serializable, Metacard> entry : input.getUpdates()) {
            Metacard existingMetacard = existingMetacards.get(entry.getKey()
                    .toString());

            if (existingMetacard.getResourceURI() != null && !ContentItem.CONTENT_SCHEME.equals(
                    existingMetacard.getResourceURI()
                            .getScheme())) {
                continue;
            }

            if (oneOrOtherUriNull(existingMetacard, entry.getValue())) {
                throw new StopProcessingException(CANNOT_OVERWRITE_MESSAGE);
            }

            if (entry.getValue()
                    .getResourceURI() != null && !existingMetacard.getResourceURI()
                    .equals(entry.getValue()
                            .getResourceURI())) {
                throw new StopProcessingException(CANNOT_OVERWRITE_MESSAGE);
            }
        }
        return input;
    }

    private boolean oneOrOtherUriNull(Metacard existingMetacard, Metacard updatedMetacard) {
        return (existingMetacard.getResourceURI() == null
                && updatedMetacard.getResourceURI() != null) || (
                existingMetacard.getResourceURI() != null
                        && updatedMetacard.getResourceURI() == null);
    }

    @Override
    public DeleteRequest processPreDelete(DeleteRequest input) throws StopProcessingException {
        return input;
    }

    @Override
    public DeleteResponse processPostDelete(DeleteResponse input) throws StopProcessingException {
        return input;
    }

    @Override
    public QueryRequest processPreQuery(QueryRequest input) throws StopProcessingException {
        return input;
    }

    @Override
    public QueryResponse processPostQuery(QueryResponse input) throws StopProcessingException {
        return input;
    }

    @Override
    public ResourceRequest processPreResource(ResourceRequest input)
            throws StopProcessingException {
        return input;
    }

    @Override
    public ResourceResponse processPostResource(ResourceResponse input, Metacard metacard)
            throws StopProcessingException {
        return input;
    }
}