cz.cvut.portal.kos.services.RestKOSapiService.java Source code

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Here is the source code for cz.cvut.portal.kos.services.RestKOSapiService.java

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/*
 * The MIT License
 *
 * Copyright 2013 Jakub Jirutka <jakub@jirutka.cz>.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package cz.cvut.portal.kos.services;

import cz.cvut.portal.kos.model.Course;
import cz.cvut.portal.kos.services.support.ListPaginator;
import cz.cvut.portal.kos.services.support.Paginator;
import cz.cvut.portal.kos.services.support.ListPaginator.DataFetcher;
import cz.cvut.portal.kos.utils.UriBuilder;
import cz.jirutka.atom.jaxb.Entry;
import cz.jirutka.atom.jaxb.Feed;
import java.net.URI;
import java.util.List;
import org.apache.commons.lang.StringUtils;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.client.RestOperations;
import org.springframework.web.client.RestTemplate;

/**
 *
 * @author Jakub Jirutka <jakub@jirutka.cz>
 */
public class RestKOSapiService implements KOSapiService {

    private static final String PARAM_LIMIT = "limit";
    private static final String PARAM_OFFSET = "offset";
    private static final char[] ILLEGAL_CHARS = { '\'', '"', '&', '?' };

    private RestOperations rest;

    // will be set from properties file
    private @Value("${kosapi.uri.base}") String baseUri;
    private @Value("${kosapi.uri.courses.query-simple}") String coursesQuerySimpleUri;
    private @Value("${kosapi.uri.courses.query-rsql}") String coursesQueryRsqlUri;
    private @Value("${kosapi.uri.courses.get}") String coursesGetUri;

    public Paginator<Course> findCoursesByCodeOrName(final String codeOrName) {
        validateArgument(codeOrName);

        return new ListPaginator<>(new DataFetcher<Course>() {
            public List<Course> fetchPage(int itemsPerPage, int startIndex) {
                URI url = path(coursesQuerySimpleUri).expand("query", codeOrName)
                        .queryParam(PARAM_LIMIT, itemsPerPage).queryParam(PARAM_OFFSET, startIndex).build();

                // pass as String to perform encoding
                return rest.getForObject(url.toString(), Feed.class).getContents();
            }
        });
    }

    public Course getCourse(String code, int detailLevel) {
        validateArgument(code);

        URI url = path(coursesGetUri).expand("code", code).queryParam("detail", detailLevel).build();

        // pass as String to perform encoding
        Entry<Course> entry = rest.getForObject(url.toString(), Entry.class);
        return entry.getContent();
    }

    private UriBuilder path(String path) {
        return UriBuilder.fromBase(baseUri).path(path);
    }

    private void validateArgument(String str) {
        if (StringUtils.isBlank(str)) {
            throw new IllegalArgumentException("Argument is blank");
        }
        if (StringUtils.containsAny(str, ILLEGAL_CHARS)) {
            throw new IllegalArgumentException("Argument contains illegal characters");
        }
    }

    ////////  Accessors  ////////

    public void setRestTemplate(RestTemplate restTemplate) {
        this.rest = restTemplate;
    }

}