AssetApiController.java

/*
 * Copyright 2015-2016 EuregJUG.
 *
 * 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.
 */
package eu.euregjug.site.assets;

import com.mongodb.gridfs.GridFSDBFile;
import java.io.IOException;
import java.io.InputStream;
import java.util.Optional;
import java.util.concurrent.TimeUnit;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.tika.Tika;
import org.apache.tika.io.TikaInputStream;
import org.apache.tika.mime.MediaType;
import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.gridfs.GridFsTemplate;
import org.springframework.security.access.prepost.PreAuthorize;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

import static java.time.format.DateTimeFormatter.RFC_1123_DATE_TIME;
import static org.springframework.web.bind.annotation.RequestMethod.POST;
import static java.time.ZoneId.of;
import static java.time.ZonedDateTime.now;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import static org.springframework.http.HttpStatus.CREATED;
import org.springframework.web.bind.annotation.ResponseStatus;

/**
 * @author Michael J. Simons, 2015-12-29
 */
@Controller
@RequestMapping("/api/assets")
@RequiredArgsConstructor
@Slf4j
class AssetApiController {

    private final Tika tika = new Tika();

    private final GridFsTemplate gridFs;

    @RequestMapping(method = POST)
    @PreAuthorize("isAuthenticated()")
    @ResponseBody
    @ResponseStatus(CREATED)
    public String create(
            @RequestParam("assetData") final MultipartFile assetData
    ) throws IOException {

        // Check duplicates
        final GridFSDBFile file = this.gridFs.findOne(Query.query(Criteria.where("filename").is(assetData.getOriginalFilename())));
        if (file != null) {
            throw new DataIntegrityViolationException(String.format("Asset with name '%s' already exists", assetData.getOriginalFilename()));
        } else {
            try (InputStream usedStream = TikaInputStream.get(assetData.getInputStream())) {
                MediaType mediaType = null;
                try {
                    mediaType = MediaType.parse(tika.detect(usedStream, assetData.getOriginalFilename()));
                } catch (IOException e) {
                    log.warn("Could not detect content type", e);
                }
                this.gridFs.store(assetData.getInputStream(), assetData.getOriginalFilename(), Optional.ofNullable(mediaType).map(MediaType::toString).orElse(null));
                return assetData.getOriginalFilename();
            }
        }
    }

    @RequestMapping({"/{filename:.+}"})
    public void get(
            @PathVariable final String filename,
            final HttpServletRequest request,
            final HttpServletResponse response
    ) throws IOException {
        final GridFSDBFile file = this.gridFs.findOne(Query.query(Criteria.where("filename").is(filename)));
        if (file == null) {
            response.setStatus(HttpServletResponse.SC_NOT_FOUND);
        } else {
            final int cacheForDays = 365;
            response.setHeader("Content-Type", file.getContentType());
            response.setHeader("Content-Disposition", String.format("inline; filename=\"%s\"", file.getFilename()));
            response.setHeader("Expires", now(of("UTC")).plusDays(cacheForDays).format(RFC_1123_DATE_TIME));
            response.setHeader("Cache-Control", String.format("max-age=%d, %s", TimeUnit.DAYS.toSeconds(cacheForDays), "public"));
            file.writeTo(response.getOutputStream());
            response.flushBuffer();
        }
    }
}