com.bennavetta.appsite.webapi.ContentController.java Source code

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Here is the source code for com.bennavetta.appsite.webapi.ContentController.java

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/**
 * Copyright 2013 Ben Navetta <ben@bennavetta.com>
 *
 * 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 com.bennavetta.appsite.webapi;

import java.io.IOException;
import java.io.InputStream;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.security.MessageDigest;
import java.util.ArrayList;
import java.util.List;

import javax.annotation.Nullable;
import javax.servlet.http.HttpServletRequest;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.HttpStatus;
import org.springframework.stereotype.Controller;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.servlet.HandlerMapping;

import com.bennavetta.appsite.file.Resource;
import com.bennavetta.appsite.file.ResourceService;
import com.google.common.base.Predicate;
import com.google.common.collect.Iterables;
import com.google.common.net.MediaType;

@Controller
@RequestMapping(value = "/content")
public class ContentController {
    private Logger log = LoggerFactory.getLogger(getClass());

    @Autowired
    private ResourceService resources;

    @RequestMapping(value = "/upload/**", method = RequestMethod.POST)
    @ResponseStatus(HttpStatus.CREATED)
    public void uploadFile(HttpServletRequest request) throws IOException {
        MediaType type = MediaType.parse(request.getContentType());
        String path = extractPathFromPattern(request);
        log.trace("Uploading resource {} with type {}", path, type);

        Resource old = Resource.get(path);
        if (old != null) {
            log.trace("Deleting prior resource: {}", old);
            old.delete();
        }

        try (InputStream in = request.getInputStream()) {
            ReadableByteChannel channel = Channels.newChannel(in);
            resources.create(path, type, channel);
        }
    }

    /**
     * Delete the list of files specified by the response body (a JSON array) and return a list of
     * all files that were successfully deleted.
     * @param paths
     * @return
     * @throws ResourceNotFoundException if any of the resources are not found
     */
    @RequestMapping(value = "/delete/**", method = RequestMethod.DELETE)
    @ResponseBody
    public String deleteFiles(HttpServletRequest request) throws ResourceNotFoundException {
        String path = extractPathFromPattern(request);
        Resource resource = Resource.get(path);
        if (resource != null) {
            log.trace("Deleting resource {}", resource);
            resource.delete();
            return resource.getPath();
        } else {
            throw new ResourceNotFoundException(path);
        }
    }

    /**
     * Given a list of files and their MD5 hashes, calculate which ones are the same on the server, which ones should be uploaded,
     * and which ones should be deleted on the server (via a delete request).
     * @param files
     * @return
     */
    @RequestMapping(value = "/diff", method = RequestMethod.POST)
    @ResponseBody
    public DiffResponse calculateDiff(@RequestBody List<DiffFile> files) {
        List<String> same = new ArrayList<>();
        List<String> different = new ArrayList<>();
        List<String> extra = new ArrayList<>();

        for (DiffFile file : files) {
            Resource onServer = Resource.get(file.getPath());
            if (onServer == null) {
                different.add(file.getPath());
                continue;
            }
            if (MessageDigest.isEqual(file.getMd5(), onServer.getMD5())) {
                same.add(file.getPath());
            } else {
                different.add(file.getPath());
            }
        }

        //TODO: find a better way of doing this?
        for (String path : Resource.allResources()) {
            if (!Iterables.all(files, new PathMatches(path))) //add the path to extras if none of the files match it
            {
                extra.add(path);
            }
        }

        DiffResponse response = new DiffResponse();
        response.setDifferent(different);
        response.setExtra(extra);
        response.setSame(same);
        return response;
    }

    private static class PathMatches implements Predicate<DiffFile> {
        private String path;

        public PathMatches(String path) {
            this.path = path;
        }

        @Override
        public boolean apply(@Nullable DiffFile input) {
            return path.equals(input.getPath());
        }
    }

    /**
     * Given a request that was matched against a @RequestMapping method, extract a trailing path from it.
     * For example, given a mapping of '/foo/**' and a request of '/foo/bar/baz', this would return 'bar/baz'.
     * @param request the matched request
     * @return the final path component
     * @see http://stackoverflow.com/questions/3686808/spring-3-requestmapping-get-path-value
     */
    public static String extractPathFromPattern(HttpServletRequest request) {
        String path = (String) request.getAttribute(HandlerMapping.PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE);
        String bestMatchPattern = (String) request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE);

        AntPathMatcher apm = new AntPathMatcher();
        String finalPath = apm.extractPathWithinPattern(bestMatchPattern, path);

        return finalPath;
    }
}