com.google.appinventor.server.WebAppLaunchServlet.java Source code

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Here is the source code for com.google.appinventor.server.WebAppLaunchServlet.java

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// -*- mode: java; c-basic-offset: 2; -*-
// Copyright 2009-2011 Google, All Rights reserved
// Copyright 2011-2012 MIT, All rights reserved
// Released under the Apache License, Version 2.0
// http://www.apache.org/licenses/LICENSE-2.0

package com.google.appinventor.server;

import com.google.appinventor.server.storage.StorageIo;
import com.google.appinventor.server.storage.StorageIoInstanceHolder;
import com.google.appinventor.server.util.CacheHeaders;
import com.google.appinventor.server.util.CacheHeadersImpl;
import com.google.appinventor.shared.rpc.ServerLayout;
import com.google.appinventor.shared.rpc.UploadResponse;

import com.google.appinventor.shared.storage.StorageUtil;
import org.apache.commons.fileupload.FileItemStream;
import org.apache.commons.fileupload.FileItemIterator;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

import java.io.*;
import java.util.logging.Logger;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet for uploading and downloading files for the Live Web App
 */
public class WebAppLaunchServlet extends OdeServlet {
    /*
     * URIs for launch request are structured as follows:
     *    /<baseurl>/webapp_launch/webapp/<filePath>
     */

    // Constants for accessing split URI
    /*
     * Upload kind is: "file".
     * Constants for this is defined in ServerLayout.
     */
    private static final int REQUEST_INDEX = 3;
    // Since the file path may contain slashes, it must be the last component in the URI.
    private static final int FILE_PATH_INDEX = 4;
    private static final int SPLIT_LIMIT_FILE = 5;

    // Logging support
    private static final Logger LOG = Logger.getLogger(WebAppLaunchServlet.class.getName());

    //storage
    private final StorageIo storageIo = StorageIoInstanceHolder.INSTANCE;

    @Override
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {

        String userId = userInfoProvider.getUserId();
        String launchFile;

        try {
            String uri = req.getRequestURI();
            // First, call split with no limit parameter.
            String[] uriComponents = uri.split("/");
            String launchKind = uriComponents[REQUEST_INDEX];

            if (launchKind.equals(ServerLayout.WEBAPP_FILE)) {
                uriComponents = uri.split("/", SPLIT_LIMIT_FILE);
                if (FILE_PATH_INDEX > uriComponents.length) {
                    throw CrashReport.createAndLogError(LOG, req, null,
                            new IllegalArgumentException("Missing web app file path."));
                }
                String fileName = uriComponents[FILE_PATH_INDEX];
                launchFile = storageIo.downloadUserFile(userId, fileName, "UTF-8");

            } else {
                throw CrashReport.createAndLogError(LOG, req, null,
                        new IllegalArgumentException("Unknown launch kind: " + launchKind));
            }

        } catch (IllegalArgumentException e) {
            throw CrashReport.createAndLogError(LOG, req, null, e);
        }

        byte[] content = launchFile.getBytes();
        // Set http response information
        resp.setStatus(HttpServletResponse.SC_OK);
        resp.setContentType("text/html");
        resp.setContentLength(launchFile.length());

        // Attach download data
        ServletOutputStream out = resp.getOutputStream();
        out.write(content);
        out.close();
    }
}