org.odk.aggregate.servlet.FormUploadServlet.java Source code

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Here is the source code for org.odk.aggregate.servlet.FormUploadServlet.java

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/*
 * Copyright (C) 2009 Google Inc.
 * 
 * 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 org.odk.aggregate.servlet;

import java.io.IOException;
import java.io.PrintWriter;

import javax.persistence.EntityManager;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.odk.aggregate.EMFactory;
import org.odk.aggregate.constants.ErrorConsts;
import org.odk.aggregate.constants.HtmlConsts;
import org.odk.aggregate.constants.HtmlUtil;
import org.odk.aggregate.constants.ServletConsts;
import org.odk.aggregate.exception.ODKFormAlreadyExistsException;
import org.odk.aggregate.form.Form;
import org.odk.aggregate.parser.FormParserForJavaRosa;
import org.odk.aggregate.parser.MultiPartFormData;
import org.odk.aggregate.parser.MultiPartFormItem;

import com.google.appengine.api.users.User;
import com.google.appengine.api.users.UserService;
import com.google.appengine.api.users.UserServiceFactory;

/**
 * Servlet to upload, parse, and save an XForm
 *
 * @author wbrunette@gmail.com
 *
 */
public class FormUploadServlet extends ServletUtilBase {

    /**
     * Serial number for serialization
     */
    private static final long serialVersionUID = -3784460108221008112L;

    /**
     * URI from base
     */
    public static final String ADDR = "upload";

    /**
     * Title for generated webpage
     */
    private static final String TITLE_INFO = "Xform Upload";

    /**
     * Handler for HTTP Get request to create xform upload page
     * 
     * @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest,
     *      javax.servlet.http.HttpServletResponse)
     */
    @Override
    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {

        // verify user is logged in
        if (!verifyCredentials(req, resp)) {
            return;
        }

        beginBasicHtmlResponse(TITLE_INFO, resp, req, true); // header info

        PrintWriter out = resp.getWriter();
        out.write(HtmlUtil.createFormBeginTag(ADDR, ServletConsts.MULTIPART_FORM_DATA, ServletConsts.POST));
        out.write("Name of Xform:" + HtmlConsts.LINE_BREAK);
        out.write(HtmlUtil.createInput(HtmlConsts.INPUT_TYPE_TEXT, ServletConsts.FORM_NAME_PRAM, null));
        out.write(HtmlConsts.LINE_BREAK + HtmlConsts.LINE_BREAK);
        out.write("Location of Xform definition to be uploaded:" + HtmlConsts.LINE_BREAK);
        out.write(HtmlUtil.createInput(HtmlConsts.INPUT_TYPE_FILE, ServletConsts.FORM_DEF_PRAM, null));
        out.write(HtmlConsts.LINE_BREAK + HtmlConsts.LINE_BREAK);
        out.write(HtmlUtil.createInput(HtmlConsts.INPUT_TYPE_SUBMIT, null, "Upload"));
        out.write(HtmlConsts.FORM_CLOSE);
        finishBasicHtmlResponse(resp);
    }

    /**
     * Handler for HTTP Post request that takes an xform, parses, and saves a 
     * parsed version in the datastore 
     * 
     * @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest,
     *      javax.servlet.http.HttpServletResponse)
     */
    @Override
    public void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
        UserService userService = UserServiceFactory.getUserService();
        User user = userService.getCurrentUser();

        // verify user is logged in
        if (!verifyCredentials(req, resp)) {
            return;
        }

        // verify request is multipart
        if (!ServletFileUpload.isMultipartContent(req)) {
            resp.sendError(HttpServletResponse.SC_BAD_REQUEST, ErrorConsts.NO_MULTI_PART_CONTENT);
            return;
        }

        try {
            // process form
            MultiPartFormData uploadedFormItems = new MultiPartFormData(req);

            MultiPartFormItem formNameData = uploadedFormItems.getFormDataByFieldName(ServletConsts.FORM_NAME_PRAM);
            MultiPartFormItem formXmlData = uploadedFormItems.getFormDataByFieldName(ServletConsts.FORM_DEF_PRAM);

            FormParserForJavaRosa parser = null;
            String formName = null;
            String formXml = null;
            String xmlFileName = "default.xml";

            if (formNameData != null) {
                formName = formNameData.getStream().toString("UTF-8");
            }
            if (formXmlData != null) {
                // TODO: changed added output stream writer. probably something better exists
                formXml = formXmlData.getStream().toString("UTF-8");
                xmlFileName = formXmlData.getFilename();
            }

            // persist form
            EntityManager em = EMFactory.get().createEntityManager();

            if (formName != null && formXml != null) {
                try {
                    parser = new FormParserForJavaRosa(formName, user.getNickname(), formXml, xmlFileName, em);
                } catch (ODKFormAlreadyExistsException e) {
                    resp.sendError(HttpServletResponse.SC_CONFLICT, ErrorConsts.FORM_WITH_ODKID_EXISTS);
                    return;
                }
            } else {
                resp.sendError(HttpServletResponse.SC_BAD_REQUEST, ErrorConsts.MISSING_FORM_INFO);
                return;
            }

            // TODO: do better error handling
            try {
                Form form = parser.getForm();
                em.persist(form);
                form.printDataTree(System.out);
            } catch (Exception e) {
                e.printStackTrace();
            }
            em.close();
            resp.sendRedirect(FormsServlet.ADDR);

        } catch (FileUploadException e) {
            e.printStackTrace(resp.getWriter());
        }

    }
}