document-server-integration/web/documentserver-example/nodejs/helpers/documentService.js

/*
 *
 * (c) Copyright Ascensio System Limited 2010-2017
 *
 * This program is freeware. You can redistribute it and/or modify it under the terms of the GNU 
 * General Public License (GPL) version 3 as published by the Free Software Foundation (https://www.gnu.org/copyleft/gpl.html). 
 * In accordance with Section 7(a) of the GNU GPL its Section 15 shall be amended to the effect that 
 * Ascensio System SIA expressly excludes the warranty of non-infringement of any third-party rights.
 *
 * THIS PROGRAM IS DISTRIBUTED WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY OR
 * FITNESS FOR A PARTICULAR PURPOSE. For more details, see GNU GPL at https://www.gnu.org/copyleft/gpl.html
 *
 * You can contact Ascensio System SIA by email at sales@onlyoffice.com
 *
 * The interactive user interfaces in modified source and object code versions of ONLYOFFICE must display 
 * Appropriate Legal Notices, as required under Section 5 of the GNU GPL version 3.
 *
 * Pursuant to Section 7 § 3(b) of the GNU GPL you must retain the original ONLYOFFICE logo which contains 
 * relevant author attributions when distributing the software. If the display of the logo in its graphic 
 * form is not reasonably feasible for technical reasons, you must include the words "Powered by ONLYOFFICE" 
 * in every copy of the program you distribute. 
 * Pursuant to Section 7 § 3(e) we decline to grant you any rights under trademark law for use of our trademarks.
 *
*/

var path = require("path");
var urlModule = require("url");
var urllib = require("urllib");
var xml2js = require("xml2js");
var jwt = require("jsonwebtoken");
var jwa = require("jwa");
var fileUtility = require("./fileUtility");
var guidManager = require("./guidManager");
var configServer = require('config').get('server');
var siteUrl = configServer.get('siteUrl');
var cfgSignatureEnable = configServer.get('token.enable');
var cfgSignatureUseForRequest = configServer.get('token.useforrequest');
var cfgSignatureAuthorizationHeader = configServer.get('token.authorizationHeader');
var cfgSignatureAuthorizationHeaderPrefix = configServer.get('token.authorizationHeaderPrefix');
var cfgSignatureSecretExpiresIn = configServer.get('token.expiresIn');
var cfgSignatureSecret = configServer.get('token.secret');
var cfgSignatureSecretAlgorithmRequest = configServer.get('token.algorithmRequest');

var documentService = {};

documentService.userIp = null;

documentService.getConvertedUriSync = function (documentUri, fromExtension, toExtension, documentRevisionId, callback) {
    documentRevisionId = documentService.generateRevisionId(documentRevisionId || documentUri);

    documentService.getConvertedUri(documentUri, fromExtension, toExtension, documentRevisionId, false, function (err, data) {
        if (err) {
            callback();
            return;
        }
        var res = documentService.getResponseUri(data);
        callback(res.value);
    });
};

documentService.getConvertedUri = function (documentUri, fromExtension, toExtension, documentRevisionId, async, callback) {
    fromExtension = fromExtension || fileUtility.getFileExtension(documentUri);

    var title = fileUtility.getFileName(documentUri) || guidManager.newGuid();

    documentRevisionId = documentService.generateRevisionId(documentRevisionId || documentUri);

    var params = {
        async: async,
        url: documentUri,
        outputtype: toExtension.replace(".", ""),
        filetype: fromExtension.replace(".", ""),
        title: title,
        key: documentRevisionId
    };

    var uri = siteUrl + configServer.get('converterUrl');
    var headers = {
        'Content-Type': 'application/json'
    };

    if (cfgSignatureEnable && cfgSignatureUseForRequest) {
        headers[cfgSignatureAuthorizationHeader] = cfgSignatureAuthorizationHeaderPrefix + this.fillJwtByUrl(uri, params);
    }

    urllib.request(uri,
        {
            method: "POST",
            headers: headers,
            data: params
        },
        callback);
};

documentService.getExternalUri = function (fileStream, contentLength, contentType, documentRevisionId, callback) {
    documentRevisionId = documentService.generateRevisionId(documentRevisionId);

    var urlTostorage = siteUrl + configServer.get('storageUrl') + "?key=" + documentRevisionId;
    var headers = {
        "Content-Type": contentType == null ? "application/octet-stream" : contentType,
        "Content-Length": contentLength.toString(),
        "charset": "utf-8"
    };

    if (cfgSignatureEnable && cfgSignatureUseForRequest) {
        const hmac = jwa(cfgSignatureSecretAlgorithmRequest);
        var payloadhash = hmac.sign(fileStream, cfgSignatureSecret);
        headers[cfgSignatureAuthorizationHeader] = cfgSignatureAuthorizationHeaderPrefix + this.fillJwtByUrl(urlTostorage, undefined, undefined, payloadhash);
    }

    urllib.request(urlTostorage,
        {
            method: "POST",
            headers: headers,
            data: fileStream
        },
        function (err, data) {
            if (err) {
                callback();
                return;
            }
            var res = documentService.getResponseUri(data);
            callback(res.value);
        });
};

documentService.generateRevisionId = function (expectedKey) {
    if (expectedKey.length > 20) {
        expectedKey = expectedKey.hashCode().toString();
    }

    var key = expectedKey.replace(new RegExp("[^0-9-.a-zA-Z_=]", "g"), "_");

    return key.substring(0, Math.min(key.length, 20));
};

documentService.processConvertServiceResponceError = function (errorCode) {
    var errorMessage = "";
    var errorMessageTemplate = "Error occurred in the ConvertService: ";

    switch (errorCode) {
        case -20:
            errorMessage = errorMessageTemplate + "Error encrypt signature";
            break;
        case -8:
            errorMessage = errorMessageTemplate + "Error document signature";
            break;
        case -7:
            errorMessage = errorMessageTemplate + "Error document request";
            break;
        case -6:
            errorMessage = errorMessageTemplate + "Error database";
            break;
        case -5:
            errorMessage = errorMessageTemplate + "Error unexpected guid";
            break;
        case -4:
            errorMessage = errorMessageTemplate + "Error download error";
            break;
        case -3:
            errorMessage = errorMessageTemplate + "Error convertation error";
            break;
        case -2:
            errorMessage = errorMessageTemplate + "Error convertation timeout";
            break;
        case -1:
            errorMessage = errorMessageTemplate + "Error convertation unknown";
            break;
        case 0:
            break;
        default:
            errorMessage = "ErrorCode = " + errorCode;
            break;
    }

    throw { message: errorMessage };
};

documentService.getResponseUri = function (xml) {
    var json = documentService.convertXmlStringToJson(xml);

    if (!json.FileResult)
        throw { message: "FileResult node is null" };

    var fileResult = json.FileResult;

    if (fileResult.Error)
        documentService.processConvertServiceResponceError(parseInt(fileResult.Error[0]));

    if (!fileResult.EndConvert)
        throw { message: "EndConvert node is null" };

    var isEndConvert = fileResult.EndConvert[0].toLowerCase() === "true";

    if (!fileResult.Percent)
        throw { message: "Percent node is null" };

    var percent = parseInt(fileResult.Percent[0]);
    var uri = null;

    if (isEndConvert) {
        if (!fileResult.FileUrl)
            throw { message: "FileUrl node is null" };

        uri = fileResult.FileUrl[0];
        percent = 100;
    } else {
        percent = percent >= 100 ? 99 : percent;
    }

    return {
        key: percent,
        value: uri
    };
};

documentService.convertXmlStringToJson = function (xml) {
    var res;

    xml2js.parseString(xml, function (err, result) {
        res = result;
    });

    return res;
};

documentService.commandRequest = function (method, documentRevisionId, callback) {
    documentRevisionId = documentService.generateRevisionId(documentRevisionId);
    var params = {
        c: method,
        key: documentRevisionId
    };

    var uri = siteUrl + configServer.get('commandUrl');
    var headers = {
        'Content-Type': 'application/json'
    };
    if (cfgSignatureEnable && cfgSignatureUseForRequest) {
        headers[cfgSignatureAuthorizationHeader] = cfgSignatureAuthorizationHeaderPrefix + this.fillJwtByUrl(uri, params);
    }

    urllib.request(uri,
        {
            method: "POST",
            headers: headers,
            data: params
        },
        callback);
};

documentService.checkJwtHeader = function (req) {
  var decoded = null;
  var authorization = req.get(cfgSignatureAuthorizationHeader);
  if (authorization && authorization.startsWith(cfgSignatureAuthorizationHeaderPrefix)) {
    var token = authorization.substring(cfgSignatureAuthorizationHeaderPrefix.length);
    try {
      decoded = jwt.verify(token, cfgSignatureSecret);
    } catch (err) {
        console.log('checkJwtHeader error: name = ' + err.name + ' message = ' + err.message + ' token = ' + token)
    }
  }
  return decoded;
}

documentService.fillJwtByUrl = function (uri, opt_dataObject, opt_iss, opt_payloadhash) {
  var parseObject = urlModule.parse(uri, true);
  var payload = {query: parseObject.query, payload: opt_dataObject, payloadhash: opt_payloadhash};

  var options = {algorithm: cfgSignatureSecretAlgorithmRequest, expiresIn: cfgSignatureSecretExpiresIn, issuer: opt_iss};
  return jwt.sign(payload, cfgSignatureSecret, options);
}

module.exports = documentService;