Free online XLTX to DOTX conversion App via swift

How to Convert XLTX to DOTX on Swift: Step-by-Step Code Example

// Converting XLTX to HTML
let cellsApi = try CellsAPI(clientId: "YOUR_APP_SID", clientSecret: "YOUR_APP_KEY");
let expectation = self.expectation(description: "testcellsSaveAsPostDocumentSaveAs")
let name:String = file.XLTX
let saveOptions:SaveOptions? = SaveOptions(enableHTTPCompression: nil, saveFormat: "HTML", clearData: nil, cachedFileFolder: nil, validateMergedAreas: nil, refreshChartCache: nil, createDirectory: nil, sortNames: nil, calculateFormula: nil, checkFontCompatibility: nil, onePagePerSheet: true, compliance: nil, defaultFont: nil, printingPageType: nil, imageType: nil, desiredPPI: nil, jpegQuality: nil, securityOptions: nil)
let newfilename:String = "file"
let isAutoFitRows:Bool? = true
let isAutoFitColumns:Bool? = true
let folder:String = TEMPFOLDER
let storageName:String? = nil            
uploadFile(name: name) {
    CellsAPI.cellsSaveAsPostDocumentSaveAs(name: name, saveOptions: saveOptions, newfilename: newfilename, isAutoFitRows: isAutoFitRows, isAutoFitColumns: isAutoFitColumns, folder: folder, storageName: storageName)
    {
        (response, error) in
        guard error == nil else {
            let errorinfo = self.GetErrorDataInfo(error: error as! ErrorResponse)
            print("error info: \(errorinfo!)")
            return
        }

        if let response = response {
            expectation.fulfill()
        }
    }
}
self.waitForExpectations(timeout: testTimeout, handler: nil)

// Converting HTML to DOTX
let wordsApi = try WordsAPI(clientId: "YOUR_APP_SID", clientSecret: "YOUR_APP_KEY");
let fileName = "file";

// Save to HTML
let requestSaveOptionsData = HTMLSaveOptionsData().setFileName(fileName: BaseTestContext.getRemoteTestOut() + "/file.DOTX");
let request = SaveAsRequest(name: remoteName, saveOptionsData: requestSaveOptionsData as! PdfSaveOptionsData, folder: remoteFolder);
let actual = try wordsApi.saveAs(request: request);