Develop Reference

Downloading files in Blazor Webassembly when using navigation manager and needing to check user claims

I have a Blazor WASM solution in which I am trying to build functionality for downloading data from a (Radzen) datagrid. I start off by calling an export service from the code of my component like so:
await _exportService.Export("expense-claims-admin", type, new Query()
{
OrderBy = grid.Query.OrderBy,
Filter = grid.Query.Filter,
Select = "CreateDate,User.FirstName,User.LastName,Status,ExpenseRecords.Count AS NumberOfExpenseRecords,MileageRecords.Count AS NumberOfMileageRecords,TotalAmount"
});
My export service then runs the following code:
public async Task Export(string table, string type, Query query = null)
{
_navigationManager.NavigateTo(query != null ? query.ToUrl($"/export/{table}/{type}") : $"/export/{table}/{type}", true);
}
This calls a controller in my server project, which runs a different action depending on the request URL. For example:
[HttpGet("/export/expense-claims-admin/excel")]
public IActionResult ExportExpenseClaimsToExcelAdmin()
{
var claimsPrincipal = User;
var companyId = claimsPrincipal.FindFirst(c => c.Type == "companyId");
if (companyId != null)
{
return ToExcel(ApplyQuery(context.expense_claims.Where(x => x.DeleteDate == null && x.CompanyId == int.Parse(companyId.Value)), Request.Query));
}
//TODO - Return something other than null
return null!;
}
This then calls one of two methods depending on whether I'm trying to export to Excel or CSV. Below is the ToExcel method that gets called above:
public FileStreamResult ToExcel(IQueryable query, string fileName = null)
{
var columns = GetProperties(query.ElementType);
var stream = new MemoryStream();
using (var document = SpreadsheetDocument.Create(stream, SpreadsheetDocumentType.Workbook))
{
var workbookPart = document.AddWorkbookPart();
workbookPart.Workbook = new Workbook();
var worksheetPart = workbookPart.AddNewPart<WorksheetPart>();
worksheetPart.Worksheet = new Worksheet();
var workbookStylesPart = workbookPart.AddNewPart<WorkbookStylesPart>();
GenerateWorkbookStylesPartContent(workbookStylesPart);
var sheets = workbookPart.Workbook.AppendChild(new Sheets());
var sheet = new Sheet() { Id = workbookPart.GetIdOfPart(worksheetPart), SheetId = 1, Name = "Sheet1" };
sheets.Append(sheet);
workbookPart.Workbook.Save();
var sheetData = worksheetPart.Worksheet.AppendChild(new SheetData());
var headerRow = new Row();
foreach (var column in columns)
{
headerRow.Append(new Cell()
{
CellValue = new CellValue(column.Key),
DataType = new EnumValue<CellValues>(CellValues.String)
});
}
sheetData.AppendChild(headerRow);
foreach (var item in query)
{
var row = new Row();
foreach (var column in columns)
{
var value = GetValue(item, column.Key);
var stringValue = $"{value}".Trim();
var cell = new Cell();
var underlyingType = column.Value.IsGenericType &&
column.Value.GetGenericTypeDefinition() == typeof(Nullable<>) ?
Nullable.GetUnderlyingType(column.Value) : column.Value;
var typeCode = Type.GetTypeCode(underlyingType);
if (typeCode == TypeCode.DateTime)
{
if (!string.IsNullOrWhiteSpace(stringValue))
{
cell.CellValue = new CellValue() { Text = ((DateTime)value).ToOADate().ToString(System.Globalization.CultureInfo.InvariantCulture) };
cell.DataType = new EnumValue<CellValues>(CellValues.Number);
cell.StyleIndex = (UInt32Value)1U;
}
}
else if (typeCode == TypeCode.Boolean)
{
cell.CellValue = new CellValue(stringValue.ToLower());
cell.DataType = new EnumValue<CellValues>(CellValues.Boolean);
}
else if (IsNumeric(typeCode))
{
if (value != null)
{
stringValue = Convert.ToString(value, CultureInfo.InvariantCulture);
}
cell.CellValue = new CellValue(stringValue);
cell.DataType = new EnumValue<CellValues>(CellValues.Number);
}
else
{
cell.CellValue = new CellValue(stringValue);
cell.DataType = new EnumValue<CellValues>(CellValues.String);
}
row.Append(cell);
}
sheetData.AppendChild(row);
}
workbookPart.Workbook.Save();
}
if (stream?.Length > 0)
{
stream.Seek(0, SeekOrigin.Begin);
}
var result = new FileStreamResult(stream, "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
result.FileDownloadName = (!string.IsNullOrEmpty(fileName) ? fileName : "Export") + ".xlsx";
return result;
}
The issue I'm hitting is that the claims against the User object are never populated with the information that I need to do the checks in my export controller. I know this is because I'm calling the controller with navigation manager rather than going through a httpclient request so no authorisation token is passed, but if I use httpclient instead, the file is not downloaded by the browser.
I have tried using a combination of httpclient and javascript to get the file to download (code below) but this is returning a text file rather than an xlsx or csv file and the content is just gibberish (to me anyway).
Here's the code in my service if I use httpclient instead of navigation manager:
public async Task Export(string table, string type, Query query = null)
{
var response = await _client.GetAsync(query != null ? query.ToUrl($"/export/{table}/{type}") : $"/export/{table}/{type}");
var fileStream = await response.Content.ReadAsStreamAsync();
using var streamRef = new DotNetStreamReference(stream: fileStream);
await _js.InvokeVoidAsync("downloadFileFromStream", "Export", streamRef);
}
and here's the javascript code I'm using to download the file:
async function downloadFileFromStream(fileName, contentStreamReference) {
const arrayBuffer = await contentStreamReference.arrayBuffer();
const blob = new Blob([arrayBuffer]);
const url = URL.createObjectURL(blob);
triggerFileDownload(fileName, url);
URL.revokeObjectURL(url);
}
function triggerFileDownload(fileName, url) {
const anchorElement = document.createElement("a");
anchorElement.href = url;
if (fileName) {
anchorElement.download = fileName;
}
anchorElement.click();
anchorElement.remove();
}
I've read that using jsinterop to do file downloads is slow and that you're also limited by file size, so it seems like the best way to get this working would be to call the controller with navigation manager, but I just can't work out how to get those user claims if I do that and I really need to check those to make sure I'm returning the right data.

How to generate hash512 in pre-request from request that has {{variables}} in uri

So I m working on API when i need to set x-auth header for every request in PRE-REQUEST script.
I have variables in my request url i.e {{baseUrl}}{{basePath}}{{businessID}}/users?name={{userName}}......etc
I need to take whole address and add secretKey variable to the end of address, then get hash512 from it.
I was able to achieve that if i have no variables in my address i.e.: dummy.com/12321-e213-21-3e?name=John
I did this by :
var secret = "1234qwerHr2";
var url = request.url.slice(9); //sliced because I don't need to include baseUrl to hash
var hashedPayload = CryptoJS.enc.Hex.stringify(CryptoJS.SHA512(url+secret));
This will return the desired result.
Here is what I logged when trying the same code with variables
console.log(url); =>>>>>>> asePath}}{{businessID}}/users?name={{userName}}......etc
All variables defined , that`s for sure
Basically question is : how to get url with values of variables using var url = request.url; I need not {{businessID}}/users?name={{userName}} but 12321-e213-21-3e?name=John

I lost source where i found it. Somewhere on postman github issue thread
var secret = pm.globals.get("devSecretKey");
pm.myUtility = {
interpolateVariable: function (str) {
return str.replace(/\{\{([^}]+)\}\}/g, function (match, $1) {
// console.log(match)
let result = match; //default to return the exactly the same matchd variable string
if ($1) {
let realone = pm.variables.get($1);
if (realone) {
result = realone
}
}
return result;
});
},
getUrl: function () {
let url = pm.request.url.getRaw();
url = this.interpolateVariable(url)
let {
Url
} = require('postman-collection')
return new Url(url);
},
getUrlTest: function () {
let url = pm.request.url.getRaw();
url = this.interpolateVariable(url)
// let {
// Url
// } = require('postman-collection')
//return new Url(url);
return pm.request.url.parse(url);
}
}
var requestPath = pm.myUtility.getUrl().getPath();
var requestQuery =pm.myUtility.getUrl().getQueryString();
var hashedPayload = CryptoJS.enc.Hex.stringify(CryptoJS.SHA512(requestPath+"?"+requestQuery+secret)); //I added '?' because when you use getQueryString() i does not have '?' before query
pm.environment.set("tempAuthHash", hashedPayload);// use this in your header
This function he wrote is converting your {{variable}} to 'variableValue'
No need to change anything in his functions if you are not good with coding. Guy who created it has golden hands. Just place in your pre request

inDesign scripting: Include remote .js-file in script-file (and use it's variables)

I'm trying to access a remote .jsfile within an inDesign script to use it's variables. I found functions for including js-files locally but haven't found a good way to include.
http://remote-site.com/test.js:
var testVar = "it works!";
myscript.js, including locally (working):
app.doScript(new File("/Users/Popmouth/test.js"));
alert(testVar);
myscript.js, including locally including remotely (not working):
app.doScript(new File("http://remote-site.com/test.js"));
alert(testVar);
I also found this snippet, this alert works (alerts the content of the file, i.e. "var testVar = "it works!;") but I don't know how to use the vars in my alert function below:
var HTTPFile = function (url,port) {
if (arguments.length == 1) {
url = arguments[0];
port = 80;
};
this.url = url;
this.port = port;
this.httpPrefix = this.url.match(/http:\/\//);
this.domain = this.httpPrefix == null ? this.url.split("/")[0]+":"+this.port :this.url.split("/")[2]+":"+this.port;
this.call = "GET "+ (this.httpPrefix == null ? "http://"+this.url : this.url)+" HTTP/1.0\r\nHost:" +(this.httpPrefix == null ? this.url.split("/")[0] :this.url.split("/")[2])+"\r\nConnection: close\r\n\r\n";
this.reply = new String();
this.conn = new Socket();
this.conn.encoding = "binary";
HTTPFile.prototype.getFile = function(f) {
var typeMatch = this.url.match(/(\.)(\w{3,4}\b)/g);
if (this.conn.open(this.domain,"binary")) {
this.conn.write(this.call);
this.reply = this.conn.read(9999999999);
this.conn.close();
} else {
this.reply = "";
}
return this.reply.substr(this.reply.indexOf("\r\n\r\n")+4);;
};
}
var remoteFile = new HTTPFile("http://remote-site.com/test.js");
alert(.getFile());
This function

Ok, so I went to adobe-forums and got the following string which replaces app.doScript(new File("/Users/Popmouth/test.js"));:
var remoteCode = 'http://remote-site.com/test.js'; //location of your remote file
var script = app.doScript("do shell script \"curl 'remoteCode'\"".replace("remoteCode", remoteCode), ScriptLanguage.APPLESCRIPT_LANGUAGE);
// Set script args
app.scriptArgs.setValue("scriptArg1", "Hello");
// Set environmental vars
$.setenv("envVar1", "World");
// Run the "remote" script
app.doScript(script, ScriptLanguage.JAVASCRIPT);

Inject a JavaScript code in Webview iOS

I created a iOS web browser with swift language code. And add an extra button to inject a script on that web page, but it always crash when I try this:
webView!.evaluateJavaScript("document.body.style.background = 'red';", nil)
Any idea how to fix this? And how to read the JavaScript code from a file, and then inject it to that webview element.
I use the code style as this example but with WKWebView:
https://github.com/rshankras/WebViewDemo
If you can solve this question I need a basic working code in the answer. And solution for how to load the JavaScript from a file. And inject that code in the WKWebView element.

I don't see the method you are using (evaluateJavaScript) in the current UIWebView API docs but it is in the WKWebView docs. Maybe you are using the wrong API? Perhaps try using stringByEvaluatingJavaScriptFromString(_:) instead:
let script = "document.body.style.background = 'red'"
if let result = webView.stringByEvaluatingJavaScriptFromString(script) {
println("result is \(result)")
}
Also, i'm not sure if the "!" is needed (a hunch tells me it's not), as there is no context around your code. So maybe try both versions.
Getting a string from a file is something like:
let path = NSBundle.mainBundle().pathForResource("jsFileName", ofType: "js")
if let content = String.stringWithContentsOfFile(path, encoding: NSUTF8StringEncoding, error: nil) {
println("js content is \(content)")
}
Loading from disk has a lot of variables around how your file is being copied and stored so your going to have to do some work to fit the path variable to your structure.

This will work with WKWebView. Dont forget to add WebKit frame work on top on your class definition
var webView: WKWebView!
func loadWebViewWithCustomJavaScript {
//Create Preferences
let preferences = WKPreferences()
preferences.javaScriptEnabled = true
//Initialise javascript file with user content controller and configuration
let configuration = WKWebViewConfiguration()
let scriptURL = NSBundle.mainBundle().pathForResource("Your File Name", ofType: "js")
var scriptContent = ""
do {
scriptContent = try String(contentsOfFile: scriptURL!, encoding: NSUTF8StringEncoding)
} catch{
print("Cannot Load File")
}
let script = WKUserScript(source: scriptContent, injectionTime: .AtDocumentStart, forMainFrameOnly: true)
configuration.userContentController.addUserScript(script)
configuration.preferences = preferences
//Create WebView instance
webView = WKWebView(frame: CGRectMake(0,0, self.view.frame.size.width, self.view.frame.size.height), configuration: configuration)
view.addSubview(webView)
//Finally load the url
let url = NSURL(string:"your URL")
let urlRequest = NSURLRequest(URL: url!)
webView.loadRequest(urlRequest)
}
Sample JavaScript code for injection
//Hides name of "background1" element on the page
var styleTag = document.createElement("style");
styleTag.textContent = 'div#background1, .after-post.widget-area {display:none;}';
document.documentElement.appendChild(styleTag);

Got it working using following. Used String instead of NSString to use native swift 2. Javascript code to inject must be in hidesections.js file
let jsPath = NSBundle.mainBundle().pathForResource("hidesections", ofType: "js");
let jsContent: String?
do
{
jsContent = try String(contentsOfFile: jsPath!, encoding: NSUTF8StringEncoding)
}
catch _
{
jsContent = nil
}
webView.stringByEvaluatingJavaScriptFromString(jsContent!)

If you are using WKWebView here is a solution.
if let scriptFile = NSBundle.mainBundle().pathForResource("script", ofType: "js") {
var error: NSError?
let scriptString = NSString(contentsOfFile: scriptFile, encoding: NSUTF8StringEncoding, error: &error)
if let error = error {
println("Error: Could not load script file => \(error)")
} else {
if let scriptString = scriptString {
let script = WKUserScript(source: scriptString, injectionTime: .AtDocumentEnd, forMainFrameOnly: true)
let controller = WKUserContentController()
controller.addUserScript(script)
let configuration = WKWebViewConfiguration()
configuration.userContentController = controller
let webView = WKWebView(frame: self.view.bounds, configuration: configuration)
self.webView = webView
self.view.addSubview(webView)
}
}
}

Convert Node.JS code snippet to Javascript (Google Apps Script)

I would like to convert the following Node.JS code snippet to JavaScript in order to run it in Google Apps Script:
From: Node.JS
function getMessageSignature(path, request, nonce) {
var message = querystring.stringify(request);
var secret = new Buffer(config.secret, 'base64');
var hash = new crypto.createHash('sha256');
var hmac = new crypto.createHmac('sha512', secret);
var hash_digest = hash.update(nonce + message).digest('binary');
var hmac_digest = hmac.update(path + hash_digest, 'binary').digest('base64');
return hmac_digest;
}
This is the code I have tried so far (and many variations of it):
To: JavaScript / Google Apps Script
function getMessageSignature(url, request, nonce) {
// Message signature using HMAC-SHA512 of (URI path + SHA256(nonce + POST data))
//and base64 decoded secret API key
const secretApiKey = 'wdwdKswdKKewe23edeYIvL/GsltsGWbuBXnarcxZfu/9PjFbXl5npg==';
var secretApiKeyBytes = Utilities.base64Decode(secretApiKey);
var blob = Utilities.newBlob(secretApiKeyBytes);
var secretApiKeyString = blob.getDataAsString(); // POTENTIAL ERROR HERE?
var json = Utilities.jsonStringify(request);
var hash_digest = Utilities.computeDigest(Utilities.DigestAlgorithm.SHA_256,
nonce + json);
var hmac_digest = Utilities.computeHmacSignature(Utilities.MacAlgorithm.HMAC_SHA_512,
url + hash_digest, secretApiKeyString); // POTENTIAL ERROR HERE?
var base64 = Utilities.base64Encode(hmac_digest);
return base64;
}
When sending the signature as part of my request to the server, I always get the error message from the server: Invalid Key.
BTW: This is the API which I would like to use in JavaScript: Kraken API
I would appreciate any hint or suggestions very much!!

Solution:
Use jsSHA (https://github.com/Caligatio/jsSHA/) rather than Google App Script's functions. Create a new "jsSHA.gs" code file in Google App Script and copy/past in all the jsSHA optimised .js files from github.
function getKrakenSignature (path, postdata, nonce) {
var sha256obj = new jsSHA ("SHA-256", "BYTES");
sha256obj.update (nonce + postdata);
var hash_digest = sha256obj.getHash ("BYTES");
var sha512obj = new jsSHA ("SHA-512", "BYTES");
sha512obj.setHMACKey (api_key_private, "B64");
sha512obj.update (path);
sha512obj.update (hash_digest);
return sha512obj.getHMAC ("B64");
}
function getKrakenBalance () {
var path = "/0/private/Balance";
var nonce = new Date () * 1000;
var postdata = "nonce=" + nonce;
var signature = getKrakenSignature (path, postdata, nonce);
var url = api_url + path;
var options = {
method: 'post',
headers: {
'API-Key': api_key_public,
'API-Sign': signature
},
payload: postdata
};
var response = UrlFetchApp.fetch (url, options);
// ERROR handling
return response.getContentText ();
}

One problem is that querystring.stringify is not the same as Utilities.jsonStringify (which, FYI, is deprecated in favor of JSON.stringify).
I believe that this will be equivalent:
function queryStringify(obj) {
var params = [];
for(var key in obj) {
if(Object.hasOwnProperty(key)) {
if(typeof key === 'string') {
params.push([key, obj[key]]);
} else {
obj[key].forEach(function(val) {
params.push([key, val]);
});
}
}
}
return params.map(function(param) {
return encodeURIComponent(param[0]) + '=' + encodeURIComponent(param[1]);
}).join('&');
}
Though I am not sure if that is the reason you are seeing your error.

I noticed this nodejs to GS converter: https://www.npmjs.com/package/codegs
Haven't got the chance to use it, but it claims to handle 'require'-statements.