Short version
I have a webapp using Magnolia, I need to upload a comment with posibility of multiple files, I want to use AJAX, before saving the files as assets I want to be able to check the user's permission, I figured I need a custom Java-based REST endpoint, I made it work, but I have issues saving "jcr:data" into an asset.
Long version
I have a webapp, I have registered users (using PUR), I have different roles for users (for simplicity let's say User and Editor) and I have a Post and a Comment content types. Every User can create a Post and add files, every Post holds the creator's UUID, array of Comment UUIDs and array of file UUIDs (from Assets app), every Post has a comment section and every Comment can have files attached (zero or multiple) to it. Every Editor can post a comment to every Post, but Users can only post comments to their own Posts.
My form for comments looks something like this:
<form action="" method="post" id="comment-form" enctype="multipart/form-data">
<input type="file" name="file" id="file" multiple />
<textarea name="text"></textarea>
<button type="button" onclick="sendComment();">Send</button>
</form>
I tried using Javascript model to process the data and I was able to save the asset correctly, however only one. I couldn't access the other files in the model.
I tried solving it (and improving user experience) by using AJAX and a REST endpoint. I opted not to use the Nodes endpoint API, because I didn't know how to solve the permission issue. I know I can restrict access to REST for each role, but not based on ownership of the Post. So I created my own Java-based endpoint (copied from documentation).
In the sendComment() function in Javascript I create an object with properties like name, extension, mimeType, ..., and data. I read in the documentation that you should send the data using the Base64 format, so I used FileReader() to accomplish that:
var fileObject = {
// properties like name, extension, mimeType, ...
}
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
// this part is easy
};
xhttp.open("PUT", "http://localhost:8080/myApp/.rest/assets/v1/saveAsset", true);
xhttp.setRequestHeader("Content-type", "application/json");
var reader = new FileReader();
reader.onload = function() {
fileObject.data = reader.result;
// I also tried without the 'data:image/png;base64,' part by reader.result.split(",")[1];
xhttp.send(JSON.stringify(fileObject));
};
reader.readAsDataURL(file); //where file is the value of the input element.files[i]
In Java I created a POJO class that has the same properties as the javascript object. Including a String data.
The code for the endpoint looks like this:
public Response saveAsset(Asset file) {
// Asset is my custom POJO class
Session damSession;
Node asset;
Node resource;
try {
damSession = MgnlContext.getJCRSession("dam");
asset = damSession.getRootNode().addNode(file.getName(), "mgnl:asset");
asset.setProperty("name", file.getName());
asset.setProperty("type", file.getExtension());
resource = asset.addNode("jcr:content", "mgnl:resource");
InputStream dataStream = new ByteArrayInputStream(file.getData().getBytes());
ValueFactory vf = damSession.getValueFactory();
Binary dataBinary = vf.createBinary(dataStream);
resource.setProperty("jcr:data", dataBinary);
resource.setProperty("fileName", file.getName());
resource.setProperty("extension", file.getExtension());
resource.setProperty("size", file.getSize());
resource.setProperty("jcr:mimeType", file.getMimeType());
damSession.save();
return Response.ok(LinkUtil.createLink(asset)).build();
} catch (RepositoryException e) {
return Response.ok(e.getMessage()).build(); //I know it's not ok, but that's not important at the moment
}
}
The asset gets created, the properties get saved apart from the jcr:data. If I upload an image and then download it either by the link I get as a response or directly from the Assets app, it cannot be opened, I get the format is not supported message. The size is 0, image doesn't show in the Assets app, seems like the data is simply not there, or it's in the wrong format.
How can I send the file or the file data to the Java endpoint? And how should I receive it? Does anybody know what am I missing? I honestly don't know what else to do with it.
Thank you
The input stream had to be decoded from Base64.
InputStream dataStream = new ByteArrayInputStream(Base64.decodeBase64(file.getData().getBytes()));
...and it only took me less than 3 months.
Noticed it after going through the source code for REST module that for unmarshalling Binary Value it had to be encoded to Base64, so I tried decoding it and it started to work.
Test browser:
Version of Chrome: 52.0.2743.116
It is a simple javascript that is to open an image file from local like 'C:\002.jpg'
function run(){
var URL = "file:///C:\002.jpg";
window.open(URL, null);
}
run();
Here is my sample code.
https://fiddle.jshell.net/q326vLya/3/
Please give me any suitable suggestions.
We use Chrome a lot in the classroom and it is a must to working with local files.
What we have been using is "Web Server for Chrome". You start it up, choose the folder wishing to work with and go to URL (like 127.0.0.1:port you chose)
It is a simple server and cannot use PHP but for simple work, might be your solution:
https://chrome.google.com/webstore/detail/web-server-for-chrome/ofhbbkphhbklhfoeikjpcbhemlocgigb
1)
Open your terminal and type
npm install -g http-server
2)
Go to the root folder that you want to serve you files and type:
http-server ./
3)
Read the output of the terminal, something kinda http://localhost:8080 will appear.
Everything on there will be allowed to be got.
Example:
background: url('http://localhost:8080/waw.png');
Okay folks, I completely understand the security reasons behind this error message, but sometimes, we do need a workaround... and here's mine. It uses ASP.Net (rather than JavaScript, which this question was based on) but it'll hopefully be useful to someone.
Our in-house app has a webpage where users can create a list of shortcuts to useful files spread throughout our network. When they click on one of these shortcuts, we want to open these files... but of course, Chrome's error prevents this.
This webpage uses AngularJS 1.x to list the various shortcuts.
Originally, my webpage was attempting to directly create an <a href..> element pointing at the files, but this produced the "Not allowed to load local resource" error when a user clicked on one of these links.
<div ng-repeat='sc in listOfShortcuts' id="{{sc.ShtCut_ID}}" class="cssOneShortcutRecord" >
<div class="cssShortcutIcon">
<img ng-src="{{ GetIconName(sc.ShtCut_PathFilename); }}">
</div>
<div class="cssShortcutName">
<a ng-href="{{ sc.ShtCut_PathFilename }}" ng-attr-title="{{sc.ShtCut_Tooltip}}" target="_blank" >{{ sc.ShtCut_Name }}</a>
</div>
</div>
The solution was to replace those <a href..> elements with this code, to call a function in my Angular controller...
<div ng-click="OpenAnExternalFile(sc.ShtCut_PathFilename);" >
{{ sc.ShtCut_Name }}
</div>
The function itself is very simple...
$scope.OpenAnExternalFile = function (filename) {
//
// Open an external file (i.e. a file which ISN'T in our IIS folder)
// To do this, we get an ASP.Net Handler to manually load the file,
// then return it's contents in a Response.
//
var URL = '/Handlers/DownloadExternalFile.ashx?filename=' + encodeURIComponent(filename);
window.open(URL);
}
And in my ASP.Net project, I added a Handler file called DownloadExternalFile.aspx which contained this code:
namespace MikesProject.Handlers
{
/// <summary>
/// Summary description for DownloadExternalFile
/// </summary>
public class DownloadExternalFile : IHttpHandler
{
// We can't directly open a network file using Javascript, eg
// window.open("\\SomeNetworkPath\ExcelFile\MikesExcelFile.xls");
//
// Instead, we need to get Javascript to call this groovy helper class which loads such a file, then sends it to the stream.
// window.open("/Handlers/DownloadExternalFile.ashx?filename=//SomeNetworkPath/ExcelFile/MikesExcelFile.xls");
//
public void ProcessRequest(HttpContext context)
{
string pathAndFilename = context.Request["filename"]; // eg "\\SomeNetworkPath\ExcelFile\MikesExcelFile.xls"
string filename = System.IO.Path.GetFileName(pathAndFilename); // eg "MikesExcelFile.xls"
context.Response.ClearContent();
WebClient webClient = new WebClient();
using (Stream stream = webClient.OpenRead(pathAndFilename))
{
// Process image...
byte[] data1 = new byte[stream.Length];
stream.Read(data1, 0, data1.Length);
context.Response.AddHeader("Content-Disposition", string.Format("attachment; filename={0}", filename));
context.Response.BinaryWrite(data1);
context.Response.Flush();
context.Response.SuppressContent = true;
context.ApplicationInstance.CompleteRequest();
}
}
public bool IsReusable
{
get
{
return false;
}
}
}
And that's it.
Now, when a user clicks on one of my Shortcut links, it calls the OpenAnExternalFile function, which opens this .ashx file, passing it the path+filename of the file we want to open.
This Handler code loads the file, then passes it's contents back in the HTTP response.
And, job done, the webpage opens the external file.
Phew ! Again - there is a reason why Chrome throws this "Not allowed to load local resources" exception, so tread carefully with this... but I'm posting this code just to demonstrate that this is a fairly simple way around this limitation.
Just one last comment: the original question wanted to open the file "C:\002.jpg". You can't do this. Your website will sit on one server (with it's own C: drive) and has no direct access to your user's own C: drive. So the best you can do is use code like mine to access files somewhere on a network drive.
Chrome specifically blocks local file access this way for security reasons.
Here's an article to workaround the flag in Chrome (and open your system up to vulnerabilities):
http://www.chrome-allow-file-access-from-file.com/
There is a workaround using Web Server for Chrome. Here are the steps:
Add the Extension to chrome.
Choose the folder (C:\images) and launch the server
on your desired port.
Now easily access your local file:
function run(){
// 8887 is the port number you have launched your serve
var URL = "http://127.0.0.1:8887/002.jpg";
window.open(URL, null);
}
run();
PS: You might need to select the CORS Header option from advanced setting incase you face any cross origin access error.
This issue come when I am using PHP as server side language and the work around was to generate base64 enconding of my image before sending the result to client
$path = 'E:/pat/rwanda.png';
$type = pathinfo($path, PATHINFO_EXTENSION);
$data = file_get_contents($path);
$base64 = 'data:image/' . $type . ';base64,' . base64_encode($data);
I think may give someone idea to create his own work around
Thanks
Google Chrome does not allow to load local resources because of the security. Chrome need http url. Internet Explorer and Edge allows to load local resources, but Safari, Chrome, and Firefox doesn't allows to load local resources.
Go to file location and start the Python Server from there.
python -m SimpleHttpServer
then put that url into function:
function run(){
var URL = "http://172.271.1.20:8000/" /* http://0.0.0.0:8000/ or http://127.0.0.1:8000/; */
window.open(URL, null);
}
If you have php installed - you can use built-in server. Just open target dir with files and run
php -S localhost:8001
If you could do this, it will represent a big security problem, as you can access your filesystem, and potentially act on the data available there... Luckily it's not possible to do what you're trying to do.
If you need local resources to be accessed, you can try to start a web server on your machine, and in this case your method will work. Other workarounds are possible, such as acting on Chrome settings, but I always prefer the clean way, installing a local web server, maybe on a different port (no, it's not so difficult!).
See also:
Open local files(file://) using Chrome
Opening local files from chrome
You just need to replace all image network paths to byte strings in stored Encoded HTML string.
For this you required HtmlAgilityPack to convert Html string to Html document.
https://www.nuget.org/packages/HtmlAgilityPack
Find Below code to convert each image src network path(or local path) to byte sting.
It will definitely display all images with network path(or local path) in IE,chrome and firefox.
string encodedHtmlString = Emailmodel.DtEmailFields.Rows[0]["Body"].ToString();
// Decode the encoded string.
StringWriter myWriter = new StringWriter();
HttpUtility.HtmlDecode(encodedHtmlString, myWriter);
string DecodedHtmlString = myWriter.ToString();
//find and replace each img src with byte string
HtmlDocument document = new HtmlDocument();
document.LoadHtml(DecodedHtmlString);
document.DocumentNode.Descendants("img")
.Where(e =>
{
string src = e.GetAttributeValue("src", null) ?? "";
return !string.IsNullOrEmpty(src);//&& src.StartsWith("data:image");
})
.ToList()
.ForEach(x =>
{
string currentSrcValue = x.GetAttributeValue("src", null);
string filePath = Path.GetDirectoryName(currentSrcValue) + "\\";
string filename = Path.GetFileName(currentSrcValue);
string contenttype = "image/" + Path.GetExtension(filename).Replace(".", "");
FileStream fs = new FileStream(filePath + filename, FileMode.Open, FileAccess.Read);
BinaryReader br = new BinaryReader(fs);
Byte[] bytes = br.ReadBytes((Int32)fs.Length);
br.Close();
fs.Close();
x.SetAttributeValue("src", "data:" + contenttype + ";base64," + Convert.ToBase64String(bytes));
});
string result = document.DocumentNode.OuterHtml;
//Encode HTML string
string myEncodedString = HttpUtility.HtmlEncode(result);
Emailmodel.DtEmailFields.Rows[0]["Body"] = myEncodedString;
Chrome and other Browser restrict the access of a server to local files due to security reasons. However you can open the browser in allowed access mode. Just open the terminal and go to the folder where chrome.exe is stored and write the following command.
chrome.exe --allow-file-access-from-files
Read this for more details
This way, However, didn't work for me so I made a different route for every file in a particular directory. Therefore, going to that path meant opening that file.
function getroutes(list){
list.forEach(function(element) {
app.get("/"+ element, function(req, res) {
res.sendFile(__dirname + "/public/extracted/" + element);
});
});
}
I called this function passing the list of filename in the directory __dirname/public/extracted and it created a different route for each filename which I was able to render on server side.
This is for google-chrome-extension
const url = "file:///C:\002.jpg"
chrome.tabs.create({url, active:true})
manifest.json
{
"name": "",
"manifest_version": 3,
"permissions": [
"activeTab",
"tabs"
],
// ...
}
This solution worked for me in PHP. It opens the PDF in the browser.
// $path is the path to the pdf file
public function showPDF($path) {
if($path) {
header("Content-type: application/pdf");
header("Content-Disposition: inline; filename=filename.pdf");
#readfile($path);
}
}
I've encounterd this problem, and here is my solution for Angular, I wrapped my Angular's asset folder in encodeURIComponent() function. It worked. But still, I'd like to know more about the risk of this solution if there's any:
```const URL = ${encodeURIComponent(/assets/office/file_2.pdf)}
window.open(URL)
I used Angular 9, so this is my url when I clicked open local file:
```http://localhost:4200/%2Fassets%2Foffice%2Ffile_2.pdf```
In the case of audio files, when you give <audio src="C://somePath"/>, this throws an error saying cannot load local resource.
This makes sense because any webpage can't simply give a local path and access your private files.
In case you are trying to play audio with dynamic paths, by changing src property through JS, then here is a sample implementation using Flask server and HTML.
server.py
#app.route("/")
def home():
return render_template('audioMap.html')
#app.route('/<audio_file_name>')
def view_method(audio_file_name):
path_to_audio_file = "C:/Audios/yourFolderPath" + audio_file_name
return send_file(
path_to_audio_file,
mimetype="audio/mp3",
as_attachment=True,
attachment_filename="test.mp3")
audioMap.html
{% raw %}
<!DOCTYPE html>
<html>
<body>
AUDIO: <audio src="Std.mp3" controls >
</body>
</html>
{% endraw %}
Explanation:
When you give the audio file name under src property, this creates a get request in the flask as shown
127.0.0.1 - - [04/May/2021 21:33:12] "GET /Std.mp3 HTTP/1.1" 200 -
As you can see that, the flask has sent a Get request for the Std.mp3 file. So to serve this get request, we wrote an endpoint that takes the audio file name, reads it from the local directory, and returns it back. Hence the audio shows up on UI.
Note: This works only if you are rendering your HTML file using the
render_template method via flask or to say, using flask as your web server.
Google Chrome does not allow to load local resources because of the security .
There is a simple solution for this problem .
1.install live-server plugin in vscode
2.open the html file by live-server
I am creating a node.js app in which user can upload files and can download later.
I am storing file information (original file name that user uploaded, ...) in mongodb document and named that file same as mongodb document id. Now i want my user to be able to download that file with the original file name.
What i want to know is when a user sends a GET request on http://myapp.com/mongoDocument_Id
user gets a file named myOriginalfile.ext
I know about node-static and other modules but i can't rename them before sending file.
i am using koa.js framework.
Here's a simple example using koa-file-server:
var app = require('koa')();
var route = require('koa-route');
var send = require('koa-file-server')({ root : './static' }).send;
app.use(route.get('/:id', function *(id) {
// TODO: perform lookup from id to filename here.
// We'll use a hardcoded filename as an example.
var filename = 'test.txt';
// Set the looked-up filename as the download name.
this.attachment(filename);
// Send the file.
yield send(this, id);
}));
app.listen(3012);
In short:
the files are stored in ./static using the MongoDB id as their filename
a user requests http://myapp.com/123456
you look up that ID in MongoDB to find out the original filename (in the example above, the filename is just hardcoded to test.txt)
the file ./static/123456 is offered as a download using the original filename set in the Content-Disposition header (by using this.attachment(filename)), which will make the browser store it locally as test.txt instead of 123456.
How can I upload a file in azure if I only have the URL of the file to upload. In this case, i 'm using Dropbox file chooser which selects file from dropbox and returns its url path.
eq
https://www.dropbox.com/s/o9myet72y19iaan/Getting%20Started.pdf
Now we need the file to be stored in Windows Azure blob. What is the easiest way to do this without downloading the file first.
I'm planning to use a asp.net web api for the uploading of file to azure blob.
At first, I thought it should be quite straight forward as Azure Blob Storage support copying blobs from external URL however I don't think this would work in case of Dropbox files. I just tried it and got an error even though.
The link you mentioned above is not the direct link to the file. It's a link to a page on Dropbox's website from where you can download a file. This is obviously you don't want. Here's an alternate solution which you can try:
Replace www.dropbox.com in your URL with dl.dropboxusercontent.com (based on #smarx's comments below) and use that URL in the following code:
First you would need to append dl=1 to your request URL as query string. So your Dropbox URL would be https://www.dropbox.com/s/o9myet72y19iaan/Getting%20Started.pdf?dl=1. dl query string parameter indicates the file needs to be downloaded.
Next, using HTTPWebRequest try accessing this URL. Dropbox will respond back with another link and 302 status code. This link would be something like https://dl.dropboxusercontent.com/s/o9myet72y19iaan/Getting%20Started.pdf?token_hash=<tokenhash>.
Use this link in the code below to copy file. This would work.
CloudStorageAccount acc = new CloudStorageAccount(new StorageCredentials("account", "key"), false);
var client = acc.CreateCloudBlobClient();
var container = client.GetContainerReference("container-name");
container.CreateIfNotExists();
var blob = container.GetBlockBlobReference("dropbox-file-name");
blob.StartCopyFromBlob(new Uri("dropbox URL with dl.dropboxusercontent.com"));
Console.WriteLine("Copy request accepted");
Console.WriteLine("Now checking for copy state");
bool continueLoop = true;
do
{
blob.FetchAttributes();
var copyState = blob.CopyState;
switch (copyState.Status)
{
case CopyStatus.Pending:
Console.WriteLine("Copy is still pending. Will check status again after 1 second.");
System.Threading.Thread.Sleep(1000);//Copy is still pending...check after 1 second
break;
default:
Console.WriteLine("Terminating process with copy state = " + copyState.Status);
continueLoop = false;
break;
}
}
while (continueLoop);
Console.WriteLine("Press any key to continue.");