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Can I set the filename of a PDF object displayed in Chrome?

In my Vue app I receive a PDF as a blob, and want to display it using the browser's PDF viewer.
I convert it to a file, and generate an object url:
const blobFile = new File([blob], `my-file-name.pdf`, { type: 'application/pdf' })
this.invoiceUrl = window.URL.createObjectURL(blobFile)
Then I display it by setting that URL as the data attribute of an object element.
<object
:data="invoiceUrl"
type="application/pdf"
width="100%"
style="height: 100vh;">
</object>
The browser then displays the PDF using the PDF viewer. However, in Chrome, the file name that I provide (here, my-file-name.pdf) is not used: I see a hash in the title bar of the PDF viewer, and when I download the file using either 'right click -> Save as...' or the viewer's controls, it saves the file with the blob's hash (cda675a6-10af-42f3-aa68-8795aa8c377d or similar).
The viewer and file name work as I'd hoped in Firefox; it's only Chrome in which the file name is not used.
Is there any way, using native Javascript (including ES6, but no 3rd party dependencies other than Vue), to set the filename for a blob / object element in Chrome?
[edit] If it helps, the response has the following relevant headers:
Content-Type: application/pdf; charset=utf-8
Transfer-Encoding: chunked
Content-Disposition: attachment; filename*=utf-8''Invoice%2016246.pdf;
Content-Description: File Transfer
Content-Encoding: gzip

Chrome's extension seems to rely on the resource name set in the URI, i.e the file.ext in protocol://domain/path/file.ext.
So if your original URI contains that filename, the easiest might be to simply make your <object>'s data to the URI you fetched the pdf from directly, instead of going the Blob's way.
Now, there are cases it can't be done, and for these, there is a convoluted way, which might not work in future versions of Chrome, and probably not in other browsers, requiring to set up a Service Worker.
As we first said, Chrome parses the URI in search of a filename, so what we have to do, is to have an URI, with this filename, pointing to our blob:// URI.
To do so, we can use the Cache API, store our File as Request in there using our URL, and then retrieve that File from the Cache in the ServiceWorker.
Or in code,
From the main page
// register our ServiceWorker
navigator.serviceWorker.register('/sw.js')
.then(...
...
async function displayRenamedPDF(file, filename) {
// we use an hard-coded fake path
// to not interfere with legit requests
const reg_path = "/name-forcer/";
const url = reg_path + filename;
// store our File in the Cache
const store = await caches.open( "name-forcer" );
await store.put( url, new Response( file ) );
const frame = document.createElement( "iframe" );
frame.width = 400
frame.height = 500;
document.body.append( frame );
// makes the request to the File we just cached
frame.src = url;
// not needed anymore
frame.onload = (evt) => store.delete( url );
}
In the ServiceWorker sw.js
self.addEventListener('fetch', (event) => {
event.respondWith( (async () => {
const store = await caches.open("name-forcer");
const req = event.request;
const cached = await store.match( req );
return cached || fetch( req );
})() );
});
Live example (source)
Edit: This actually doesn't work in Chrome...
While it does set correctly the filename in the dialog, they seem to be unable to retrieve the file when saving it to the disk...
They don't seem to perform a Network request (and thus our SW isn't catching anything), and I don't really know where to look now.
Still this may be a good ground for future work on this.
And an other solution, I didn't took the time to check by myself, would be to run your own pdf viewer.
Mozilla has made its js based plugin pdf.js available, so from there we should be able to set the filename (even though once again I didn't dug there yet).
And as final note, Firefox is able to use the name property of a File Object a blobURI points to.
So even though it's not what OP asked for, in FF all it requires is
const file = new File([blob], filename);
const url = URL.createObjectURL(file);
object.data = url;

In Chrome, the filename is derived from the URL, so as long as you are using a blob URL, the short answer is "No, you cannot set the filename of a PDF object displayed in Chrome." You have no control over the UUID assigned to the blob URL and no way to override that as the name of the page using the object element. It is possible that inside the PDF a title is specified, and that will appear in the PDF viewer as the document name, but you still get the hash name when downloading.
This appears to be a security precaution, but I cannot say for sure.
Of course, if you have control over the URL, you can easily set the PDF filename by changing the URL.

I believe Kaiido's answer expresses, briefly, the best solution here:
"if your original URI contains that filename, the easiest might be to simply make your object's data to the URI you fetched the pdf from directly"
Especially for those coming from this similar question, it would have helped me to have more description of a specific implementation (working for pdfs) that allows the best user experience, especially when serving files that are generated on the fly.
The trick here is using a two-step process that perfectly mimics a normal link or button click. The client must (step 1) request the file be generated and stored server-side long enough for the client to (step 2) request the file itself. This requires you have some mechanism supporting unique identification of the file on disk or in a cache.
Without this process, the user will just see a blank tab while file-generation is in-progress and if it fails, then they'll just get the browser's ERR_TIMED_OUT page. Even if it succeeds, they'll have a hash in the title bar of the PDF viewer tab, and the save dialog will have the same hash as the suggested filename.
Here's the play-by-play to do better:
You can use an anchor tag or a button for the "download" or "view in browser" elements
Step 1 of 2 on the client: that element's click event can make a request for the file to be generated only (not transmitted).
Step 1 of 2 on the server: generate the file and hold on to it. Return only the filename to the client.
Step 2 of 2 on the client:
If viewing the file in the browser, use the filename returned from the generate request to then invoke window.open('view_file/<filename>?fileId=1'). That is the only way to indirectly control the name of the file as shown in the tab title and in any subsequent save dialog.
If downloading, just invoke window.open('download_file?fileId=1').
Step 2 of 2 on the server:
view_file(filename, fileId) handler just needs to serve the file using the fileId and ignore the filename parameter. In .NET, you can use a FileContentResult like File(bytes, contentType);
download_file(fileId) must set the filename via the Content-Disposition header as shown here. In .NET, that's return File(bytes, contentType, desiredFilename);
client-side download example:
download_link_clicked() {
// show spinner
ajaxGet(generate_file_url,
{},
(response) => {
// success!
// the server-side is responsible for setting the name
// of the file when it is being downloaded
window.open('download_file?fileId=1', "_blank");
// hide spinner
},
() => { // failure
// hide spinner
// proglem, notify pattern
},
null
);
client-side view example:
view_link_clicked() {
// show spinner
ajaxGet(generate_file_url,
{},
(response) => {
// success!
let filename = response.filename;
// simplest, reliable method I know of for controlling
// the filename of the PDF when viewed in the browser
window.open('view_file/'+filename+'?fileId=1')
// hide spinner
},
() => { // failure
// hide spinner
// proglem, notify pattern
},
null
);

I'm using the library pdf-lib, you can click here to learn more about the library.
I solved part of this problem by using api Document.setTitle("Some title text you want"),
Browser displayed my title correctly, but when click the download button, file name is still previous UUID. Perhaps there is other api in the library that allows you to modify download file name.

Chrome extension - saving PDF file

I'm developing a Chrome extension that will save files to the downloads folder (that's not all it's doing, but that's the part I have trouble with). Right now I'm focusing on PDF files. Basically, when a PDF is opened in Chrome, the user can manually save it using Menu -> Save File As ..., I'm just trying to automate this functionality using the extension, but I haven't found a good way to do it.
Let's say I can detect if the current tab has a PDF file in it (based on answers from this question).
The best thing I have figured out so far is to initiate a download:
chrome.downloads.download({
url: tabs[0].url, saveAs: false,
filename: "my file", /* This will be some unique autogenerated identifier */
conflictAction: "overwrite"
});
This works but has 2 drawbacks:
The file has to be re-downloaded, which is a pain if it's large. Besides, the file has been downloaded already so I should be able to use it.
For some reason this doesn't work with files opened locally ("file://..."). It throws a NETWORK_INVALID_REQUEST and doesn't download.
Is there a better way to save the file?

Note, chromium / chrome browsers appear to append embed element to document.body to display .pdf files
a) detecting pdf utilizing window.location.href , document.querySelectorAll("embed")[0].type;
b) utilizing XMLHttpRequest to request existing document, which should return pdf document as blob response, from cache; see console -> Network -> Headers -> Status Code
To allow opening file: protocol at chromium / chrome browsers, try utilizing command line flag --allow-access-from-files; see How do I make the Google Chrome flag “--allow-file-access-from-files” permanent?
At .pdf document , i.e.g; Ecma-262.pdf try
// check if `document` is `pdf`
if (/pdf/i.test(window.location.href.slice(-3))
|| document.querySelectorAll("embed")[0].type === "application/pdf") {
var xhr = new XMLHttpRequest();
// load `document` from `cache`
xhr.open("GET", "", true);
xhr.responseType = "blob";
xhr.onload = function (e) {
if (this.status === 200) {
// `blob` response
console.log(this.response);
var file = window.URL.createObjectURL(this.response);
var a = document.createElement("a");
a.href = file;
a.download = this.response.name
|| document.querySelectorAll("embed")[0].src
.split("/").pop();
document.body.appendChild(a);
a.click();
// remove `a` following `Save As` dialog,
// `window` regains `focus`
window.onfocus = function () {
Array.prototype.forEach.call(document.querySelectorAll("a")
, function (el) {
document.body.removeChild(el)
})
}
};
};
xhr.send();
};

Addressing only the file:// aspect of your problem. Does your extension have permission to access file://. In order to have access your extension both needs to ask for file:/// and user has to manually grant this access from the extensions page. You can check if you have the requisite permission using https://developer.chrome.com/extensions/extension#method-isAllowedFileSchemeAccess.
See Adding file://. permission to chrome extension for more information about accessing file:// urls. You may also find How can I enable my chrome extension in incognito mode? helpful.
For a related discussion (although not specific for your use case since you already have a PDF file), also see https://code.google.com/p/chromium/issues/detail?id=169337.

javascript read from a txt file and inject text into form

I apologize in the advance as I am a total beginner.
I have a pre-existing html form with text fields. I need to have a button that will allow me to upload a txt file (since when trying to look for answer about this, I learned javascript can't just access a file from my PC without me actively uploading it). Then I need the values from this txt file inserted into the text fields (for example, the form has: name, last name, phone etc - and the file will fill out this info).
I am going crazy trying to collect bits and pieces from other people's questions. any help would be greatly appreciated!

it depends on how you would like to have this handled, there are basically two options:
File Upload and page redirect
you could provide a file upload form to upload your textfile, redirect to the same page via form submission, handle the data on serverside (e.g. parse the file and get the values out of it) and let the server inject the values as default properties for the form file which is returned to the browser
XMLHttpRequest File Upload
in modern browsers, the native xhr object supports an upload property, so you could send the file via that upload property. it has to be sent to a serverside script that parses the file and returns the values in a fitting format, e.g. json (which would look like this: {'name':'somename', 'lastName':'someothername'}). then you have to register an eventlistener on completion of this upload (e.g. onload) and set these values on javascript side.
check this out for XMLHttpRequest upload (better solution in my opinion): https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/Using_XMLHttpRequest#Submitting_forms_and_uploading_files
edit:
well, the easiest solution would be just to provide a textfield and paste the content of the file into this field, hit a button and the content is parsed. then you wouldn't rely on network traffic or even a serverside handling, but could do everything with javascript, e.g. like this:
dom:
<textarea id="tf"></textarea>
<button id="parse">fill form!</button>
js:
var tf = document.getElementById("tf");
document.getElementById("parse").addEventListener("click", function(){
var formData = JSON.parse(tf.value);
//if your textfile is in json format, the formData object now has all values
});
edit: from the link i posted in the comments:
<!-- The HTML -->
<input id="the-file" name="file" type="file">
<button id="sendfile">send</button>
and
document.getElementById('sendfile').addEventListener("click", function(){
var fileInput = document.getElementById('the-file');
var file = fileInput.files[0];
var formData = new FormData();
formData.append('file', file);
var xhr = new XMLHttpRequest();
// Add any event handlers here...
xhr.open('POST', '/upload/path', true);
xhr.onreadystatechange = function(){
if(xhr.readyState == 4 && xhr.status == 200){
var values = JSON.parse(xhr.responseText);
//these are your input elements you want to fill!
formNameInput.setAttribute('value', values.name);
formFirstNameInput.setAttribute('value', values.firstName);
}
}
xhr.send(formData);
});
as already said, your serverside has to parse the file and respond with json

Load local file in Chrome App Webview

In Chrome packaged apps you can use to load external pages inside the app. Is there a way to make them load a local file (an html file inside the packaged app)? I can't use iframe, because iframe wont support external resources (scripts, images, whatever).

Don't have any code to show, but try this: Assuming you can read the local file (must use chrome.fileSystem.chooseEntry or have a retained entry on the file or its containing directory) and get a FileEntry object, you can then create a FileReader to get the file as a data URL. Then you can use that data URL directly in a webview. (Must have webview permission, in addition to the permissions needed to access the FileEntry.)
[Above is from memory while I'm eating breakfast. Might have some API names slightly off, but I hope you get the general idea.]

The local-resources sample has an example of loading an html file in a webview. You need to specify the files in the webview.partitions section of manifest.json.

You may try loading the file as a Blob via an XMLHttpRequest, then creating an object url to set it as webview's src attribute:
window.onload = function() {
var wv = document.getElementById("wv");
var xhr = new XMLHttpRequest();
xhr.open('GET', 'local_file.html', true);
xhr.responseType = 'blob';
xhr.onreadystatechange = function() {
if (xhr.readyState == 4 && xhr.status == 200) {
var blob = new Blob([this.response], {type: 'text/html'});
wv.src = window.URL.createObjectURL(blob);
}
};
xhr.send();
};
Here's a working example: chrome_app_webview_test.

Not exactly sure what you are looking for, but I have successfully used a <webview> tag pointing to a local .html file (including image and video resources) within the directory structure of an UNpackaged Chrome App. As its URL I simply use window.location.origin +'/files/my.html'. I leave my App unpackaged so I can dynamically generate the .html files. I guess you can pack the app if the content is static, but I have not tried.

HTML5: drag out a JS generated file

I have a feeling security concerns may not allow this but is it possible to generate a file with JavaScript and allow the user to drag it to the desktop (or file system)?
The following code drags out a file from a server
files[0].addEventListener("dragstart",function(evt){
evt.dataTransfer.setData("DownloadURL", "application/octet-stream:Eadui2.ttf:http://thecssninja.come/demo/gmail_dragout/Eadui.ttf");
},false);
And with the below code I can generate a file and have it download but I can't set the file name or let the user select the location.
var uriContent = "data:application/octet-stream," + encodeURIComponent(JSON.stringify(map));
location.href = uriContent;
Ideally I'd like a magical combination of both.

following code is currently working in Chrome only:
// generate downloadable URL, file name here will not affect stored file
var url = URL.createObjectURL(new File([JSON.stringify(map)], 'file_name.txt'));
// note that any draggable element may be used instead of files[0]
// since JSON.stringify returns a string, we use 'text' type in setData
files[0].addEventListener("dragstart", function(evt) {
evt.dataTransfer.setData("DownloadURL", "text:file_name.txt:" + url);
}, false);
now, dragging our files[0] element from the browser to desktop or file system, will store there a text file called, file_name.txt.
Feel free to choose another file name :)

This is only possible for Chrome, and even in Chrome you can't set the location. If using only Chrome is okay then you will have the following options:
Stick with Drag n' Drop like from the CSS Ninja's tutorial, then you should try Ben's answer. encodeURIComponent is one way, but if you have the file generated using BlobBuilder then you can use window.webkitURL.createObjectURL() to get the file's URL. You can also try using FileWriter() with requestFileSystem(TEMPORARY, ...).
Chrome supports download attribute for anchor tags so you can have regular link for the user to click (dragging also works):
Download
For cross browser support I suggest Downloadify.

You could try sending it to the server, saving the file, checking the return value and firing the download file function, followed by a server file that deletes the file from the server.
Something like this (with jQuery)
$.ajax({
url: 'saveFile.php',
method: 'post',
data: {
Filedata: data// file data variable
},
success: function(d) {
// save file function, where d is the filename
}
})
PHP:
$filename = ;//generate filename
file_put_contents($filename, $_POST['Filedata']);
echo $filename;
Obviously there is more to it but that should be the basics