I have a Flask web app with a URL route that receives a post request with some json, parses it to an .xlsx file, then returns the file with send_file().
Server side, I can see that the .xlsx file that is generated is correct but, once downloaded on the client side, the file is corrupted and can't be opened and is much larger than expected (201KB vs. 112KB).
I suspect it's some sort of encoding issue, but I've tried a whole bunch of stuff and can't make any headway. Can anyone help, please?
Flask route:
#app.route('/request/export_XLSX',methods=['POST'])
def request_export_XLSX():
json_model = json_util.loads(request.data.decode('ascii', 'ignore'))
xlsx_model = detox.xlsxFromJSONModel(json_model) # Returns file path
result = send_file(xlsx_model, as_attachment=True, attachment_filename=json_model['id']+'.xlsx', mimetype='application/vnd.ms-excel')
return result
JavaScript:
var exportModelExcel = function(){
var model = detox.fba.model
d3.selectAll('*').style("cursor","wait")
var modelJson = JSON.stringify(model)
$.ajax({
type: "POST",
url: "/request/export_XLSX",
data: modelJson,
success: function(d){
d3.selectAll('*').style("cursor","")
var blob = new Blob([d], {type: 'application/vnd.ms-excel'})
var link=document.createElement("a");
link.href=window.URL.createObjectURL(blob);
link.download=model.id+".xlsx";
link.click();
},
error: function(jqxhr,textStatus,errorThrown){
console.log("Error: " ,textStatus,errorThrown)
d3.selectAll('*').style("cursor","")
alert("There was an error exporting the model")
},
contentType: 'application/json',
responseType: 'blob',
processData: false,
});
}
Here's a link where you can see the good and bad .xlsx files: https://gofile.io/d/xywI1D
Well, I ended up ripping out the ajax and using an XMLHTTPRequest instead.
It works nicely and results in an uncorrupted .xlsx file. 🙂
var exportModelExcel = function(){
var model = detox.fba.model;
var modelJson = JSON.stringify(model);
var xhttp = new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
var downloadUrl = URL.createObjectURL(xhttp.response);
var a = document.createElement("a");
document.body.appendChild(a);
a.style = "display: none";
a.href = downloadUrl;
a.download = model.id+".xlsx";
a.click();
}
};
xhttp.open("POST", "/request/export_XLSX", true);
xhttp.setRequestHeader("Content-Type", "application/json");
xhttp.responseType = "blob";
xhttp.send(modelJson);
}
I have a PHP file that returns output in PDF - Works fine if I access the file directly.
I'd like to retrieve the PDF file through AJAX.
In native Javascript, it works fine:
var req = new XMLHttpRequest();
req.open("POST", "./api/pdftest.php?wpid="+wpid, true);
req.responseType = "blob";
req.onreadystatechange = function ()
{
if (req.readyState === 4 && req.status === 200)
{
var blob=req.response;
var filename = "test.pdf";
var link = document.createElement('a');
link.href = window.URL.createObjectURL(blob);
link.download = "test.pdf";
link.click();
var file = new File([blob], filename, { type: 'application/force-download' });
window.open(URL.createObjectURL(file));
}
};
req.send();
But I guess I'd use jQuery to ensure cross browser compatibility (although the snippet above works in Edge, Chrome and Firefox on pc, I haven't tested it in other browsers/on other platforms)
So I tried to rewrite the function:
url='./api/pdftest.php?wpid='+wpid;
$.ajax(
{
url: url,
method: 'POST',
responseType: 'blob',
success: function(data)
{
var filename='test.pdf';
var blob=new Blob([data]);
var filename = "test.pdf";
var link = document.createElement('a');
link.href = window.URL.createObjectURL(blob);
link.download = "test.pdf";
link.click();
var file = new File([blob], filename, { type: 'application/force-download' });
window.open(URL.createObjectURL(file));
}
});
The jQuery equivalent allows me to download a PDF file but … the PDF file is empty.
So I guess I am doing something wrong, probably in the DATA to BLOB conversion. But what? I hope somebody can see what I am doing wrong.
I've been using ages on StackOverflow, read many suggestions - but didn't find any answer. I simply can't see the forest for the trees.
Looking at the documentation for the jQuery.ajax() function, we see there's no setting called responseType, so you need to use xhrFields to directly set a property of the XHR object. And, since you're only setting the URL and success callback, we can just use the shorter jquery.post() function.
So the data is returned, we make a Blob and then a URL to download it. I'm not on Windows so I can't test if that link I constructed will work as expected, but figured I'd do it the jQuery way.
var url = './api/pdftest.php?wpid=' + wpid;
$.post({
url: url,
xhrFields: {responseType: "blob"},
success: function(data) {
// don't set the MIME type to pdf or it will display
var blob = new Blob([data], {type: "application/octet-stream"});
// build a blob URL
var bloburl = window.URL.createObjectURL(blob);
// trigger download for edge
var link = $("<a>").attr({href: bloburl, download: "test.pdf"}).click();
// trigger download for other browsers
window.open(bloburl);
}
});
Probably double!
This is the solution I found thanks to Hisham at Download pdf file using jquery ajax:
First, add the following plugin that can be used to the XHR V2 capabilities missing in JQuery: https://github.com/acigna/jquery-ajax-native
Then:
url='./api/pdftest.php?wpid='+wpid;
$.ajax(
{
dataType: 'native',
url: url,
xhrFields:
{
responseType: 'blob'
},
success: function(blob)
{
var filename = "test.pdf";
var link = document.createElement('a');
link.href = window.URL.createObjectURL(blob);
link.download = "test.pdf";
link.click();
var file = new File([blob], filename, { type: 'application/force-download' });
window.open(URL.createObjectURL(file));
}
});
This seems to be working.
Note: the window.open() is to make download possible in Firefox, the link.click() method Works in Edge, Chrome and Opera
Thanks to miken32 for pointing into the right direction.
As binary data is not possible to retrieve through jQuery.ajax, Native is the only way, at least for now. The following method works in Edge, Firefox, Chrome and Opera - tested on WIndows 10.
var req = new XMLHttpRequest();
req.open("POST", "./api/pdftest.php?wpid="+wpid, true);
req.responseType = "blob";
req.onreadystatechange = function ()
{
if (req.readyState === 4 && req.status === 200)
{
var blob=req.response;
var filename = "test.pdf";
var link = document.createElement('a');
link.setAttribute("type", "hidden"); // make it hidden if needed
link.href = window.URL.createObjectURL(blob);
link.download = "test.pdf";
document.body.appendChild(link);
link.click();
link.remove();
var file = new File([blob], filename, { type: 'application/force-download' });
//window.open(URL.createObjectURL(file));
}
};
req.send();
I have converted my existing data to text/csv and able to download the file in Chrome but when tried with Safari on iPad or Mac it opens a tab with name "unknown"/ "Untitled" . This is the code I am using -
var hiddenElement = document.createElement('a');
hiddenElement.href = 'data:text/csv,'+ encodeURI(response);
hiddenElement.target = '_blank';
hiddenElement.download = 'purchase.csv';
hiddenElement.click();
Is there anyway I can able to show the downloaded file as "purchase.csv" for safari.
Try this one
var a = document.createElement('a');
a.setAttribute("href",URL);
a.setAttribute("target", "_blank");
var dispatch = document.createEvent("HTMLEvents");
dispatch.initEvent("click", true, true);
a.dispatchEvent(dispatch);
return false;
IF the data is LOCAL -- Easy!
We just use window.URL.createObjectURL(). Let's set some globals...
//var response = Already defined by OP! Not sure what it is, but it's data to save.
var mimetype = "text/csv";
var filename = "purchase.csv";
Now we just set the header by means of the type argument to window.URL.createObjectURL()...
a.href = window.URL.createObjectURL(new Blob([response], {
encoding: "UTF-8",
type: mimetype + ";charset=UTF-8",
}));
IF the data is on the WEB -- Still easy, just more effort!
We can do this by means of XMLHTTPRequest() to download the file data, window.URL.createObjectURL() to cast the data to a blob type with MIME type headers, and then proceed normally in setting a.download = filename; and a.click();.
An abstract function for download file data directly to the JavaScript environment...
function load(url, callback) {
var xhr = new XMLHTTPRequest();
xhr.onreadystatechange = function () {
if (xhr.readyState === 4 && xhr.status === 200) callback(xhr.responseText);
};
xhr.open("GET", url, true);
}
Then download the data, build the link, and click it:
load("site.com/t.txt", function (contents) {
var a = window.document.createElement('a');
a.href = window.URL.createObjectURL(new Blob([response], {
encoding: "UTF-8",
type: mimetype + ";charset=UTF-8",
}));
a.download = filename;
document.body.appendChild(a);
a.click();
a.remove();
});
I have an action class that generates a PDF. The contentType is set appropriately.
public class MyAction extends ActionSupport
{
public String execute() {
...
...
File report = signedPdfExporter.generateReport(xyzData, props);
inputStream = new FileInputStream(report);
contentDisposition = "attachment=\"" + report.getName() + "\"";
contentType = "application/pdf";
return SUCCESS;
}
}
I call this action through an Ajax call. I don't know the way to deliver this stream to browser. I tried a few things but nothing worked.
$.ajax({
type: "POST",
url: url,
data: wireIdList,
cache: false,
success: function(response)
{
alert('got response');
window.open(response);
},
error: function (XMLHttpRequest, textStatus, errorThrown)
{
alert('Error occurred while opening fax template'
+ getAjaxErrorString(textStatus, errorThrown));
}
});
The above gives the error:
Your browser sent a request that this server could not understand.
Here is how I got this working
$.ajax({
url: '<URL_TO_FILE>',
success: function(data) {
var blob=new Blob([data]);
var link=document.createElement('a');
link.href=window.URL.createObjectURL(blob);
link.download="<FILENAME_TO_SAVE_WITH_EXTENSION>";
link.click();
}
});
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
Updated answer using download.js
$.ajax({
url: '<URL_TO_FILE>',
success: download.bind(true, "<FILENAME_TO_SAVE_WITH_EXTENSION>", "<FILE_MIME_TYPE>")
});
You don't necessarily need Ajax for this. Just an <a> link is enough if you set the content-disposition to attachment in the server side code. This way the parent page will just stay open, if that was your major concern (why would you unnecessarily have chosen Ajax for this otherwise?). Besides, there is no way to handle this nicely acynchronously. PDF is not character data. It's binary data. You can't do stuff like $(element).load(). You want to use completely new request for this. For that pdf is perfectly suitable.
To assist you more with the server side code, you'll need to tell more about the language used and post an excerpt of the code attempts.
I don't really think that any of the past answers spotted out the problem of the original poster. They all presume a GET request while the poster was trying to POST data and get a download in response.
In the course of searching for any better answer we found this jQuery Plugin for Requesting Ajax-like File Downloads (if link is broken sometime in the future, see the internet archive).
In its "heart" it creates a "temporary" HTML form containing the given data as input fields. This form is appended to the document and posted to the desired URL. Right after that the form is removed again:
jQuery('<form action="'+ url +'" method="'+ (method||'post') +'">'+inputs+'</form>')
.appendTo('body').submit().remove()
Update Mayur's answer looks pretty promising and very simple in comparison to the jQuery plug-in I referred to.
This is how i solve this issue.
The answer of Jonathan Amend on this post helped me a lot.
The example below is simplified.
For more details, the above source code is able to download a file using a JQuery Ajax request (GET, POST, PUT etc). It, also, helps to upload parameters as JSON and to change the content type to application/json (my default).
The html source:
<form method="POST">
<input type="text" name="startDate"/>
<input type="text" name="endDate"/>
<input type="text" name="startDate"/>
<select name="reportTimeDetail">
<option value="1">1</option>
</select>
<button type="submit"> Submit</button>
</form>
A simple form with two input text, one select and a button element.
The javascript page source:
<script type="text/javascript" src="JQuery 1.11.0 link"></script>
<script type="text/javascript">
// File Download on form submition.
$(document).on("ready", function(){
$("form button").on("click", function (event) {
event.stopPropagation(); // Do not propagate the event.
// Create an object that will manage to download the file.
new AjaxDownloadFile({
url: "url that returns a file",
data: JSON.stringify($("form").serializeObject())
});
return false; // Do not submit the form.
});
});
</script>
A simple event on button click. It creates an AjaxDownloadFile object. The AjaxDownloadFile class source is below.
The AjaxDownloadFile class source:
var AjaxDownloadFile = function (configurationSettings) {
// Standard settings.
this.settings = {
// JQuery AJAX default attributes.
url: "",
type: "POST",
headers: {
"Content-Type": "application/json; charset=UTF-8"
},
data: {},
// Custom events.
onSuccessStart: function (response, status, xhr, self) {
},
onSuccessFinish: function (response, status, xhr, self, filename) {
},
onErrorOccured: function (response, status, xhr, self) {
}
};
this.download = function () {
var self = this;
$.ajax({
type: this.settings.type,
url: this.settings.url,
headers: this.settings.headers,
data: this.settings.data,
success: function (response, status, xhr) {
// Start custom event.
self.settings.onSuccessStart(response, status, xhr, self);
// Check if a filename is existing on the response headers.
var filename = "";
var disposition = xhr.getResponseHeader("Content-Disposition");
if (disposition && disposition.indexOf("attachment") !== -1) {
var filenameRegex = /filename[^;=\n]*=(([""]).*?\2|[^;\n]*)/;
var matches = filenameRegex.exec(disposition);
if (matches != null && matches[1])
filename = matches[1].replace(/[""]/g, "");
}
var type = xhr.getResponseHeader("Content-Type");
var blob = new Blob([response], {type: type});
if (typeof window.navigator.msSaveBlob !== "undefined") {
// IE workaround for "HTML7007: One or more blob URLs were revoked by closing the blob for which they were created. These URLs will no longer resolve as the data backing the URL has been freed.
window.navigator.msSaveBlob(blob, filename);
} else {
var URL = window.URL || window.webkitURL;
var downloadUrl = URL.createObjectURL(blob);
if (filename) {
// Use HTML5 a[download] attribute to specify filename.
var a = document.createElement("a");
// Safari doesn"t support this yet.
if (typeof a.download === "undefined") {
window.location = downloadUrl;
} else {
a.href = downloadUrl;
a.download = filename;
document.body.appendChild(a);
a.click();
}
} else {
window.location = downloadUrl;
}
setTimeout(function () {
URL.revokeObjectURL(downloadUrl);
}, 100); // Cleanup
}
// Final custom event.
self.settings.onSuccessFinish(response, status, xhr, self, filename);
},
error: function (response, status, xhr) {
// Custom event to handle the error.
self.settings.onErrorOccured(response, status, xhr, self);
}
});
};
// Constructor.
{
// Merge settings.
$.extend(this.settings, configurationSettings);
// Make the request.
this.download();
}
};
I created this class to added to my JS library. It is reusable. Hope that helps.
What worked for me is the following code, as the server function is retrieving File(memoryStream.GetBuffer(), "application/pdf", "fileName.pdf");:
$http.get( fullUrl, { responseType: 'arraybuffer' })
.success(function (response) {
var blob = new Blob([response], { type: 'application/pdf' });
if (window.navigator && window.navigator.msSaveOrOpenBlob) {
window.navigator.msSaveOrOpenBlob(blob); // for IE
}
else {
var fileURL = URL.createObjectURL(blob);
var newWin = window.open(fileURL);
newWin.focus();
newWin.reload();
}
});
To fix the blank PDF issue in post request to get stream data like PDF, we need to add response type as 'arraybuffer' or 'blob' in request
$.ajax({
url: '<URL>',
type: "POST",
dataType: 'arraybuffer',
success: function(data) {
let blob = new Blob([data], {type: 'arraybuffer'});
let link = document.createElement('a');
let objectURL = window.URL.createObjectURL(blob);
link.href = objectURL;
link.target = '_self';
link.download = "fileName.pdf";
(document.body || document.documentElement).appendChild(link);
link.click();
setTimeout(()=>{
window.URL.revokeObjectURL(objectURL);
link.remove();
}, 100);
}
});
You could use this plugin which creates a form, and submits it, then removes it from the page.
jQuery.download = function(url, data, method) {
//url and data options required
if (url && data) {
//data can be string of parameters or array/object
data = typeof data == 'string' ? data : jQuery.param(data);
//split params into form inputs
var inputs = '';
jQuery.each(data.split('&'), function() {
var pair = this.split('=');
inputs += '<input type="hidden" name="' + pair[0] +
'" value="' + pair[1] + '" />';
});
//send request
jQuery('<form action="' + url +
'" method="' + (method || 'post') + '">' + inputs + '</form>')
.appendTo('body').submit().remove();
};
};
$.download(
'/export.php',
'filename=mySpreadsheet&format=xls&content=' + spreadsheetData
);
This worked for me. Found this plugin here
Concerning the answer given by Mayur Padshala this is the correct logic to download a pdf file via ajax but as others report in the comments this solution is indeed downloads a blank pdf.
The reason for this is explained in the accepted answer of this question: jQuery has some issues loading binary data using AJAX requests, as it does not yet implement some HTML5 XHR v2 capabilities, see this enhancement request and this discussion.
So using HTMLHTTPRequest the code should look like this:
var req = new XMLHttpRequest();
req.open("POST", "URL", true);
req.responseType = "blob";
req.onload = function (event) {
var blob = req.response;
var link=document.createElement('a');
link.href=window.URL.createObjectURL(blob);
link.download="name_for_the_file_to_save_with_extention";
link.click();
}
The following code worked for me
//Parameter to be passed
var data = 'reportid=R3823&isSQL=1&filter=[]';
var xhr = new XMLHttpRequest();
xhr.open("POST", "Reporting.jsp"); //url.It can pdf file path
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.responseType = "blob";
xhr.onload = function () {
if (this.status === 200) {
var blob = new Blob([xhr.response]);
const url = window.URL.createObjectURL(blob);
var a = document.createElement('a');
a.href = url;
a.download = 'myFile.pdf';
a.click();
setTimeout(function () {
// For Firefox it is necessary to delay revoking the ObjectURL
window.URL.revokeObjectURL(data)
, 100
})
}
};
xhr.send(data);
Hope this will save you a few hours and spare you from a headache.
It took me a while to figure this out, but doing regular $.ajax() request ruined my PDF file, while requesting it through address bar worked perfectly.
Solution was this:
Include download.js: http://danml.com/download.html
Then use XMLHttpRequest instead of $.ajax() request.
var ajax = new XMLHttpRequest();
ajax.open("GET", '/Admin/GetPdf' + id, true);
ajax.onreadystatechange = function(data) {
if (this.readyState == 4)
{
if (this.status == 200)
{
download(this.response, "report.pdf", "application/pdf");
}
else if (this.responseText != "")
{
alert(this.responseText);
}
}
else if (this.readyState == 2)
{
if (this.status == 200)
{
this.responseType = "blob";
}
else
{
this.responseType = "text";
}
}
};
ajax.send(null);
create a hidden iframe, then in your ajax code above:
url: document.getElementById('myiframeid').src = your_server_side_url,
and remove the window.open(response);
This snippet is for angular js users which will face the same problem, Note that the response file is downloaded using a programmed click event.
In this case , the headers were sent by server containing filename and content/type.
$http({
method: 'POST',
url: 'DownloadAttachment_URL',
data: { 'fileRef': 'filename.pdf' }, //I'm sending filename as a param
headers: { 'Authorization': $localStorage.jwt === undefined ? jwt : $localStorage.jwt },
responseType: 'arraybuffer',
}).success(function (data, status, headers, config) {
headers = headers();
var filename = headers['x-filename'];
var contentType = headers['content-type'];
var linkElement = document.createElement('a');
try {
var blob = new Blob([data], { type: contentType });
var url = window.URL.createObjectURL(blob);
linkElement.setAttribute('href', url);
linkElement.setAttribute("download", filename);
var clickEvent = new MouseEvent("click", {
"view": window,
"bubbles": true,
"cancelable": false
});
linkElement.dispatchEvent(clickEvent);
} catch (ex) {
console.log(ex);
}
}).error(function (data, status, headers, config) {
}).finally(function () {
});
I have found a solution that solved this problem for me (blank pdf when using jquery ajax). I've found this magical solution here: https://www.py4u.net/discuss/904599 (Answer 2) and it involves adding xhrFields to your ajax call:
xhrFields: {
responseType: 'blob'
}
My working example:
$.ajax({
url: "myUrl",
type: 'GET',
headers: {"token": mySecurityToken},
xhrFields: {
responseType: 'blob'
},
data: {id: myId}
}).done(function( data, statusText, xhr ) {
var filename = "";
var disposition = xhr.getResponseHeader("Content-Disposition");
if (disposition && (disposition.indexOf("attachment") !== -1) || disposition.indexOf("filename") !== -1) {
var filenameRegex = /filename[^;=\n]*=(([""]).*?\2|[^;\n]*)/;
var matches = filenameRegex.exec(disposition);
if (matches != null && matches[1])
filename = matches[1].replace(/[""]/g, "");
}
var type = xhr.getResponseHeader("Content-Type");
var blob = new Blob([data], {type: type});
if (typeof window.navigator.msSaveBlob !== "undefined") {
// IE workaround for "HTML7007: One or more blob URLs were revoked by closing the blob for which they were created. These URLs will no longer resolve as the data backing the URL has been freed.
window.navigator.msSaveBlob(blob, filename);
} else {
var URL = window.URL || window.webkitURL;
var downloadUrl = URL.createObjectURL(blob);
if (filename) {
// Use HTML5 a[download] attribute to specify filename.
var a = document.createElement("a");
// Safari doesn"t support this yet.
if (typeof a.download === "undefined") {
window.location = downloadUrl;
} else {
a.href = downloadUrl;
a.download = filename;
document.body.appendChild(a);
a.click();
}
} else {
window.location = downloadUrl;
}
setTimeout(function () {
URL.revokeObjectURL(downloadUrl);
}, 100); // Cleanup
}
})
I hope this will solve this nasty issue for many of you.
var xhr;
var beforeSend = function(){
$('#pleasewaitDL').modal('show');
}
$(function () {
$('#print_brochure_link').click(function(){
beforeSend();
xhr = new XMLHttpRequest();
xhr.open("GET",$('#preparedPrintModalForm').attr('action'), true);
xhr.responseType = "blob";
xhr.onload = function (e) {
if (this.status === 200) {
var file = window.URL.createObjectURL(this.response);
var a = document.createElement("a");
a.href = file;
a.download = this.response.name || "Property Brochure";
console.log(file);
document.body.appendChild(a);
a.click();
window.onfocus = function () {
document.body.removeChild(a)
}
$('#pleasewaitDL').modal('hide');
};
};
xhr.send($('#preparedPrintModalForm').serialize());
});
$('#pleasewaitDLCancel').click(function() {
xhr.abort();
});
});
If you have to work with file-stream (so no physically saved PDF) like we do and you want to download the PDF without page-reload, the following function works for us:
HTML
<div id="download-helper-hidden-container" style="display:none">
<form id="download-helper-form" target="pdf-download-output" method="post">
<input type="hidden" name="downloadHelperTransferData" id="downloadHelperTransferData" />
</form>
<iframe id="pdf-helper-output" name="pdf-download-output"></iframe>
</div>
Javascript
var form = document.getElementById('download-helper-form');
$("#downloadHelperTransferData").val(transferData);
form.action = "ServerSideFunctionWhichWritesPdfBytesToResponse";
form.submit();
Due to the target="pdf-download-output", the response is written into the iframe and therefore no page reload is executed, but the pdf-response-stream is output in the browser as a download.
100% OK for all file types
// download the file
var link = document.createElement('a'),
filename = fname;
link.href = URL.createObjectURL(data);
link.download = filename;
link.click();
Do you have to do it with Ajax? Couldn't it be a possibility to load it in an iframe?
The best usage is to do an anchor or a form with the provided link, but it you need to do a validation or in other cases using jquery the best usage is to add a form and submit it using jquery (don't forget to set your request disposition as attachement on server side).
<form id="pdf-form" action="/link_to/download_your.pdf" accept-charset="UTF-8" method="get">
<input type="hidden" name="data" id="data" value="your data"></form>
and
Download my Pdf
then in jquery
$('#pdf').click(function () {
// your data if it json do it like this JSON.stringify(your_data_as_json)
$('#data').val(data);
$('#pdf-form').submit();
})