Develop Reference

Occasionally uploading larger files

On moving to the next step in the form I have run some checks. One is to stop photos over 10mb and preventing .heic files from being upload. 90% of the time it works, but now and again files are let through.
Any help with a better written solution or a reason why this may fail and let large files or .heic file through.
var upload_one = document.getElementById("image_one");
if(upload_one.files.length > 0) {
if (upload_one.files.item(0).size >= '10485760') {
upload_one.className += " invalid";
valid = false;
alert("Photo is too large. Photos need to be under 10mb")
}
fileName = document.querySelector('#image_one').value;
extension = fileName.split('.').pop();
if (extension == 'heic') {
upload_one.className += " invalid";
valid = false;
alert("Files can only be .png, .jpg or .jpeg")
}
}

You should have a look at presigned Url using S3 bucket on aws.
Basically you generate an upload url where you can upload big files direclty to S3.
Personally I use a lambda to generate this presignedUrl and I return it to front end then.
Backend
const AWS = require("aws-sdk");
const S3 = new AWS.S3();
const { v4: uuidv4 } = require("uuid");
const getUrl = async (params) => {
return await new Promise((resolve, reject) => {
S3.getSignedUrl("putObject", params, (err, url) => {
if (err) {
reject(err);
} else {
resolve({
statusCode: 200,
url,
});
}
});
});
};
exports.handler = async (event, context) => {
const id = uuidv4();
const { userId } = event?.queryStringParameters;
const params = {
Bucket: process.env.INVOICE_BUCKET,
Key: `${userId}/${id}.csv`,
ContentType: `text/csv`,
ACL: "public-read",
};
try {
const { url } = await getUrl(params);
return handleRes({ message: `Successfully generated url`, url, key: `${id}.csv`, publicUrl: `https://yourBucket.s3.eu-west-1.amazonaws.com/${userId}/${id}.csv` }, 200);
} catch (e) {
console.error(e);
return handleRes({ message: "failed" }, 400);
}
};
Front end
$(function () {
$("#theForm").on("submit", sendFile);
});
function sendFile(e) {
e.preventDefault();
var urlPresigned;
var publicUrl;
var key;
$.ajax({
type: "GET",
url: `https://yourId.execute-api.eu-west-1.amazonaws.com/Prod/file-upload-to-bucket?userId=${userId}`,
success: function (resp) {
urlPresigned = resp.url;
publicUrl = resp.publicUrl;
key = resp.key;
var theFormFile = $("#theFile").get()[0].files[0];
$.ajax({
type: "PUT",
url: urlPresigned,
contentType: "text/csv", // Put meme type
processData: false,
// the actual file is sent raw
data: theFormFile,
success: function () {
// File uploaed
},
error: function (err) {
console.log(err);
},
});
},
});
}

Zipping multiple PDFs and downloading the zip file?

So as the description says: This is my code
var zip = new JSZip();
var urls = ["https://www.link.ca/documents/PDF/Quarters.pdf",
"https://www.link.ca/documents/PDF/Mills.pdf",
"https://www.link.ca/documents/PDF/Stop.pdf"
];
var count = 0;
var zipFilename = "Check_This_Out.zip";
urls.forEach(function (url) {
debugger;
var filename = "filename";
console.log(url);
JSZipUtils.getBinaryContent(url, function (err, data) {
if (err) {
throw err; // or handle the error
}
zip.file(url, data, {
binary: true
});
count++;
if (count == urls.length) {
zip.generateAsync({
type: "blob"
})
.then(function (blob) {
saveAs(blob, zipFilename);
});
}
});
});
The problem I'm facing is that when I unzip it, it creates a folder structure like the following:
C:\Users\samuser\Downloads\https_\www.link.ca\documents\PDF
My issue/question is how do I fix it so that when I open the Zip file, I should see the three documents I uploaded.

If someone had the same issue, this is how I resolved it:
var filename = url.replace(/.*\//g, "");
zip.file(filename, data, { binary: true, createFolders: true });

Blank images and pdfs downloaded from Dropbox

I have a problem when downloading files from my dropbox.
While using the type 'text/csv' I can download and view txt files.
Chaning the type to 'image/jpeg' or 'application/pdf' and download the filetype gives me blank file.
Am I on the right track here or is there another way this should be done?
main.service.ts
downloadFile(id) {
const headers = new Headers();
headers.append('Authorization', 'Bearer ' + this.accessToken);
const path = `{"path": "${id}"}`;
headers.append('Dropbox-API-Arg', path);
return this.http.post('https://content.dropboxapi.com/2/files/download',
null, { headers: headers });
}
main.component.ts
downloadFileBlob(data: any, name) {
const blob = new Blob([data], { type: 'image/jpeg' });
const url = window.URL.createObjectURL(blob);
window.open(url);
}
saveFile(id, name) {
this.dropbox.downloadFile(id).subscribe((data: any) => {
this.downloadFileBlob(data._body, name); });
}

Turns out I was going at this the wrong way.
Dropbox github has an example of using sharingGetSharedLinkFile, which works about the same as filesDownload.
Replace sharingGetSharedLinkFile with filesDownload and provide a file path instead of the URL.
Something like this:
function downloadFile() {
var ACCESS_TOKEN = (<HTMLInputElement> document.getElementById('access-
token')).value;
var SHARED_LINK = (<HTMLInputElement> document.getElementById('shared-
link')).value;
var dbx = new Dropbox.Dropbox({ accessToken: ACCESS_TOKEN });
dbx.filesDownload({path: SHARED_LINK})
.then(function(data) {
var downloadUrl = URL.createObjectURL((<any> data).fileBlob);
var downloadButton = document.createElement('a');
downloadButton.setAttribute('href', downloadUrl);
downloadButton.setAttribute('download', data.name);
downloadButton.setAttribute('class', 'button');
downloadButton.innerText = 'Download: ' + data.name;
document.getElementById('results').appendChild(downloadButton);
});
}

AJAX not uploading images to backend service

Working on a requirement to upload images to AWS instance. UI and service is separated and connects via REST. Service is in nodejs. from UI we are making a ajax call to backend service to upload the images to AWS.
The problem:
When I upload the images via POSTMAN request, I can see that response as uploaded with files properly uploaded in AWS.
Whereas when I upload images via AJAX call, I get no response in browser, and also the images are not uploaded in aws.
Below is the piece of code in ajax:
var formData = new FormData();
formData.append('image', $('#tx_file_programa')[0]);
$.ajax({
method: 'POST',
type: "POST",
url: 'http://10.0.0.95:9999/photo/1',
contentType: false,
processData: false,
async: false,
cache: false,
beforeSend: function (xhr) {
xhr.setRequestHeader('Authorization', 'Bearer ' + access_token );
},
data: formData,
success: function (data) {
console.log('response from server is : ', data);
}
//dataType: 'json'
});
This is the backend service.
server.post('/photo/:count', function (req, res) {
if (req.getContentType() == 'multipart/form-data') {
var form = new formidable.IncomingForm(),
files = [], fields = [];
var result = [];
var noOfFiles = req.params.count;
var count = 0;
console.log('noOfFiles', noOfFiles);
form.on('field', function(field, value) {
fields.push([field, value]);
console.log(fields);
})
form.on('progress', function(bytesReceived, bytesExpected) {
console.log('err');
});
form.on('error', function(err) {
console.log('err',err);
});
form.on('aborted', function() {
console.log('aborted', arguments);
});
new Promise(function(resolve, reject) {
var result = [];
form.onPart = function (part) {
var data = null;
const params = {
Bucket: 'xxxxx',
Key: uuidv4() + part.filename,
ACL: 'public-read'
};
var upload = s3Stream.upload(params);
upload.on('error', function (error) {
console.log('errr', error);
});
upload.on('part', function (details) {
console.log('part', details);
});
upload.on('uploaded', function (details) {
let extension = details.Location.split('.');
if(['JPG', 'PNG'].indexOf(extension[extension.length - 1].toUpperCase()) > -1) {
var ext = extension[extension.length - 1];
count++;
result.push(details.Location);
if(count == noOfFiles) {
resolve(result);
}
}
});
part.pipe(upload);
}
}).then(function(result){
console.log('end', result);
res.writeHead(200, {'content-type': 'text/plain'});
res.end('received files:\n\n ' + util.inspect(result));
})
form.parse(req, function (err, fields, files) {
})
return;
} else {
BadRequestResponse(res, "Invalid request type!");
}
})

#user3336194, Can you check with this, this is working thins
var appIconFormData = null
$(":file").change(function () {
var file = this.files[0], name = file.name, size = file.size, type = file.type;
var imageType = new Array("image/png", "image/jpeg", "image/gif", "image/bmp");
if (jQuery.inArray(type, imageType) == -1) {
return false;
} else {
appIconFormData = new FormData();
appIconFormData.append('appimage', $('input[type=file]')[0].files[0]);
}
});
$.ajax({
url: 'your/api/destination/url',
type: 'POST',
data: appIconFormData,
cache: false,
contentType: false,
processData: false,
success: function (data) {
console.log(data)
},
error: function (e) {
}
});

I think the way you are sending formdata is not correct.
Try these 2 ways:
You can give your whole form to FormData() for processing
var form = $('form')[0]; // You need to use standard javascript object here
var formData = new FormData(form);
or specify exact data for FormData()
var formData = new FormData();
// Attach file
formData.append('image', $('input[type=file]')[0].files[0]);

Can open blob returned by XMLHTTPRequest, but can't upload to Azure

I am able to upload a file to my vendors API, and the vendor responds with a .png file as binary data. I am able to write this out to a blob in the browser, but I can't get it to upload in Azure blob storage. I also tried uploading it to a Web directory using fs.writefile but that produces a corrupt/non-bitmap image.
Ideally, I would like to upload my blob directly into Azure, but when I try it gives me the following error:
TypeError: must start with number, buffer, array or string
If I need to upload the blob to a Web directory and use Azure's createBlockBlobFromLocalFile, I would be more than happy to, but my attempts have failed thus far.
Here is my XMLHTTPRequest that opens the image in the browser that is returned after I post my file:
var form = document.forms.namedItem("fileinfo");
form.addEventListener('submit', function (ev) {
var oData = new FormData(form);
var xhr = new XMLHttpRequest();
xhr.responseType = "arraybuffer";
xhr.open("POST", "http://myvendorsapi/Upload", true);
xhr.onload = function (oEvent) {
if (xhr.status == 200) {
var blob = new Blob([xhr.response], { type: "image/png" });
var objectUrl = URL.createObjectURL(blob);
window.open(objectUrl);
console.log(blob);
var containerName = boxContainerName;
var filename = 'Texture_0.png';
$http.post('/postAdvanced', { containerName: containerName, filename: filename, file: blob }).success(function (data) {
//console.log(data);
console.log("success!");
}, function (err) {
//console.log(err);
});
} else {
oOutput.innerHTML = "Error " + xhr.status + " occurred when trying to upload your file.<br \/>";
}
};
xhr.send(oData);
ev.preventDefault();
}, false);
Here is my Node backend for the /postAdvanced call:
app.post('/postAdvanced', function (req, res, next) {
var containerName = req.body.containerName;
var filename = req.body.filename;
var file = req.body.file;
if (!Buffer.isBuffer(file)) {
// Convert 'file' to a binary buffer
}
var options = { contentType: 'image/png' };
blobSvc.createBlockBlobFromText(containerName, filename, file, function (error, result, response) {
if (!error) {
res.send(result);
} else {
console.log(error);
}
});
})
If someone can't help me with uploading directly to Azure, if I can get how to upload this blob to a directory, I can get it into Azure via createBlockBlobFromLocalFile

I have solved the issue. I needed to base64 encode the data on the client side before passing it to node to decode to a file. I needed to use XMLHTTPRequest to get binary data properly, as jQuery AJAX appears to have an issue with returning (see here: http://www.henryalgus.com/reading-binary-files-using-jquery-ajax/).
Here is my front end:
var form = document.forms.namedItem("fileinfo");
form.addEventListener('submit', function (ev) {
var oData = new FormData(form);
var xhr = new XMLHttpRequest();
xhr.responseType = "arraybuffer";
xhr.open("POST", "http://vendorapi.net/Upload", true);
xhr.onload = function (oEvent) {
if (xhr.status == 200) {
var blob = new Blob([xhr.response], { type: "image/png" });
//var objectUrl = URL.createObjectURL(blob);
//window.open(objectUrl);
console.log(blob);
var blobToBase64 = function(blob, cb) {
var reader = new FileReader();
reader.onload = function() {
var dataUrl = reader.result;
var base64 = dataUrl.split(',')[1];
cb(base64);
};
reader.readAsDataURL(blob);
};
blobToBase64(blob, function(base64){ // encode
var update = {'blob': base64};
var containerName = boxContainerName;
var filename = 'Texture_0.png';
$http.post('/postAdvancedTest', { containerName: containerName, filename: filename, file: base64}).success(function (data) {
//console.log(data);
console.log("success!");
// Clear previous 3D render
$('#webGL-container').empty();
// Generated new 3D render
$scope.generate3D();
}, function (err) {
//console.log(err);
});
})
} else {
oOutput.innerHTML = "Error " + xhr.status + " occurred when trying to upload your file.<br \/>";
}
};
xhr.send(oData);
ev.preventDefault();
}, false);
Node Backend:
app.post('/postAdvancedTest', function (req, res) {
var containerName = req.body.containerName
var filename = req.body.filename;
var file = req.body.file;
var buf = new Buffer(file, 'base64'); // decode
var tmpBasePath = 'upload/'; //this folder is to save files download from vendor URL, and should be created in the root directory previously.
var tmpFolder = tmpBasePath + containerName + '/';
// Create unique temp directory to store files
mkdirp(tmpFolder, function (err) {
if (err) console.error(err)
else console.log('Directory Created')
});
// This is the location of download files, e.g. 'upload/Texture_0.png'
var tmpFileSavedLocation = tmpFolder + filename;
fs.writeFile(tmpFileSavedLocation, buf, function (err) {
if (err) {
console.log("err", err);
} else {
//return res.json({ 'status': 'success' });
blobSvc.createBlockBlobFromLocalFile(containerName, filename, tmpFileSavedLocation, function (error, result, response) {
if (!error) {
console.log("Uploaded" + result);
res.send(containerName);
}
else {
console.log(error);
}
});
}
})
})