Reputation: 3215
I have a front end Canvas that I transform into a png file that I need to POST to a third party vendor's api. It passes back to node as a base64 file and I decode it, but when I attempt the upload, it gives me the following error:
Problem processing POST request: no Content-Type specified
However, I am clearly specifying the content type in my POST call. My end goal is to upload the file to my vendor's API.
Here are the key front end aspects:
var canvasImage = document.getElementById("c");
var img = canvas.toDataURL({
multiplier: canvasMultiplier
});
var fileTime = Date.now();
var myFileName = $scope.productCode + fileTime;
$scope.filenameForVendor = myFileName;
var filename = $scope.filenameForVendor;
$http.post('/postVendor', { filename: filename, file: img }).success(function (data) {
console.log("Uploaded to Vendor");
Here is the backend POST:
app.post('/postVendor', function (req, res, next) {
var filename = req.body.filename;
var file = req.body.file;
fileBuffer = decodeBase64Image(file);
request({
url: "http://myvendorapi/ws/endpoint",
method: "POST",
headers: {
'contentType': fileBuffer.type
},
body: fileBuffer.data
}, function (error, response, body) {
console.log(response);
});
})
// Decode file for upload
function decodeBase64Image(dataString) {
var matches = dataString.match(/^data:([A-Za-z-+\/]+);base64,(.+)$/),
response = {};
if (matches.length !== 3) {
return new Error('Invalid input string');
}
response.type = matches[1];
response.data = new Buffer(matches[2], 'base64');
return response;
}
I can POST using AJAX on the front end, but because of CORS and the vendor blocking all but server side calls to the endpoints (and they don't have JSONP), I can't use this. They are allowing my IP through for testing purposes so only I can make this work from my machine:
var send = function (blob) {
var fileTime = Date.now();
var myFileName = $scope.productCode + fileTime;
$scope.filenameForVendor = myFileName;
var filename = $scope.filenameForVendor;
var formdata = new FormData();
formdata.append('File1', blob, filename);
$.ajax({
url: 'http://myvendorapi/ws/endpoint',
type: "POST",
data: formdata,
mimeType: "multipart/form-data",
processData: false,
contentType: false,
crossDomain: true,
success: function (result) {
console.log("Upload to Vendor complete!");
// rest of code here/including error close out
}
var bytes = atob(dataURL.split(',')[1])
var arr = new Uint8Array(bytes.length);
for (var i = 0; i < bytes.length; i++) {
arr[i] = bytes.charCodeAt(i);
}
send(new Blob([arr], { type: 'image/png' }));
Update:
I realized that contentType should be 'content-type'. When I did this, it creates an error of no boundary specified as I am trying multipart-form data (which I did all wrong). How can I pass formData to Node for uploading?
Update 2:
Per the advice offered, I tried using multer but am getting an ReferenceError: XMLHttpRequest is not defined.
Client side:
var fileTime = Date.now();
var myFileName = $scope.productCode + fileTime;
$scope.filenameForVendor = myFileName;
var filename = $scope.filenameForVendor;
var formdata = new FormData();
formdata.append('File1', blob, filename);
$http.post('/postVendor', formdata, { transformRequest: angular.identity, headers: { 'Content-Type': undefined } }).success(function (data) {
Server side:
app.post('/postVendor', function (req, res, next) {
var request = new XMLHttpRequest();
request.open("POST", "http://myvendorapi.net/ws/endpoint");
request.send(formData);
})
Upvotes: 1
Views: 270
Reputation: 773
Why do you base64 encode the file?
You can upload raw file to your Node using FormData and you will not have to decode anything.
...
var request = new XMLHttpRequest();
request.open('POST', 'http://node.js/method');
request.send(formData); // vanilla
--- or ---
...
$http.post('http://node.js/method', formData, {
transformRequest: angular.identity,
headers: {'Content-Type': undefined}
}); // angular
Just install request.
...
var request = require('request');
app.post('/method', function (req, res, next) {
// if you just want to push request you don't need to parse anything
req.pipe(request('http://vendor.net')).pipe(res);
}) // express
Upvotes: 1