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Node Js Meme generation error: File does not exist

Total nodejs newbie here. I am using meme-maker package to generate meme. However I want to create meme with image from url
var fileName = 'https://imgflip.com/s/meme/Futurama-Fry.jpg';
var memeMaker = require('meme-maker')
var options = {
image: fileName, // Required
outfile: 'meme.png', // Required
topText: 'top', // Required
bottomText: 'bottom', // Optional
}
memeMaker(options, function(err) {
if(err) throw new Error(err)
console.log('Image saved: ')
});
However I get error: Error: File does not exist: https://imgflip.com/s/meme/Futurama-Fry.jpg
How to read file from url and make meme?

If you go read the documentation of meme-maker you will see that it only supports local images and not URL's.
You will need to download the image first then use the local address. Go have a look at request

That library does not look like it supports URLs. The image param presumably takes a file path on the local system. If you want to use the URL to make a meme, you will have to:
Download that image from the URL using AJAX or something similar, store it to a file on the disk and get it's local path.
Pass the local file path of the file to the library
Get the generated meme path (and enable download if needed) and do clean up like deleting the old image, for example

Cannot Save Images from URL in Nativescript/Javascript with imageSource module

Context
I'm trying to download a users' Facebook profile picture to the local storage so that I can display it without having to remake the call to Facebook.
Code
I'm using the module image-source to download the image, and the module file-system to access the device's local storage.
Most of the code is referencing the Nativescript image-source documentation page.
var imageSource = require("image-source");
var fs = require("file-system");
exports.theFunction = function(args){
//...
var img = imageSource.fromFile("http://graph.facebook.com/"+user.id+"/picture?type=large");
var folder = fs.knownFolders.documents();
var path = fs.path.join(folder.path, "profilePic.jpg");
console.log(path);
var saved = img.saveToFile(path, enums.ImageFormat.jpg);
appSettings.setString("imgLocal",path);
console.log("Image Saved Successfully");
//...
}
Output
/data/user/0/com.foo.bar/files/profilePic.jpg
I never see the "Image Saved Successfully" message output to console and I have no way of verifying if the image has been stored in the filesystem using the Emulator (I'm developing for Android without a device).
I have also tried wrapping the save event in an if tag, assuming that the output of saveToFile() is a boolean:
if(img.saveToFile(path, enums.ImageFormat.jpg)) console.log("success");
else console.log("failure");
...however this also outputs nothing.
Question
How can I save the image from the URL to the device's local storage?
References
Nativescript
image-source on Nativescript docs
ImageSource on Nativescript API docs

I think main trouble here is in that line, cause ImageSource works only with local files, not urls:
var img = imageSource.fromFile("http://graph.facebook.com/"+user.id+"/picture?type=large");
You should download image, not set source from url. About downloading image you can read here:
https://docs.nativescript.org/cookbook/ui/image-cache
Or try something like this and save it than somehow:
var image = new ImageModule.Image();
image.src = "https://www.google.com/images/errors/logo_sm_2.png";
But about this I'm not quite sure. I've never used nativescript and just looked through the docs.

Saving file with JavaScript File API results wrong encoding

I have a problem (or may be two) with saving files using HTML5 File API.
A files comes from the server as a byte array and I need to save it. I tried several ways described on SO:
creating blob and opening it in a new tab
creating a hidden anchor tag with "data:" in href attribute
using FileSaver.js
All approaches allow to save the file but with breaking it by changing the encoding to UTF-8, while the file (in current test case) is in ANSI. And it seems that I have to problems: at the server side and at the client side.
Server side:
Server side is ASP.NET Web API 2 app, which controller sends the file using HttpResponseMessage with StreamContent. The ContentType is correct and corresponds with actual file type.
But as can be seen on the screenshot below server's answer (data.length) is less then actual file size calculated at upload (file.size). Also here could be seen that HTML5 File object has yet another size (f.size).
If I add CharSet with value "ANSI" to server's response message's ContentType property, file data will be the same as it was uploaded, but on saving result file still has wrong size and become broken:
Client side:
I tried to set charset using the JS File options, but it didn't help. As could be found here and here Eli Grey, the author of FileUplaod.js says that
The encoding/charset in the type is just metadata for the browser, not an encoding directive.
which means, if I understood it right, that it is impossible to change the encoding of the file.
Issue result: at the end I can successfully download broken files which are unable to open.
So I have two questions:
How can I save file "as is" using File API. At present time I cannot use simple way with direct link and 'download' attribute because of serverside check for access_token in request header. May be this is the "bottle neck" of the problem?
How can I avoid setting CharSet at server side and also send byte array "as is"? While this problem could be hacked in some way I guess it's more critical. For example, while "ANSI" charset solves the problem with the current file, WinMerge shows that it's encoding is Cyrillic 'Windows-1251' and also can any other.
P.S. the issue is related to all file types (extensions) except *.txt.
Update
Server side code:
public HttpResponseMessage DownloadAttachment(Guid fileId)
{
var stream = GetFileStream(fileId);
var message = new HttpResponseMessage(HttpStatusCode.OK);
message.Content = new StreamContent(stream);
message.Content.Headers.ContentLength = file.Size;
message.Content.Headers.ContentType = new MediaTypeHeaderValue(file.ContentType)
{
// without this charset files sent with bigger size
// than they are as shown on image 1
CharSet = "ANSI"
};
message.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = file.FileName + file.Extension,
Size = file.Size
};
return message;
}
Client side code (TypeScript):
/*
* Handler for click event on download <a> tag
*/
private downloadFile(file: Models.File) {
var self = this;
this.$service.downloadAttachment(this.entityId, file.fileId).then(
// on success
function (data, status, headers, config) {
var fileName = file.fileName + file.extension;
var clientFile = new File([data], fileName);
// here's the issue ---^
saveAs(clientFile, fileName);
},
// on fail
function (error) {
self.alertError(error);
});
}
My code is almost the same as in answers on related questions on SO: instead of setting direct link in 'a' tag, I handle click on it and download file content via XHR (in my case using Angularjs $http service). Getting the file content I create a Blob object (in my case I use File class that derives from Blob) and then try to save it using FileSaver.js. I also tried approach with encoded URL to Blob in href attribute, but it only opens a new tab with a file broken the same way. I found that the problem is in Blob class - calling it's constructor with 'normal' file data I get an instance with 'wrong' size as could be seen on first two screenshots. So, as I understand, my problem not in the way I try to save my file, but in the way I create it - File API

Image not showing using chrome filesystem toURL

I have the following code to write an image into the filesystem, and read it back for display. Prior to trying out the filesystem API, I loaded the whole base64 image into the src attribute and the image displayed fine. Problem is the images can be large so if you add a few 5MB images, you run out of memory. So I thought I'd just write them to the tmp storage and only pass the URL into the src attribute.
Trouble is, nothing gets displayed.
Initially I thought it might be something wrong with the URL, but then I went into the filesystem directory, found the image it was referring to and physically replaced it with the real binary image and renamed it to the same as the replaced image. This worked fine and the image is displayed correctly, so the URL looks good.
The only conclusion I can come to is that the writing of the image is somehow wrong - particularly the point where the blob is created. I've looked through the blob API and can't see anything that I may have missed, however I'm obviously doing something wrong because it seems to be working for everyone else.
As an aside, I also tried to store the image in IndexedDB and use the createObjectURL to display the image - again, although the URL looks correct, nothing is displayed on the screen. Hence the attempt at the filesystem API. The blob creation is identical in both cases, with the same data.
The source data is a base64 encoded string as I mentioned. Yes, I did also try to store the raw base64 data in the blob (with and without the prefix) and that didn't work either.
Other info - chrome version 28, on linux Ubuntu
//strip the base64 `enter code here`stuff ...
var regex = /^data.+;base64,/;
if (regex.test(imgobj)) { //its base64
imgobj = imgobj.replace(regex,"");
//imgobj = B64.decode(imgobj);
imgobj = window.atob(imgobj);
} else {
console.log("it's already :", typeof imgobj);
}
// store the object into the tmp space
window.requestFileSystem(window.TEMPORARY, 10*1024*1024, function(fs) {
// check if the file already exists
fs.root.getFile(imagename, {create: false}, function(fileEntry) {
console.log("File exists: ", fileEntry);
callback(fileEntry.toURL(), fileEntry.name);
//
}, function (e) { //file doesn't exist
fs.root.getFile(imagename, {create: true}, function (fe) {
console.log("file is: ", fe);
fe.createWriter(function(fw){
fw.onwriteend = function(e) {
console.log("write complete: ", e);
console.log("size of file: ", e.total)
callback(fe.toURL(), fe.name);
};
fw.onerror = function(e) {
console.log("Write failed: ", e.toString());
};
var data = new Blob([imgobj], {type: "image/png"});
fw.write(data);
}, fsErrorHandler);
}, fsErrorHandler);
});
// now create a file
}, fsErrorHandler);
Output from the callback is:
<img class="imgx" src="filesystem:file:///temporary/closed-padlock.png" width="270px" height="270px" id="img1" data-imgname="closed-padlock.png">
I'm at a bit of a standstill unless someone can provide some guidance...
UPDATE
I ran a test to encode and decode the base64 image with both the B64encoder/decoder and atob/btoa -
console.log(imgobj); // this is the original base64 file from the canvas.toDataURL function
/* B64 is broken*/
B64imgobjdecode = B64.decode(imgobj);
B64imgobjencode = B64.encode(B64imgobjdecode);
console.log(B64imgobjencode);
/* atob and btoa decodes and encodes correctly*/
atobimgobj = window.atob(imgobj);
btoaimgobj = window.btoa(atobimgobj);
console.log(btoaimgobj);
The results show that the btoa/atob functions work correctly but the B64 does not - probably because the original encoding didn't use the B64.encode function...
The resulting file in filesystem TEMPORARY, I ran through an online base64 encoder for comparison and the results are totally different. So the question is - while in the filesystem temp storage, is the image supposed to be an exact image, or is it padded with 'something' which only the filesystem API understands? Remember I put the original PNG in the file system directory and the image displayed correctly, which tends to indicate that the meta-data about the image (eg. the filename) is held elsewhere...
Can someone who has a working implementation of this confirm if the images are stored as images in the filesystem, or are padded with additional meta-data?

So to answer my own question - the core problem was in the base64 encoding/decoding - I've since then changed this to use things like ajax and responseTypes like arraybuffer and blob and things have started working.
To answer the last part of the question, this is what I've found - in the filesystem tmp storage, yes the file is supposed to be an exact binary copy - verified this in chrome and phonegap.

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