I've refactored a simple utility to use promises. It fetches a pdf from the web and saves it to disk. It should then open the file in a pdf viewer once saved to disk. The file appears on disk and is valid, the shell command opens the OSX Preview application, but a dialog pops up complaining that the file is empty.
What's the best way to execute the shell function once the filestream has been written to disk?
// download a pdf and save to disk
// open pdf in osx preview for example
download_pdf()
.then(function(path) {
shell.exec('open ' + path).code !== 0);
});
function download_pdf() {
const path = '/local/some.pdf';
const url = 'http://somewebsite/some.pdf';
const stream = request(url);
const write = stream.pipe(fs.createWriteStream(path))
return streamToPromise(stream);
}
function streamToPromise(stream) {
return new Promise(function(resolve, reject) {
// resolve with location of saved file
stream.on("end", resolve(stream.dests[0].path));
stream.on("error", reject);
})
}
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