PDF Files cause `fromStream` to never finish

Using 16.5.3, I’m seeing an issue where an await’ed call to fromStream with a stream of a PDF file never actually resolves

e.g.:

const fileType = await FileType.fromStream(stream);

I haven’t yet been able to test the 17.x release series due other blocking dependencies.

It seems that removing the await from line 592 of node_modules\file-type\core.js causes the function to return properly; and suggests a reference to https://github.com/Borewit/strtok3/issues/551

i.e. this “works”:

if (checkString('%PDF')) {
	await tokenizer.ignore(1350);
	const maxBufferSize = 10 * 1024 * 1024;
	const buffer = Buffer.alloc(Math.min(maxBufferSize, tokenizer.fileInfo.size));
	tokenizer.readBuffer(buffer, {mayBeLess: true});

and this doesn’t:

if (checkString('%PDF')) {
	await tokenizer.ignore(1350);
	const maxBufferSize = 10 * 1024 * 1024;
	const buffer = Buffer.alloc(Math.min(maxBufferSize, tokenizer.fileInfo.size));
	await tokenizer.readBuffer(buffer, {mayBeLess: true});

[crossan007]

@Borewit thanks for the tips.

I think we can close this issue

[Borewit]

fileTypeStream(), in v16 this was stream(), is probably the closest thing to work around your issue. But it comes at a price, it a has a limited sample size preventing the read to much at the cost of some file type determination.