How to stream response after knowing the Content-Type?

[smoliji]

What would you like to discuss?

How to use got.stream to stream a file response to writable stream, after I have information about the file type - defined in Content-Type header from the response?

I short:

got.stream(imageUrl)
   .on('response', async response => {
        const ext = mime.getExtension(response.headers['content-type']!);
        const outFile = createWriteStream(`${fileName}.${ext}`);
        pipeline(
            response,
            outFile
        );
    })

I have prepared an MWE here, where I do this task with the request library as well as with got.

But when using got, the Node.js process just exists with code = 0 without any error or warnings, and the out file is just a preview and has only 33.7KB (compared to 12MB original image). Only way I've got this working was by adding on('data' handler for the got.stream, but I think this would break the backpressure for the pipeline.

Not sure whether this is a bug or intended.

• Node.js version: v10.16.0
• OS & version: Deepin 15.11

Checklist

• I have read the documentation.

[szmarczak]

Duplicate of #223

[smoliji]

Thanks, totally missed that one!

Just for completion, this seems like the correct way to do this and to fix the "stuck issue", adding resume() resolves it, as proposed in #223 (comment)

got.stream(imageUrl)
   .on('response', async response => {
        const ext = mime.getExtension(response.headers['content-type']!);
        const outFile = createWriteStream(`${fileName}.${ext}`);
        pipeline(
            response,
            outFile
        );
    })
    .resume()

[flaushi]

For others: in @smoliji's code, the third parameter, a callback, was missing. But the solution works! Thanks!