inception.streams.multipart
Creates and parses multipart form streams.
installation
Use the following command to install the library from npm:
npm install inception.streams.multipart
usage
The library exposes 2 main classes:
MultipartStreamer: A Readable stream used to create multipart contentMultipartParser: A Writable stream used to parse a multipart stream
streaming multipart content
The following code show how to create a new multipart stream that can be piped into an outgoing HTTP request.
const MultipartStreamer = require('inception.streams.multipart').MultipartStreamer;
const req = getAnInstanceOfHttpClientRequestSomehow();
const myJsonObject = { foo: 'bar' };
const myStream = node.fs.createReadStream('/etc/motd');
const streamer = new MultipartStreamer();
.addFieldPart({ value: 'fieldValue', name: 'fieldName' })
.addObjectPart({ value: myJsonObject })
.addFilePart({ value: '/etc/hosts', contentType: 'text/plain' })
.addStreamPart({ value: myStream, contentType: 'text/html' });
req.headers['content-type'] = `multipart/form-data; boundary=${streamer.boundary}`;
streamer.pipe(req);
parsing multipart content
The following code show how to parse an incoming multipart stream.
const MultipartParser = require('inception.streams.multipart').MultipartParser;
function handleRequest(req, res) {
const parser = new MultipartParser({ contentType: req.headers['content-type']});
req.pipe(parser)
.on('part', (part) => {
switch(part.type) {
case 'field':
res.write(`name: ${part.name}, value: ${part.value}`);
break;
case 'object':
res.write(JSON.stringify(part.value));
break;
case 'stream':
res.write(`name: ${part.name}, contentType: ${part.contentType}`);
part.pipe(node.fs.createWriteStream(`/var/tmp/${part.filename}`));
}
res.write(`Part: ${part}`);
})
.on('finish', () => res.end());
}
Alternately, one can use the .parse() helper method.
const Multipart = require('inception.streams.multipart');
function handleRequest(req, res) {
Multipart.parse(req)
.on('part', (part) => {
switch(part.type) {
case 'field':
res.write(`name: ${part.name}, value: ${part.value}`);
break;
case 'object':
res.write(JSON.stringify(part.value));
break;
case 'stream':
res.write(`name: ${part.name}, contentType: ${part.contentType}`);
part.pipe(node.fs.createWriteStream(`/var/tmp/${part.filename}`));
}
res.write(`Part: ${part}`);
})
.on('finish', () => res.end());
}
contact
All feedback/suggestions/criticisms can be directed to Anand Suresh