Description
A very fast streaming multipart parser for node.js.
Benchmarks can be found here.
Requirements
Install
npm install dicer
Examples
- Parse an HTTP form upload
var inspect = require('util').inspect,
http = require('http');
var Dicer = require('dicer');
var RE_BOUNDARY = /^multipart\/.+?(?:; boundary=(?:(?:"(.+)")|(?:([^\s]+))))$/i,
HTML = new Buffer('<html><head></head><body>\
<form method="POST" enctype="multipart/form-data">\
<input type="text" name="textfield"><br />\
<input type="file" name="filefield"><br />\
<input type="submit">\
</form>\
</body></html>'),
PORT = 8080;
http.createServer(function(req, res) {
var m;
if (req.method === 'POST'
&& req.headers['content-type']
&& (m = RE_BOUNDARY.exec(req.headers['content-type']))) {
var d = new Dicer({ boundary: m[1] || m[2] });
d.on('part', function(p) {
console.log('New part!');
p.on('header', function(header) {
for (var h in header) {
console.log('Part header: k: ' + inspect(h)
+ ', v: ' + inspect(header[h]));
}
});
p.on('data', function(data) {
console.log('Part data: ' + inspect(data.toString()));
});
p.on('end', function() {
console.log('End of part\n');
});
});
d.on('finish', function() {
console.log('End of parts');
res.writeHead(200);
res.end('Form submission successful!');
});
req.pipe(d);
} else if (req.method === 'GET' && req.url === '/') {
res.writeHead(200);
res.end(HTML);
} else {
res.writeHead(404);
res.end();
}
}).listen(PORT, function() {
console.log('Listening for requests on port ' + PORT);
});
API
Dicer is a WritableStream
Dicer (special) events
-
end() - Emitted when all parts have been parsed.
-
part(< PartStream >stream) - Emitted when a new part has been found.
-
preamble(< PartStream >stream) - Emitted for preamble if you should happen to need it (can usually be ignored).
-
trailer(< Buffer >data) - Emitted when trailing data was found after the terminating boundary (as with the preamble, this can usually be ignored too).
Dicer methods
-
(constructor)(< object >config) - Creates and returns a new Dicer instance with the following valid config
settings:
-
boundary - string - This is the boundary used to detect the beginning of a new part.
-
headerFirst - boolean - If true, preamble header parsing will be performed first.
-
maxHeaderPairs - integer - The maximum number of header key=>value pairs to parse Default: 2000 (same as node's http).
-
setBoundary(< string >boundary) - (void) - Sets the boundary to use for parsing and performs some initialization needed for parsing. You should only need to use this if you set headerFirst
to true in the constructor and are parsing the boundary from the preamble header.
PartStream is a ReadableStream
PartStream (special) events
- header(< object >header) - An object containing the header for this particular part. Each property value is an array of one or more string values.