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Node Node-v12

HTTP Parser

This library parses HTTP protocol for requests and responses. It was created to replace http_parser.c since calling C++ functions from JS is really slow in V8. However, it is now primarily useful in having a more flexible/tolerant HTTP parser when dealing with legacy services that do not meet the strict HTTP parsing rules Node's parser follows.

This is packaged as a standalone npm module. To use in node, monkeypatch HTTPParser.

// Monkey patch before you require http for the first time.
process.binding('http_parser').HTTPParser = require('http-parser-js').HTTPParser;

var http = require('http');
// ...


Simply run npm test. The tests are copied from node and mscedex/io.js, with some modifcations.


This should now be usable in any node application, it now supports (nearly) everything http_parser.c does while still being tolerant with corrupted headers, and other kinds of malformed data.

Node versions

http-parser-js should work via monkey-patching on Node v6-v11, and v13-14.

Node v12.x renamed the internal http parser, and did not expose it for monkey-patching, so to be able to monkey-patch on Node v12, you must run node --http-parser=legacy file.js to opt in to the old, monkey-patchable http_parser binding.

Standalone usage

While this module is intended to be used as a replacement for the internal Node.js parser, it can be used as a standalone parser. The standalone-example.js demonstrates how to use the somewhat awkward API (coming from compatibility with the Node.js internals) to parse HTTP from raw Buffers.


MIT. See