http-message-parser

HTTP message parser in JavaScript.

Demo

https://lab.miguelmota.com/http-message-parser

Install

npm install http-message-parser

Documentation

The function takes in a string or Buffer (recommended).

The result message body and multipart bodies will always return back as a Buffer in Node.js in order to retain it's original encoding, for example when it parses a response containing binary audio data it won't stringify the binary data. The library avoids stringifying the body by performing offset slices on the input buffer.

Use the buffer module if dealing with binary data in the browser.

Getting started

Here's a simple example

multipart_example.txt

HTTP/1.1 200 OK
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary=frontier

This is a message with multiple parts in MIME format.
--frontier
Content-Type: text/plain

This is the body of the message.
--frontier
Content-Type: application/octet-stream
Content-Transfer-Encoding: base64

PGh0bWw+CiAgPGhlYWQ+CiAgPC9oZWFkPgogIDxib2R5PgogICAgPHA+VGhpcyBpcyB0aGUg
Ym9keSBvZiB0aGUgbWVzc2FnZS48L3A+CiAgPC9ib2R5Pgo8L2h0bWw+Cg==
--frontier

const httpMessageParser = require('http-message-parser');
const fs = require('fs');
 
fs.readFile('multipart_example.txt', 'binary', (error, messageBuffer) => {
  if (error) {
    return console.error(error);
  }
 
  const parsedMessage = httpMessageParser(messageBuffer);
 
  console.log(parsedMessage);
  //
  {
    httpVersion: 1.1,
    statusCode: 200,
    statusMessage: 'OK',
    method: null,
    url: null,
    headers: {
      'MIME-Version': '1.0'
      'Content-Type': 'multipart/mixed; boundary=frontier'
    },
    body: <Buffer>, // "This is a message with multiple parts in MIME format."
    boundary: 'frontier',
    multipart: [
      {
        headers: {
          'Content-Type': 'text/plain'
        },
        body: <Buffer> // "This is the body of the message."
      },
      {
        headers: {
          'Content-Type': 'application/octet-stream'
          'Content-Transfer-Encoding': 'base64'
        },
        body: <Buffer> // "PGh0bWw+CiAgPGhlYWQ+CiAgPC9oZWFkPgogIDxib2R5Pgog..."
      }
    ]
  }
});

Command Line

Parsing input file:

$ http-message-parser multipart_example.txt

Piping input file:

$ cat multipart_example.txt | http-message-parser

Piping input file and only picking specified mulipart body:

$ cat multipart_example.txt | http-message-parser --pick=multipart[0].body

Piping cURL response and picking specified header:

$ curl -sD - http://www.example.com/ | http-message-parser --pick=headers[Last-Modified]

Test

npm test

License

MIT