What is token-types?
The token-types npm package provides a collection of token parsers for binary data types, facilitating the reading and interpretation of various data types from binary streams. This is particularly useful in applications dealing with multimedia files, where metadata and content need to be extracted or interpreted from binary formats.
What are token-types's main functionalities?
Reading integer values
This feature allows the reading of unsigned 32-bit integers from a buffer in little-endian format. It is useful for parsing low-level binary data structures.
const Token = require('token-types');
const uint32Token = Token.UINT32_LE;
const buffer = Buffer.from([0x01, 0x00, 0x00, 0x00]);
const value = uint32Token.get(buffer, 0);
console.log(value); // Outputs: 1
Reading string values
This feature enables the extraction of ASCII strings from binary data. It supports specifying the length of the string and the encoding, making it versatile for reading text data embedded in binary streams.
const Token = require('token-types');
const stringToken = new Token.StringType(5, 'ascii');
const buffer = Buffer.from('hello');
const value = stringToken.get(buffer, 0);
console.log(value); // Outputs: 'hello'
Other packages similar to token-types
binary-parser
binary-parser offers functionality to build a schema for parsing binary data, which is somewhat similar to token-types. However, binary-parser is more comprehensive in defining complex parsing schemas, making it suitable for applications that require detailed and structured binary data interpretation.
A primitive token library used to read from, and to write a node Buffer
.
Tokens
node-strtok
supports a wide variety of numerical tokens out of the box:
UINT8
UINT16_BE
, UINT16_LE
UINT24_BE
, UINT24_LE
UINT32_BE
, UINT32_LE
INT8
INT16_BE
, INT16_LE
INT24_BE
, INT24_LE
INT32_BE
, INT32_LE
One might notice that there is no support for 64-bit tokens, since JavaScript
seems to limit value size to less than 2^64. Rather than wrapping up an
additional math library to handle this, I wanted to stick with JavaScript
primitives. Maybe this will change later if this becomes important.