Base64

A small base64 module to encode or decode base64 text.

Note: It is recommended to enable caching for large chunks of texts for up to x2 optimization.

Example usage

local base64 = require(".base64")

local str = "This will be encoded"

-- is: "VGhpcyB3aWxsIGJlIGVuY29kZWQ="
local encoded = base64.encode(str)

-- is: "This will be encoded"
local decoded = base64.decode(encoded)

assert(decoded == str)

Module functions

encode()

This function encodes the provided string using the default encoder table. The encoder can be customized and a cache is available for larger chunks of data.

• Parameters:
  • str: {string} The string to encode
  • encoder: {table} Optional custom encoding table
  • usecache: {boolean} Optional cache for large strings (turned off by default)
• Returns: Base64 encoded string

Examples

-- prints: "SGVsbG8gd29ybGQ="
print(base64.encode("Hello world"))

-- customize encoder and allow caching
base64.encode(
  "Hello world",
  base64.makeencoder(nil, "-"),
  true
)

decode()

This function decodes the provided base64 encoded string using the default decoder table. The decoder can be customized and a cache is also available here.

• Parameters:
  • str: {string} The base64 encoded string to decode
  • decoder: {table} Optional custom decoding table
  • usecache: {boolean} Optional cache for large strings (turned off by default)
• Returns: Decoded string

Examples

-- prints: "Hello world"
print(base64.decode("SGVsbG8gd29ybGQ="))

-- customize decoder and allow caching
base64.decode(
  "SGVsbG8gd29ybGQ=",
  base64.makedecoder(nil, "-"),
  true
)

makeencoder()

Allows creating a new encoder table to customize the encode() function's result.

• Parameters:
  • s62: {string} Optional custom char for 62 (+ by default)
  • s63: {string} Optional custom char for 63 (/ by default)
  • spad: {string} Optional custom padding char (= by default)
• Returns: Custom encoder table

Examples

-- create custom encoder
local encoder = base64.makeencoder(nil, nil, "~")

-- prints "SGVsbG8gd29ybGQ~" instead of "SGVsbG8gd29ybGQ="
print(base64.encode("Hello world", encoder))

makedecoder()

Allows creating a new decoder table to be able to decode custom-encoded base64 strings.

• Parameters:
  • s62: {string} Optional custom char for 62 (+ by default)
  • s63: {string} Optional custom char for 63 (/ by default)
  • spad: {string} Optional custom padding char (= by default)
• Returns: Custom decoder table

Examples

local encoder = base64.makeencoder(nil, nil, "~")
local decoder = base64.makedecoder(nil, nil, "~")

-- "SGVsbG8gd29ybGQ~"
local encoded = base64.encode("Hello world", encoder)

-- prints "Hello world"
print(base64.decode(encoded, decoder))