class

M3U8::KeyItem

Inherits M3U8::Encryptable / M3U8::Concern / Reference / Object

KeyItem represents a set of EXT-X-KEY attributes used for specifying the encryption parameters of Media Segments in an HLS playlist.

In HLS, as defined in RFC 8216, Section 4.3.2.4, the EXT-X-KEY tag specifies how Media Segments are encrypted. It includes attributes such as METHOD, URI, IV, KEYFORMAT, and KEYFORMATVERSIONS.

Example of a key tag:

#EXT-X-KEY:METHOD=AES-128,URI="http://test.key",IV=D512BBF,KEYFORMAT="identity",KEYFORMATVERSIONS="1/3"

This class combines the functionality provided by the Concern and Encryptable modules to parse and format these encryption key attributes.

Class methods

parse(text)

Parses a text line representing an EXT-X-KEY tag and returns a new KeyItem.

The method extracts the attribute list from the tag line, converts the keys using Encryptable.convert_key, and initializes a new instance.

Example:

text = %(#EXT-X-KEY:METHOD=AES-128,URI="http://test.key",IV=D512BBF,KEYFORMAT="identity",KEYFORMATVERSIONS="1/3")
KeyItem.parse(text)
# => #<M3U8::KeyItem:0x7f5ceff07a80
      @iv="D512BBF",
      @key_format="identity",
      @key_format_versions="1/3",
      @method="AES-128",
      @uri="http://test.key">

Source

Instance methods

to_s

Returns the string representation of the EXT-X-KEY tag.

It prefixes the formatted key attributes with #EXT-X-KEY:.

Example:

options = {
  method:              "AES-128",
  uri:                 "http://test.key",
  iv:                  "D512BBF",
  key_format:          "identity",
  key_format_versions: "1/3",
}
KeyItem.new(options).to_s
# => "#EXT-X-KEY:METHOD=AES-128,URI=\"http://test.key\",IV=D512BBF,KEYFORMAT=\"identity\",KEYFORMATVERSIONS=\"1/3\""

Source