When the VOD transcoding platform performs HLS common encryption on a video file, it will write the URL used to get the decryption key into the
EXT-X-KEY tag of the M3U8 file. For more information, please see HLS Common Encryption.
An HLS common encryption template contains
definition (unique template ID) and
get_key_url (URL used to get the decryption key) parameters.
Only VOD APIs 2017 are available for management of HLS common encryption templates.