Message API reference

The message API allows any object within pulseaudio to register a message
handler. A message handler is a function that can be called by clients using
PA_COMMAND_SEND_OBJECT_MESSAGE. A message consists at least of an object path
and a message command, both specified as strings. Additional parameters can
be specified using a single string in JSON format, but are not mandatory.

The message handler returns an error number as defined in def.h and also returns
a string in the "response" variable. Non-empty response will be in JSON format.

The reference further down lists available messages, their parameters
and return values.

Reference:

Object path: /core
Message: list-handlers
Parameters: None
Return value: JSON array of handler description objects
    [{"name":"Handler name","description":"Description"} ...]

Object path: /card/bluez_card.XX_XX_XX_XX_XX_XX/bluez
Message: list-codecs
Parameters: None
Return value: JSON array of codec description objects
    [{"name":"codec1","description":"Codec 1"} ...]

Object path: /card/bluez_card.XX_XX_XX_XX_XX_XX/bluez
Message: get-codec
Parameters: None
Return value: "codec name"

Object path: /card/bluez_card.XX_XX_XX_XX_XX_XX/bluez
Message: switch-codec
Parameters: "codec name"
Return value: none

Description: Set if card profile selection should be sticky instead of being automated
Object path: /card/<card_name>
Message: set-profile-sticky
Parameters: JSON "true" or "false"
Return value: none

Description: Get if card profile selection should be sticky instead of being automated
Object path: /card/<card_name>
Message: get-profile-sticky
Parameters: None
Return value: JSON "true" or "false"

Object path: /cards/<card_name>
Message: set-jack-detection
Parameters: {"port_name|all":true|false}
Return value: None

Object path: /cards/<card_name>
Message: get-jack-detection
Parameters: "port_name|all"
Return value: {"port_name":true|false}
If "all" is specified, the returned object looks different:
{"Card name":"card_name", "Detection states":{"port_name":true|false, ...}}

Object path: /cards/<card_name>
Message: set-port-state
Parameters: {"port_name|all":0|1|2}
Return value: None
0=unknown, 1=no, 2=yes

Object path: /cards/<card_name>
Message: get-port-state
Parameters: "port_name|all"
Return value: {"port_name":0|1|2}
If "all" is specified, the returned object looks different:
{"Card name":"card_name", "Port states":{"port_name":0|1|2, ...}}