rosbridge_library.capability module

class rosbridge_library.capability.Capability(protocol)

Bases: object

Handles the operation-specific logic of a rosbridge message.

May define one or more opcodes to handle, for example ‘publish’ or ‘call_service’

Each connected client receives its own capability instance, which are managed by the client’s own protocol instance.

Protocol.send() is available to send messages back to the client.

basic_type_check(msg, types_info)

Perform basic typechecking on fields in msg.

Parameters:

• msg – A message, deserialized into a dictionary

• types_info –

  A list of tuples (mandatory, fieldname, fieldtype) where

  • mandatory - boolean, is the field mandatory

  • fieldname - the name of the field in the message

  • fieldtypes - the expected python type of the field or list of types

Raises:

• MissingArgumentException – If a field is mandatory but not present in the message

• InvalidArgumentException – If a field is present but not of the type specified by fieldtype

finish()

Notify this capability that the client is finished.

Tells the capability that it’s time to free up resources.

handle_message(message)

Handle an incoming message.

Called by the protocol after having already checked the message op code.

Parameters:

message – The incoming message, deserialized into a dictionary