# caproto.server.PvpropertyStringRO¶

class caproto.server.PvpropertyStringRO(*, pvname: str, group: caproto.server.server.PVGroup, pvspec: caproto.server.server.PVSpec, doc: Optional[str] = None, record: Optional[Union[str, Type[T_RecordFields]]] = None, logger: Optional[logging.Logger] = None, **kwargs)[source]

Read-only STRING data for pvproperty (up to 40 chars).

Methods

 auth_read(hostname, username, data_type, *) Get DBR data and native data, converted to a specific type auth_write(hostname, username, data, …[, …]) Data write hook for clients. calculate_length(value) Calculate the number of elements given a value check_access(host, user) This always returns AccessRights.READ|AccessRights.WRITE. get_field(field) Get a field by name. is_compatible_array(value) Check if the provided value is a compatible array. post_state_change(state, new_value) This is called by the server when it exits its StateUpdateContext. pre_state_change(state, new_value) This is called by the server when it enters its StateUpdateContext. preprocess_value(value) Pre-process values destined for verify_value and write publish(flags) Publish data to appropriate queues matching the SubscriptionSpec. read(data_type) The top-level read method, with a specific requested data type. subscribe(queue, sub_spec, sub) Subscribe a queue for the given subscription specification. unsubscribe(queue, sub_spec) Unsubscribe a queue for the given subscription specification. update_fields(value) This is a hook to update field instance data. verify_value(value) The top-level dbr-facing “write” method. write(value, *[, flags]) Write data from native Python types. write_from_dbr(*args[, flags]) Write data from a provided DBR data type. write_metadata([publish, units, precision, …]) Write metadata, optionally publishing information to clients.

Attributes

 alarm The ChannelAlarm associated with this data data_type default_value epics_timestamp EPICS timestamp as (seconds, nanoseconds) since EPICS epoch. length The number of elements (length) of the current value long_string_max_length The maximum number of elements (length) of the current value max_length The maximum number of elements (length) this channel can hold severity Alarm severity status Alarm status timestamp UNIX timestamp in seconds. value Read-only access to value data