Device

DeviceImpl

class tango.LatestDeviceImpl

Latest implementation of the TANGO device base class (alias for Device_5Impl).

It inherits from CORBA classes where all the network layer is implemented.

add_attribute(self, attr, r_meth=None, w_meth=None, is_allo_meth=None)Attr

Add a new attribute to the device attribute list.

Please, note that if you add an attribute to a device at device creation time, this attribute will be added to the device class attribute list. Therefore, all devices belonging to the same class created after this attribute addition will also have this attribute.

Parameters
  • attr (Attr or AttrData) – the new attribute to be added to the list.

  • r_meth (callable) – the read method to be called on a read request

  • w_meth (callable) – the write method to be called on a write request (if attr is writable)

  • is_allo_meth (callable) – the method that is called to check if it is possible to access the attribute or not

Returns

the newly created attribute.

Return type

Attr

Raises

DevFailed

add_command(self, cmd, device_level=True)cmd

Add a new command to the device command list.

Parameters
  • cmd – the new command to be added to the list

  • device_level – Set this flag to true if the command must be added for only this device

Returns

The command to add

Return type

Command

Raises

DevFailed

always_executed_hook(self)

Hook method.

Default method to implement an action necessary on a device before any command is executed. This method can be redefined in sub-classes in case of the default behaviour does not fullfill the needs

Raises

DevFailed – This method does not throw exception but a redefined method can.

append_status(self, status, new_line=False)

Appends a string to the device status.

Parameters
  • status (str) – the string to be appened to the device status

  • new_line (bool) – If true, appends a new line character before the string. Default is False

check_command_exists(self)

Check that a command is supported by the device and does not need input value.

The method throws an exception if the command is not defined or needs an input value.

Parameters

cmd_name (str) – the command name

Raises
  • DevFailed

  • API_IncompatibleCmdArgumentType

  • API_CommandNotFound

New in PyTango 7.1.2

debug_stream(self, msg, *args)

Sends the given message to the tango debug stream.

Since PyTango 7.1.3, the same can be achieved with:

print(msg, file=self.log_debug)
Parameters

msg (str) – the message to be sent to the debug stream

delete_device(self)

Delete the device.

dev_state(self)DevState

Get device state.

Default method to get device state. The behaviour of this method depends on the device state. If the device state is ON or ALARM, it reads the attribute(s) with an alarm level defined, check if the read value is above/below the alarm and eventually change the state to ALARM, return the device state. For all th other device state, this method simply returns the state This method can be redefined in sub-classes in case of the default behaviour does not fullfill the needs.

Returns

the device state

Return type

DevState

Raises

DevFailed – If it is necessary to read attribute(s) and a problem occurs during the reading

dev_status(self)str

Get device status.

Default method to get device status. It returns the contents of the device dev_status field. If the device state is ALARM, alarm messages are added to the device status. This method can be redefined in sub-classes in case of the default behaviour does not fullfill the needs.

Returns

the device status

Return type

str

Raises

DevFailed – If it is necessary to read attribute(s) and a problem occurs during the reading

error_stream(self, msg, *args)

Sends the given message to the tango error stream.

Since PyTango 7.1.3, the same can be achieved with:

print(msg, file=self.log_error)
Parameters

msg (str) – the message to be sent to the error stream

fatal_stream(self, msg, *args)

Sends the given message to the tango fatal stream.

Since PyTango 7.1.3, the same can be achieved with:

print(msg, file=self.log_fatal)
Parameters

msg (str) – the message to be sent to the fatal stream

get_attr_min_poll_period(self)Sequence[str]

Returns the min attribute poll period

Returns

the min attribute poll period

Return type

Sequence[str]

New in PyTango 7.2.0

get_attr_poll_ring_depth(self, attr_name)int

Returns the attribute poll ring depth.

Parameters

attr_name (str) – the attribute name

Returns

the attribute poll ring depth

Return type

int

New in PyTango 7.1.2

get_attribute_poll_period(self, attr_name)int

Returns the attribute polling period (ms) or 0 if the attribute is not polled.

Parameters

attr_name (str) – attribute name

Returns

attribute polling period (ms) or 0 if it is not polled

Return type

int

New in PyTango 8.0.0

get_cmd_min_poll_period(self)Sequence[str]

Returns the min command poll period.

Returns

the min command poll period

Return type

Sequence[str]

New in PyTango 7.2.0

get_cmd_poll_ring_depth(self, cmd_name)int

Returns the command poll ring depth.

Parameters

cmd_name (str) – the command name

Returns

the command poll ring depth

Return type

int

New in PyTango 7.1.2

get_command_poll_period(self, cmd_name)int

Returns the command polling period (ms) or 0 if the command is not polled.

Parameters

cmd_name (str) – command name

Returns

command polling period (ms) or 0 if it is not polled

Return type

int

New in PyTango 8.0.0

get_dev_idl_version(self)int

Returns the IDL version.

Returns

the IDL version

Return type

int

New in PyTango 7.1.2

get_device_attr(self)MultiAttribute

Get device multi attribute object.

Returns

the device’s MultiAttribute object

Return type

MultiAttribute

get_device_properties(self, ds_class=None)

Utility method that fetches all the device properties from the database and converts them into members of this DeviceImpl.

Parameters

ds_class (DeviceClass) – the DeviceClass object. Optional. Default value is None meaning that the corresponding DeviceClass object for this DeviceImpl will be used

Raises

DevFailed

get_exported_flag(self)bool

Returns the state of the exported flag

Returns

the state of the exported flag

Return type

bool

New in PyTango 7.1.2

get_logger(self)Logger

Returns the Logger object for this device

Returns

the Logger object for this device

Return type

Logger

get_min_poll_period(self)int

Returns the min poll period.

Returns

the min poll period

Return type

int

New in PyTango 7.2.0

get_name(self)

Get a COPY of the device name.

Returns

the device name

Return type

str

get_non_auto_polled_attr(self)Sequence[str]

Returns a COPY of the list of non automatic polled attributes

Returns

a COPY of the list of non automatic polled attributes

Return type

Sequence[str]

New in PyTango 7.1.2

get_non_auto_polled_cmd(self)Sequence[str]

Returns a COPY of the list of non automatic polled commands

Returns

a COPY of the list of non automatic polled commands

Return type

Sequence[str]

New in PyTango 7.1.2

get_poll_old_factor(self)int

Returns the poll old factor

Returns

the poll old factor

Return type

int

New in PyTango 7.1.2

get_poll_ring_depth(self)int

Returns the poll ring depth

Returns

the poll ring depth

Return type

int

New in PyTango 7.1.2

get_polled_attr(self)Sequence[str]

Returns a COPY of the list of polled attributes

Returns

a COPY of the list of polled attributes

Return type

Sequence[str]

New in PyTango 7.1.2

get_polled_cmd(self)Sequence[str]

Returns a COPY of the list of polled commands

Returns

a COPY of the list of polled commands

Return type

Sequence[str]

New in PyTango 7.1.2

get_prev_state(self)DevState

Get a COPY of the device’s previous state.

Returns

the device’s previous state

Return type

DevState

get_state(self)DevState

Get a COPY of the device state.

Returns

Current device state

Return type

DevState

get_status(self)str

Get a COPY of the device status.

Returns

the device status

Return type

str

info_stream(self, msg, *args)

Sends the given message to the tango info stream.

Since PyTango 7.1.3, the same can be achieved with:

print(msg, file=self.log_info)
Parameters

msg (str) – the message to be sent to the info stream

init_device(self)

Intialize the device.

is_device_locked(self)bool

Returns if this device is locked by a client.

Returns

True if it is locked or False otherwise

Return type

bool

New in PyTango 7.1.2

is_polled(self)bool

Returns if it is polled

Returns

True if it is polled or False otherwise

Return type

bool

New in PyTango 7.1.2

is_there_subscriber(self, att_name, event_type)bool

Check if there is subscriber(s) listening for the event.

This method returns a boolean set to true if there are some subscriber(s) listening on the event specified by the two method arguments. Be aware that there is some delay (up to 600 sec) between this method returning false and the last subscriber unsubscription or crash…

The device interface change event is not supported by this method.

Parameters
  • att_name (str) – the attribute name

  • event_type (EventType) – the event type

Returns

True if there is at least one listener or False otherwise

Return type

bool

push_archive_event(self, attr_name)
push_archive_event(self, attr_name, except)
push_archive_event(self, attr_name, data, dim_x=1, dim_y=0)
push_archive_event(self, attr_name, str_data, data)
push_archive_event(self, attr_name, data, time_stamp, quality, dim_x=1, dim_y=0)
push_archive_event(self, attr_name, str_data, data, time_stamp, quality)

Push an archive event for the given attribute name.

The event is pushed to the notification daemon.

Parameters
  • attr_name (str) – attribute name

  • data – the data to be sent as attribute event data. Data must be compatible with the attribute type and format. for SPECTRUM and IMAGE attributes, data can be any type of sequence of elements compatible with the attribute type

  • str_data (str) – special variation for DevEncoded data type. In this case ‘data’ must be a str or an object with the buffer interface.

  • except (DevFailed) – Instead of data, you may want to send an exception.

  • dim_x (int) – the attribute x length. Default value is 1

  • dim_y (int) – the attribute y length. Default value is 0

  • time_stamp (double) – the time stamp

  • quality (AttrQuality) – the attribute quality factor

Raises

DevFailed – If the attribute data type is not coherent.

push_att_conf_event(self, attr)

Push an attribute configuration event.

Parameters

attr (Attribute) – the attribute for which the configuration event will be sent.

New in PyTango 7.2.1

push_change_event(self, attr_name)
push_change_event(self, attr_name, except)
push_change_event(self, attr_name, data, dim_x=1, dim_y=0)
push_change_event(self, attr_name, str_data, data)
push_change_event(self, attr_name, data, time_stamp, quality, dim_x=1, dim_y=0)
push_change_event(self, attr_name, str_data, data, time_stamp, quality)

Push a change event for the given attribute name.

The event is pushed to the notification daemon.

Parameters
  • attr_name (str) – attribute name

  • data – the data to be sent as attribute event data. Data must be compatible with the attribute type and format. for SPECTRUM and IMAGE attributes, data can be any type of sequence of elements compatible with the attribute type

  • str_data (str) – special variation for DevEncoded data type. In this case ‘data’ must be a str or an object with the buffer interface.

  • except (DevFailed) – Instead of data, you may want to send an exception.

  • dim_x (int) – the attribute x length. Default value is 1

  • dim_y (int) – the attribute y length. Default value is 0

  • time_stamp (double) – the time stamp

  • quality (AttrQuality) – the attribute quality factor

Raises

DevFailed – If the attribute data type is not coherent.

push_data_ready_event(self, attr_name, counter=0)

Push a data ready event for the given attribute name.

The event is pushed to the notification daemon.

The method needs only the attribue name and an optional “counter” which will be passed unchanged within the event

Parameters
  • attr_name (str) – attribute name

  • counter (int) – the user counter

Raises

DevFailed – If the attribute name is unknown.

push_event(self, attr_name, filt_names, filt_vals)
push_event(self, attr_name, filt_names, filt_vals, data, dim_x=1, dim_y=0)
push_event(self, attr_name, filt_names, filt_vals, str_data, data)
push_event(self, attr_name, filt_names, filt_vals, data, time_stamp, quality, dim_x=1, dim_y=0)
push_event(self, attr_name, filt_names, filt_vals, str_data, data, time_stamp, quality)

Push a user event for the given attribute name.

The event is pushed to the notification daemon.

Parameters
  • attr_name (str) – attribute name

  • filt_names (Sequence[str]) – the filterable fields name

  • filt_vals (Sequence[double]) – the filterable fields value

  • data – the data to be sent as attribute event data. Data must be compatible with the attribute type and format. for SPECTRUM and IMAGE attributes, data can be any type of sequence of elements compatible with the attribute type

  • str_data (str) – special variation for DevEncoded data type. In this case ‘data’ must be a str or an object with the buffer interface.

  • dim_x (int) – the attribute x length. Default value is 1

  • dim_y (int) – the attribute y length. Default value is 0

  • time_stamp (double) – the time stamp

  • quality (AttrQuality) – the attribute quality factor

Raises

DevFailed – If the attribute data type is not coherent.

push_pipe_event(self, blob)

Push an pipe event.

Parameters

blob – the blob which pipe event will be send.

New in PyTango 9.2.2

read_attr_hardware(self, attr_list)

Read the hardware to return attribute value(s).

Default method to implement an action necessary on a device to read the hardware involved in a read attribute CORBA call. This method must be redefined in sub-classes in order to support attribute reading

Parameters

attr_list (Sequence[int]) – list of indices in the device object attribute vector of an attribute to be read.

Raises

DevFailed – This method does not throw exception but a redefined method can.

register_signal(self, signo)

Register a signal.

Register this device as device to be informed when signal signo is sent to to the device server process

Parameters

signo (int) – signal identifier

remove_attribute(self, attr_name)

Remove one attribute from the device attribute list.

Parameters

attr_name (str) – attribute name

Raises

DevFailed

remove_command(self, attr_name)

Remove one command from the device command list.

Parameters
  • cmd_name (str) – command name to be removed from the list

  • free_it (bool) – set to true if the command object must be freed.

  • clean_db – Clean command related information (included polling info if the command is polled) from database.

Raises

DevFailed

set_archive_event(self, attr_name, implemented, detect=True)

Set an implemented flag for the attribute to indicate that the server fires archive events manually, without the polling to be started.

If the detect parameter is set to true, the criteria specified for the archive event are verified and the event is only pushed if they are fullfilled. If detect is set to false the event is fired without any value checking!

Parameters
  • attr_name (str) – attribute name

  • implemented (bool) – True when the server fires change events manually.

  • detect (bool) – Triggers the verification of the change event properties when set to true. Default value is true.

set_change_event(self, attr_name, implemented, detect=True)

Set an implemented flag for the attribute to indicate that the server fires change events manually, without the polling to be started.

If the detect parameter is set to true, the criteria specified for the change event are verified and the event is only pushed if they are fullfilled. If detect is set to false the event is fired without any value checking!

Parameters
  • attr_name (str) – attribute name

  • implemented (bool) – True when the server fires change events manually.

  • detect (bool) – Triggers the verification of the change event properties when set to true. Default value is true.

set_state(self, new_state)

Set device state.

Parameters

new_state (DevState) – the new device state

set_status(self, new_status)

Set device status.

Parameters

new_status (str) – the new device status

signal_handler(self, signo)

Signal handler.

The method executed when the signal arrived in the device server process. This method is defined as virtual and then, can be redefined following device needs.

Parameters

signo (int) – the signal number

Raises

DevFailed – This method does not throw exception but a redefined method can.

stop_polling(self)
stop_polling(self, with_db_upd)

Stop all polling for a device. if the device is polled, call this method before deleting it.

Parameters

with_db_upd (bool) – Is it necessary to update db?

New in PyTango 7.1.2

unregister_signal(self, signo)

Unregister a signal.

Unregister this device as device to be informed when signal signo is sent to to the device server process

Parameters

signo (int) – signal identifier

warn_stream(self, msg, *args)

Sends the given message to the tango warn stream.

Since PyTango 7.1.3, the same can be achieved with:

print(msg, file=self.log_warn)
Parameters

msg (str) – the message to be sent to the warn stream

write_attr_hardware(self)

Write the hardware for attributes.

Default method to implement an action necessary on a device to write the hardware involved in a write attribute. This method must be redefined in sub-classes in order to support writable attribute

Parameters

attr_list (Sequence[int]) – list of indices in the device object attribute vector of an attribute to be written.

Raises

DevFailed – This method does not throw exception but a redefined method can.