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.

If you pass a reference to unbound method for read, write or is_allowed method (e.g. DeviceClass.read_function or self.__class__.read_function), during execution the corresponding bound method (self.read_function) will be used.

Parameters:

  • attr (server.attribute or 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 (if attr is of type server.attribute, then use the fget field in the attr object instead)

  • w_meth (callable) – the write method to be called on a write request (if attr is writable) (if attr is of type server.attribute, then use the fset field in the attr object instead)

  • is_allo_meth (callable) – the method that is called to check if it is possible to access the attribute or not (if attr is of type server.attribute, then use the fisallowed field in the attr object instead)

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, source=None)

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

  • *args – Arguments to format a message string.

  • source (Callable) – Function that will be inspected for filename and lineno in the log message.

New in version 9.4.2: added source parameter

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, source=None)

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

  • *args – Arguments to format a message string.

  • source (Callable) – Function that will be inspected for filename and lineno in the log message.

New in version 9.4.2: added source parameter

fatal_stream(self, msg, *args, source=None)

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

  • *args – Arguments to format a message string.

  • source (Callable) – Function that will be inspected for filename and lineno in the log message.

New in version 9.4.2: added source parameter

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_config(self, attr_names) → list[DeviceAttributeConfig]

Returns the list of AttributeConfig for the requested names

Parameters:

attr_names (list[str]) – sequence of str with attribute names

Returns:

tango.DeviceAttributeConfig for each requested attribute name

Return type:

list[tango.DeviceAttributeConfig]

get_attribute_config_2(self, attr_names) → list[AttributeConfig_2]

Returns the list of AttributeConfig_2 for the requested names

Parameters:

attr_names (list[str]) – sequence of str with attribute names

Returns:

list of tango.AttributeConfig_2 for each requested attribute name

Return type:

list[tango.AttributeConfig_2]

get_attribute_config_3(self, attr_name) → list[AttributeConfig_3]

Returns the list of AttributeConfig_3 for the requested names

Parameters:

attr_names (list[str]) – sequence of str with attribute names

Returns:

list of tango.AttributeConfig_3 for each requested attribute name

Return type:

list[tango.AttributeConfig_3]

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_class(self)

Get device class singleton.

Returns:

the device class singleton (device_class field)

Return type:

DeviceClass

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, source=None)

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

  • *args – Arguments to format a message string.

  • source (Callable) – Function that will be inspected for filename and lineno in the log message.

New in version 9.4.2: added source parameter

init_device(self)

Intialize the device.

init_logger(self) → None

Setups logger for the device. Called automatically when device starts.

is_attribute_polled(self, attr_name) → bool

True if the attribute is polled.

Parameters:

attr_name (str) – attribute name

Returns:

True if the attribute is polled

Return type:

bool

is_command_polled(self, cmd_name) → bool

True if the command is polled.

Parameters:

cmd_name (str) – attribute name

Returns:

True if the command is polled

Return type:

bool

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

poll_attribute(self, attr_name, period) → None

Add an attribute to the list of polled attributes.

Parameters:

  • attr_name (str) – attribute name

  • period (int) – polling period in milliseconds

Returns:

None

Return type:

None

poll_command(self, cmd_name, period) → None

Add a command to the list of polled commands.

Parameters:

  • cmd_name (str) – attribute name

  • period (int) – polling period in milliseconds

Returns:

None

Return type:

None

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.

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.

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)

Push a data ready event for the given attribute name.

The method needs the attribute name and a “counter” which will be passed 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.

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

  • free_it (bool) – free Attr object flag. Default False

  • clean_db (bool) – clean attribute related info in db. Default True

Raises:

DevFailed –

New in version 9.5.0: free_it parameter. clean_db parameter.

remove_command(self, cmd_name, free_it=False, clean_db=True)

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 –

server_init_hook(self)

Hook method.

This method is called once the device server admin device is exported. This allows for instance for the different devices to subscribe to events at server startup on attributes from other devices of the same device server with stateless parameter set to false.

This method can be redefined in sub-classes in case of the default behaviour does not fullfill the needs

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_attribute_config_3(self, new_conf) → None

Sets attribute configuration locally and in the Tango database

Parameters:

new_conf (list[tango.AttributeConfig_3]) – The new attribute(s) configuration. One AttributeConfig structure is needed for each attribute to update

Returns:

None

Return type:

None

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_data_ready_event(self, attr_name, implemented)

Set an implemented flag for the attribute to indicate that the server fires data ready events manually.

Parameters:

  • attr_name (str) – attribute name

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

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.

start_logging(self) → None

Starts logging

stop_logging(self) → None

Stops logging

stop_poll_attribute(self, attr_name) → None

Remove an attribute from the list of polled attributes.

Parameters:

attr_name (str) – attribute name

Returns:

None

Return type:

None

stop_poll_command(self, cmd_name) → None

Remove a command from the list of polled commands.

Parameters:

cmd_name (str) – cmd_name name

Returns:

None

Return type:

None

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, source=None)

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

  • *args – Arguments to format a message string.

  • source (Callable) – Function that will be inspected for filename and lineno in the log message.

New in version 9.4.2: added source parameter

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.