Automate System

Introduction

automate.system.System encapsulates the state machine parts into single object. It has already been explained how to use System. Here we will go further into some details.

Groups

In Automate system, it is possible to group objects by putting them to Groups. Grouping helps organizing objects in code level as well as in GUIs (Web User Interface for Automate etc.).

Here is an example:

class MySystem(System):
    class group1(Group):
        sensor1 = UserBoolSensor()
        sensor2 = UserBoolSensor()

    class group2(Group):
        sensor3 = UserBoolSensor()
        sensor4 = UserBoolSensor()

By adding SystemObject to a group, will assign it a tag corresponding to its groups class name. I.e. here, sensor1 and sensor2 will get tag group:group1 and sensor3 and sensor4 will get tag group:group2.

System has single namespace dictionary that contains names of all objects. That implies that objects in different groups may not have same name.

System State Saving and Restoring via Serialization

If System state is desired to be loaded later from periodically auto-saved state dumps, system can be instantiated via load_or_create() as follows:

my_system_instance = MySystem.load_or_create('my_statedump.dmp')

Then system state will be saved periodically (by default, once per 30 minutes) by StatusSaverService, which is automatically loaded service (see Services). If you desire to change interval, you need to explicitly define dump_interval as follows:

status_saver = StatusSaverService(dump_interval=10) # interval in seconds
my_system_instance = MySystem.load_or_create('my_statedump.dmp', services=[status_saver])

SystemObject

Inheritance diagram of automate.system.SystemObject

SystemObject is baseclass for all objects that may be used within System (most importantly, Sensors, Actuators and Programs).

Due to multiple inheritance, many SystemObjects, such as Sensors (AbstractSensor), Actuators (AbstractActuator), and Programs (Program) can act in multiple roles, in addition to their primary role, as follows:

  • Sensors and actuators can always be used also as a program i.e. they may have conditions and action callables defined, because they derive from ProgrammableSystemObject.
  • Both Actuators and Sensors can be used as triggers in Callables and via them in Programs
  • Also plain Programs can be used as a Sensor. Then its activation status (boolean) serves as Sensor status.

Sensors and Programs do not have Actuator properties (i.e. per-program statuses), but Sensor status can still be set/written by a Program, similarly to actuators with slave attribute set to True.

System Class Definition

class automate.system.System(loadstate=None, **traits)[source]
allow_name_referencing = None

Allow referencing objects by their names in Callables. If disabled, you can still refer to objects by names by Object(‘name’)

filename = None

Filename to where to dump the system state

logfile = None

Name of the file where logs are stored

print_level = None

Log level for the handler that writes to stdout

logger = None

Reference to logger instance (read-only)

log_handler = None

Instance to the log handler that writes to stdout

log_format = None

Format string of the log handler that writes to stdout

print_handler = None

Instance to the log handler that writes to logfile (read-only)

logfile_format = None

Format string of the log handler that writes to logfile

log_level = None

Log level of the handler that writes to logfile

default_services = None

Add here services that you want to be added automatically. This is meant to be re-defined in subclass.

services = None

List of services that are loaded in the initialization of the System.

exclude_services = None

List of servicenames that are desired to be avoided (even if normally autoloaded).

namespace = None

System namespace (read-only)

objects_sorted = None

Property giving objects sorted alphabetically (read-only)

sensors = None

Read-only property giving all sensors of the system

actuators = None

Read-only property giving all actuator of the system

programs = None

Read-only property giving all objects that have program features in use

ordinary_programs = None

Read-only property giving all Program objects

worker_autostart = None

Start worker thread automatically after system is initialized

pre_exit_trigger = None

Trigger which is triggered before quiting (used by Services)

all_tags = None

Read-only property that gives list of all object tags

two_phase_queue = None

Enable experimental two-phase queue handling technique (not recommended)

classmethod load_or_create(filename=None, **kwargs)[source]

Load system from a dump, if dump file exists, or create a new system if it does not exist.

save_state()[source]

Save state of the system to a dump file System.filename

cmd_namespace

A read-only property that gives the namespace of the system for evaluating commands.

get_unique_name(obj, name='', name_from_system='')[source]

Give unique name for an Sensor/Program/Actuator object

services_by_name

A property that gives a dictionary that contains services as values and their names as keys.

service_names

A property that gives the names of services as a list

flush()[source]

Flush the worker queue. Usefull in unit tests.

name_to_system_object(name)[source]

Give SystemObject instance corresponding to the name

eval_in_system_namespace(exec_str)[source]

Get Callable for specified string (for GUI-based editing)

register_service_functions(*funcs)[source]

Register function in the system namespace. Called by Services.

register_service(service)[source]

Register service into the system. Called by Services.

request_service(type, id=0)[source]

Used by Sensors/Actuators/other services that need to use other services for their operations.

cleanup()[source]

Clean up before quitting

cmd_exec(cmd)[source]

Execute commands in automate namespace

name = None

Name of the system (shown in WEB UI for example)

worker_thread = None

Reference to the worker thread (read-only)

post_init_trigger = None

Trigger which is triggered after initialization is ready (used by Services)

SystemObjects Class Definition

class automate.systemobject.SystemObject(name='', **traits)[source]

Baseclass for Programs, Sensor, Actuators

callables = []

Names of attributes that accept Callables. If there are custom callables being used, they must be added here. The purpose of this list is that these Callables will be initialized properly. ProgrammableSystemObject introduces 5 basic callables (see also Programs).

get_default_callables()[source]

Get a dictionary of default callables, in form {name:callable}. Re-defined in subclasses.

system = None

Reference to System object

description = None

Description of the object (shown in WEB interface)

tags = None

Tags are used for (for example) grouping objects. See Groups.

name = None

Name property is determined by System namespace. Can be read/written.

hide_in_uml = None

If set to True, current SystemObject is hidden in the UML diagram of WEB interface.

view = ['hide_in_uml']

Attributes that can be edited by user in WEB interface

data_type = ''

The data type name (as string) of the object. This is written in the initialization, and is used by WEB interface Django templates.

editable = False

If editable=True, a quick edit widget will appear in the web interface. Define in subclasses.

object_type

A read-only property that gives the object type as string; sensor, actuator, program, other. Used by WEB interface templates.

logger = None

Python Logger instance for this object. System creates each object its own logger instance.

get_status_display(**kwargs)[source]

Redefine this in subclasses if status can be represented in human-readable way (units etc.)

get_as_datadict()[source]

Get information about this object as a dictionary. Used by WebSocket interface to pass some relevant information to client applications.

setup(*args, **kwargs)[source]

Initialize necessary services etc. here. Define this in subclasses.

setup_system(system, name_from_system='', **kwargs)[source]

Set system attribute and do some initialization. Used by System.

setup_callables()[source]

Setup Callable attributes that belong to this object.

cleanup()[source]

Write here whatever cleanup actions are needed when object is no longer used.