TagEngine API documentation
rackio.TagEngine
()Current Value Table Engine class for Tag thread-safe based repository.
This class is intended hold in memory tag based values and observers for those required tags, it is implemented as a singleton so each sub-thread within the Rackio application can access tags in a thread-safe mechanism.
Usage:
>>> from rackio.engine import CVTEngine
>>> tag_egine = CVTEngine()
>>> tag_engine.write_tag("TAG1", 40.43)
>>> value = tag_engine.read_tag("TAG1")
>>> print(value)
40.43
set_tag
(self, name, _type, units='')Sets a new value for a defined tag, in thread-safe mechanism.
Parameters:
- name (str): Tag name.
- _type (float, int, bool): Tag value ("int", "float", "bool")
- units (str): Engineering units.
Usage:
>>> tag_engine.set_tag("speed", "float", "km/h")
tag_defined
(self, name)Checks if a tag name is already defined.
Parameters:
- name (str): Tag name.
write_tag
(self, name, value)Writes a new value for a defined tag, in thread-safe mechanism.
Parameters:
- name (str): Tag name.
- value (float, int, bool): Tag value ("int", "float", "bool")
read_tag
(self, name)Returns a tag value defined by name, in thread-safe mechanism.
Parameters:
- name (str): Tag name.
set_tags
(self, tags)Sets new values for a defined list of tags, in thread-safe mechanism.
Parameters:
- tags (list): List of tag name, type and units.
set_group
(self, group, tags)Sets new tags group, which can be retrieved by group name.
Parameters:
- group (str): Group name.
- tags (list): List of defined tag names.
get_group
(self, group)Returns the tag list of the a defined group.
Parameters:
- group (str): Group name.
get_groups
(self)Returns a list of the group names defined.
get_tags
(self)Returns a list of the tag names defined.