core/homeassistant/helpers/template.py

444 lines
14 KiB
Python

"""Template helper methods for rendering strings with HA data."""
from datetime import datetime
import json
import logging
import re
import jinja2
from jinja2.sandbox import ImmutableSandboxedEnvironment
from homeassistant.const import (
STATE_UNKNOWN, ATTR_LATITUDE, ATTR_LONGITUDE, MATCH_ALL)
from homeassistant.core import State
from homeassistant.exceptions import TemplateError
from homeassistant.helpers import location as loc_helper
from homeassistant.loader import get_component
from homeassistant.util import convert, dt as dt_util, location as loc_util
from homeassistant.util.async import run_callback_threadsafe
_LOGGER = logging.getLogger(__name__)
_SENTINEL = object()
DATE_STR_FORMAT = "%Y-%m-%d %H:%M:%S"
_RE_NONE_ENTITIES = re.compile(r"distance\(|closest\(", re.I | re.M)
_RE_GET_ENTITIES = re.compile(
r"(?:(?:states\.|(?:is_state|is_state_attr|states)\(.)([\w]+\.[\w]+))",
re.I | re.M
)
def attach(hass, obj):
"""Recursively attach hass to all template instances in list and dict."""
if isinstance(obj, list):
for child in obj:
attach(hass, child)
elif isinstance(obj, dict):
for child in obj.values():
attach(hass, child)
elif isinstance(obj, Template):
obj.hass = hass
def extract_entities(template):
"""Extract all entities for state_changed listener from template string."""
if template is None or _RE_NONE_ENTITIES.search(template):
return MATCH_ALL
extraction = _RE_GET_ENTITIES.findall(template)
if len(extraction) > 0:
return list(set(extraction))
return MATCH_ALL
class Template(object):
"""Class to hold a template and manage caching and rendering."""
def __init__(self, template, hass=None):
"""Instantiate a Template."""
if not isinstance(template, str):
raise TypeError('Expected template to be a string')
self.template = template
self._compiled_code = None
self._compiled = None
self.hass = hass
def ensure_valid(self):
"""Return if template is valid."""
if self._compiled_code is not None:
return
try:
self._compiled_code = ENV.compile(self.template)
except jinja2.exceptions.TemplateSyntaxError as err:
raise TemplateError(err)
def extract_entities(self):
"""Extract all entities for state_changed listener."""
return extract_entities(self.template)
def render(self, variables=None, **kwargs):
"""Render given template."""
if variables is not None:
kwargs.update(variables)
return run_callback_threadsafe(
self.hass.loop, self.async_render, kwargs).result()
def async_render(self, variables=None, **kwargs):
"""Render given template.
This method must be run in the event loop.
"""
self._ensure_compiled()
if variables is not None:
kwargs.update(variables)
try:
return self._compiled.render(kwargs).strip()
except jinja2.TemplateError as err:
raise TemplateError(err)
def render_with_possible_json_value(self, value, error_value=_SENTINEL):
"""Render template with value exposed.
If valid JSON will expose value_json too.
"""
return run_callback_threadsafe(
self.hass.loop, self.async_render_with_possible_json_value, value,
error_value).result()
# pylint: disable=invalid-name
def async_render_with_possible_json_value(self, value,
error_value=_SENTINEL):
"""Render template with value exposed.
If valid JSON will expose value_json too.
This method must be run in the event loop.
"""
self._ensure_compiled()
variables = {
'value': value
}
try:
variables['value_json'] = json.loads(value)
except ValueError:
pass
try:
return self._compiled.render(variables).strip()
except jinja2.TemplateError as ex:
_LOGGER.error('Error parsing value: %s (value: %s, template: %s)',
ex, value, self.template)
return value if error_value is _SENTINEL else error_value
def _ensure_compiled(self):
"""Bind a template to a specific hass instance."""
if self._compiled is not None:
return
self.ensure_valid()
assert self.hass is not None, 'hass variable not set on template'
location_methods = LocationMethods(self.hass)
global_vars = ENV.make_globals({
'closest': location_methods.closest,
'distance': location_methods.distance,
'is_state': self.hass.states.is_state,
'is_state_attr': self.hass.states.is_state_attr,
'states': AllStates(self.hass),
})
self._compiled = jinja2.Template.from_code(
ENV, self._compiled_code, global_vars, None)
return self._compiled
def __eq__(self, other):
"""Compare template with another."""
return (self.__class__ == other.__class__ and
self.template == other.template and
self.hass == other.hass)
class AllStates(object):
"""Class to expose all HA states as attributes."""
def __init__(self, hass):
"""Initialize all states."""
self._hass = hass
def __getattr__(self, name):
"""Return the domain state."""
return DomainStates(self._hass, name)
def __iter__(self):
"""Return all states."""
return iter(sorted(self._hass.states.async_all(),
key=lambda state: state.entity_id))
def __call__(self, entity_id):
"""Return the states."""
state = self._hass.states.get(entity_id)
return STATE_UNKNOWN if state is None else state.state
class DomainStates(object):
"""Class to expose a specific HA domain as attributes."""
def __init__(self, hass, domain):
"""Initialize the domain states."""
self._hass = hass
self._domain = domain
def __getattr__(self, name):
"""Return the states."""
return self._hass.states.get('{}.{}'.format(self._domain, name))
def __iter__(self):
"""Return the iteration over all the states."""
return iter(sorted(
(state for state in self._hass.states.async_all()
if state.domain == self._domain),
key=lambda state: state.entity_id))
class LocationMethods(object):
"""Class to expose distance helpers to templates."""
def __init__(self, hass):
"""Initialize the distance helpers."""
self._hass = hass
def closest(self, *args):
"""Find closest entity.
Closest to home:
closest(states)
closest(states.device_tracker)
closest('group.children')
closest(states.group.children)
Closest to a point:
closest(23.456, 23.456, 'group.children')
closest('zone.school', 'group.children')
closest(states.zone.school, 'group.children')
"""
if len(args) == 1:
latitude = self._hass.config.latitude
longitude = self._hass.config.longitude
entities = args[0]
elif len(args) == 2:
point_state = self._resolve_state(args[0])
if point_state is None:
_LOGGER.warning('Closest:Unable to find state %s', args[0])
return None
elif not loc_helper.has_location(point_state):
_LOGGER.warning(
'Closest:State does not contain valid location: %s',
point_state)
return None
latitude = point_state.attributes.get(ATTR_LATITUDE)
longitude = point_state.attributes.get(ATTR_LONGITUDE)
entities = args[1]
else:
latitude = convert(args[0], float)
longitude = convert(args[1], float)
if latitude is None or longitude is None:
_LOGGER.warning(
'Closest:Received invalid coordinates: %s, %s',
args[0], args[1])
return None
entities = args[2]
if isinstance(entities, (AllStates, DomainStates)):
states = list(entities)
else:
if isinstance(entities, State):
gr_entity_id = entities.entity_id
else:
gr_entity_id = str(entities)
group = get_component('group')
states = [self._hass.states.get(entity_id) for entity_id
in group.expand_entity_ids(self._hass, [gr_entity_id])]
return loc_helper.closest(latitude, longitude, states)
def distance(self, *args):
"""Calculate distance.
Will calculate distance from home to a point or between points.
Points can be passed in using state objects or lat/lng coordinates.
"""
locations = []
to_process = list(args)
while to_process:
value = to_process.pop(0)
if isinstance(value, State):
latitude = value.attributes.get(ATTR_LATITUDE)
longitude = value.attributes.get(ATTR_LONGITUDE)
if latitude is None or longitude is None:
_LOGGER.warning(
'Distance:State does not contains a location: %s',
value)
return None
else:
# We expect this and next value to be lat&lng
if not to_process:
_LOGGER.warning(
'Distance:Expected latitude and longitude, got %s',
value)
return None
value_2 = to_process.pop(0)
latitude = convert(value, float)
longitude = convert(value_2, float)
if latitude is None or longitude is None:
_LOGGER.warning('Distance:Unable to process latitude and '
'longitude: %s, %s', value, value_2)
return None
locations.append((latitude, longitude))
if len(locations) == 1:
return self._hass.config.distance(*locations[0])
return self._hass.config.units.length(
loc_util.distance(*locations[0] + locations[1]), 'm')
def _resolve_state(self, entity_id_or_state):
"""Return state or entity_id if given."""
if isinstance(entity_id_or_state, State):
return entity_id_or_state
elif isinstance(entity_id_or_state, str):
return self._hass.states.get(entity_id_or_state)
return None
def forgiving_round(value, precision=0):
"""Rounding filter that accepts strings."""
try:
value = round(float(value), precision)
return int(value) if precision == 0 else value
except (ValueError, TypeError):
# If value can't be converted to float
return value
def multiply(value, amount):
"""Filter to convert value to float and multiply it."""
try:
return float(value) * amount
except (ValueError, TypeError):
# If value can't be converted to float
return value
def timestamp_custom(value, date_format=DATE_STR_FORMAT, local=True):
"""Filter to convert given timestamp to format."""
try:
date = dt_util.utc_from_timestamp(value)
if local:
date = dt_util.as_local(date)
return date.strftime(date_format)
except (ValueError, TypeError):
# If timestamp can't be converted
return value
def timestamp_local(value):
"""Filter to convert given timestamp to local date/time."""
try:
return dt_util.as_local(
dt_util.utc_from_timestamp(value)).strftime(DATE_STR_FORMAT)
except (ValueError, TypeError):
# If timestamp can't be converted
return value
def timestamp_utc(value):
"""Filter to convert given timestamp to UTC date/time."""
try:
return dt_util.utc_from_timestamp(value).strftime(DATE_STR_FORMAT)
except (ValueError, TypeError):
# If timestamp can't be converted
return value
def forgiving_as_timestamp(value):
"""Try to convert value to timestamp."""
try:
return dt_util.as_timestamp(value)
except (ValueError, TypeError):
return None
def strptime(string, fmt):
"""Parse a time string to datetime."""
try:
return datetime.strptime(string, fmt)
except (ValueError, AttributeError):
return string
def fail_when_undefined(value):
"""Filter to force a failure when the value is undefined."""
if isinstance(value, jinja2.Undefined):
value()
return value
def forgiving_float(value):
"""Try to convert value to a float."""
try:
return float(value)
except (ValueError, TypeError):
return value
class TemplateEnvironment(ImmutableSandboxedEnvironment):
"""The Home Assistant template environment."""
def is_safe_callable(self, obj):
"""Test if callback is safe."""
return isinstance(obj, AllStates) or super().is_safe_callable(obj)
ENV = TemplateEnvironment()
ENV.filters['round'] = forgiving_round
ENV.filters['multiply'] = multiply
ENV.filters['timestamp_custom'] = timestamp_custom
ENV.filters['timestamp_local'] = timestamp_local
ENV.filters['timestamp_utc'] = timestamp_utc
ENV.filters['is_defined'] = fail_when_undefined
ENV.filters['max'] = max
ENV.filters['min'] = min
ENV.globals['float'] = forgiving_float
ENV.globals['now'] = dt_util.now
ENV.globals['utcnow'] = dt_util.utcnow
ENV.globals['as_timestamp'] = forgiving_as_timestamp
ENV.globals['relative_time'] = dt_util.get_age
ENV.globals['strptime'] = strptime