mycroft-core/mycroft/dialog/__init__.py

189 lines
6.9 KiB
Python

# Copyright 2017 Mycroft AI Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
import random
import os
import re
from pathlib import Path
from os.path import join
from mycroft.util import resolve_resource_file
from mycroft.util.format import expand_options
from mycroft.util.log import LOG
__doc__ = """
"""
class MustacheDialogRenderer:
"""
A dialog template renderer based on the mustache templating language.
"""
def __init__(self):
self.templates = {}
self.recent_phrases = []
# TODO magic numbers are bad!
self.max_recent_phrases = 3
# We cycle through lines in .dialog files to keep Mycroft from
# repeating the same phrase over and over. However, if a .dialog
# file only contains a few entries, this can cause it to loop.
#
# This offset will override max_recent_phrases on very short .dialog
# files. With the offset at 2, .dialog files with 3 or more lines will
# be managed to avoid repetition, but .dialog files with only 1 or 2
# lines will be unaffected. Dialog should never get stuck in a loop.
self.loop_prevention_offset = 2
def load_template_file(self, template_name, filename):
"""
Load a template by file name into the templates cache.
Args:
template_name (str): a unique identifier for a group of templates
filename (str): a fully qualified filename of a mustache template.
"""
with open(filename, 'r', encoding='utf8') as f:
for line in f:
template_text = line.strip()
# Skip all lines starting with '#' and all empty lines
if (not template_text.startswith('#') and
template_text != ''):
if template_name not in self.templates:
self.templates[template_name] = []
# convert to standard python format string syntax. From
# double (or more) '{' followed by any number of
# whitespace followed by actual key followed by any number
# of whitespace followed by double (or more) '}'
template_text = re.sub(r'\{\{+\s*(.*?)\s*\}\}+', r'{\1}',
template_text)
self.templates[template_name].append(template_text)
def render(self, template_name, context=None, index=None):
"""
Given a template name, pick a template and render it using the context.
If no matching template exists use template_name as template.
Tries not to let Mycroft say exactly the same thing twice in a row.
Args:
template_name (str): the name of a template group.
context (dict): dictionary representing values to be rendered
index (int): optional, the specific index in the collection of
templates
Returns:
str: the rendered string
"""
context = context or {}
if template_name not in self.templates:
# When not found, return the name itself as the dialog
# This allows things like render("record.not.found") to either
# find a translation file "record.not.found.dialog" or return
# "record not found" literal.
return template_name.replace(".", " ")
# Get the .dialog file's contents, minus any which have been spoken
# recently.
template_functions = self.templates.get(template_name)
if index is None:
template_functions = ([t for t in template_functions
if t not in self.recent_phrases] or
template_functions)
line = random.choice(template_functions)
else:
line = template_functions[index % len(template_functions)]
# Replace {key} in line with matching values from context
line = line.format(**context)
line = random.choice(expand_options(line))
# Here's where we keep track of what we've said recently. Remember,
# this is by line in the .dialog file, not by exact phrase
self.recent_phrases.append(line)
if (len(self.recent_phrases) >
min(self.max_recent_phrases, len(self.templates.get(
template_name)) - self.loop_prevention_offset)):
self.recent_phrases.pop(0)
return line
class DialogLoader:
"""
Loads a collection of dialog files into a renderer implementation.
"""
def __init__(self, renderer_factory=MustacheDialogRenderer):
self.__renderer = renderer_factory()
def load(self, dialog_dir):
"""
Load all dialog files within the specified directory.
Args:
dialog_dir (str): directory that contains dialog files
Returns:
a loaded instance of a dialog renderer
"""
directory = Path(dialog_dir)
if not directory.exists() or not directory.is_dir():
LOG.warning("No dialog files found: {}".format(dialog_dir))
return self.__renderer
for path, _, files in os.walk(str(directory)):
for f in files:
if f.endswith(".dialog"):
self.__renderer.load_template_file(
f.replace('.dialog', ''),
join(path, f))
return self.__renderer
def get(phrase, lang=None, context=None):
"""
Looks up a resource file for the given phrase. If no file
is found, the requested phrase is returned as the string.
This will use the default language for translations.
Args:
phrase (str): resource phrase to retrieve/translate
lang (str): the language to use
context (dict): values to be inserted into the string
Returns:
str: a randomized and/or translated version of the phrase
"""
if not lang:
from mycroft.configuration import Configuration
lang = Configuration.get().get("lang")
filename = "text/" + lang.lower() + "/" + phrase + ".dialog"
template = resolve_resource_file(filename)
if not template:
LOG.debug("Resource file not found: {}".format(filename))
return phrase
stache = MustacheDialogRenderer()
stache.load_template_file("template", template)
if not context:
context = {}
return stache.render("template", context)