#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You 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.
#
"""
Access and manage name&value preferences, persisted in a local JSON file.
"""
import os
import json
THIS_DIR = os.path.abspath(os.path.dirname(__file__))
FILE = os.path.join(THIS_DIR, ".release-settings.json")
prefs = {}
if os.path.exists(FILE):
with open(FILE, "r") as prefs_fp:
prefs = json.load(prefs_fp)
if len(prefs) > 0:
print(f"Using preferences from: {FILE}")
def save():
"""
Save preferences dictionary.
"""
print(f"Saving preferences to {FILE}")
with open(FILE, "w") as prefs_fp:
json.dump(prefs, prefs_fp)
def set(name, val):
"""
Store and persist a preference.
"""
prefs[name] = val
save()
def unset(name):
"""
Removes a preference.
"""
del prefs[name]
save()
def get(name, supplier):
"""
Retrieve preference if it already exists or delegate
to the given value supplier and store the result.
"""
val = prefs.get(name)
if not val:
val = supplier()
set(name, val)
else:
print(f"Assuming: {name} = {val}")
return val
def once(name, action):
"""
Performs the given action if and only if no record of it
having been executed before exists in the preferences dictionary.
"""
def run_action():
action()
return True
get(f"did_{name}", run_action)
def as_json():
"""
Export all saved preferences in JSON format.
"""
json.dumps(prefs, indent=2)