Adafruit_IO_Python/Adafruit_IO/model.py
Tony DiCola 9900d508f5 Major update:
- Refactored REST client to use requests library for Python 3 compatibility.
- Added docstrings to all public methods & classes.
- Fleshed out CRUD APIs for data, feed, group.
- Wrote full suite of integration tests to verify changes.
- Updated setup.py to bump version to 0.9 & depend on requests and paho-mqtt modules.
- Updated and tested code to work with both Python 2 and 3.
- Broke out errors into separate file, and added explicit data model classes.
- General cleanup and preparation for public release.
2015-02-01 12:22:03 -08:00

117 lines
4.5 KiB
Python

# Copyright (c) 2014 Adafruit Industries
# Author: Tony DiCola
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
from collections import namedtuple
# Handle python 2 and 3 (where map functions like itertools.imap)
try:
from itertools import imap as map
except ImportError:
# Ignore import error on python 3 since map already behaves as expected.
pass
# List of fields/properties that are present on a data object from IO.
DATA_FIELDS = [ 'created_epoch',
'created_at',
'updated_at',
'value',
'completed_at',
'feed_id',
'expiration',
'position',
'id' ]
STREAM_FIELDS = [ 'completed_at',
'created_at',
'id',
'value' ]
FEED_FIELDS = [ 'last_value_at',
'name',
'stream',
'created_at',
'updated_at',
'unit_type',
'mode',
'key',
'unit_symbol',
'fixed',
'last_value',
'id' ]
GROUP_FIELDS = [ 'description',
'source_keys',
'id',
'source',
'key',
'feeds',
'properties',
'name' ]
# These are very simple data model classes that are based on namedtuple. This is
# to keep the classes simple and prevent any confusion around updating data
# locally and forgetting to send those updates back up to the IO service (since
# tuples are immutable you can't change them!). Depending on how people use the
# client it might be prudent to revisit this decision and consider making these
# full fledged classes that are mutable.
Data = namedtuple('Data', DATA_FIELDS)
Stream = namedtuple('Stream', STREAM_FIELDS)
Feed = namedtuple('Feed', FEED_FIELDS)
Group = namedtuple('Group', GROUP_FIELDS)
# Magic incantation to make all parameters to the initializers optional with a
# default value of None.
Data.__new__.__defaults__ = tuple(None for x in DATA_FIELDS)
Stream.__new__.__defaults__ = tuple(None for x in STREAM_FIELDS)
Feed.__new__.__defaults__ = tuple(None for x in FEED_FIELDS)
Group.__new__.__defaults__ = tuple(None for x in GROUP_FIELDS)
# Define methods to convert from dicts to the data types.
def _from_dict(cls, data):
# Convert dict to call to class initializer (to work with the data types
# base on namedtuple). However be very careful to preserve forwards
# compatibility by ignoring any attributes in the dict which are unknown
# by the data type.
params = {x: data.get(x, None) for x in cls._fields}
return cls(**params)
def _feed_from_dict(cls, data):
params = {x: data.get(x, None) for x in cls._fields}
# Parse the stream if provided and generate a stream instance.
params['stream'] = Stream.from_dict(data.get('stream', {}))
return cls(**params)
def _group_from_dict(cls, data):
params = {x: data.get(x, None) for x in cls._fields}
# Parse the feeds if they're provided and generate feed instances.
params['feeds'] = tuple(map(Feed.from_dict, data.get('feeds', [])))
return cls(**params)
# Now add the from_dict class methods defined above to the data types.
Data.from_dict = classmethod(_from_dict)
Stream.from_dict = classmethod(_from_dict)
Feed.from_dict = classmethod(_feed_from_dict)
Group.from_dict = classmethod(_group_from_dict)