Alexa Smart Home Skill Adapter for Home Assistant

lambda_function.py

"""
Copyright 2019 Jason Hu <awaregit at gmail.com>

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 os
import json
import logging
import urllib3

_debug = bool(os.environ.get('DEBUG'))

_logger = logging.getLogger('HomeAssistant-SmartHome')
_logger.setLevel(logging.DEBUG if _debug else logging.INFO)


def lambda_handler(event, context):
    """Handle incoming Alexa directive."""
    
    _logger.debug('Event: %s', event)

    base_url = os.environ.get('BASE_URL')
    assert base_url is not None, 'Please set BASE_URL environment variable'
    base_url = base_url.strip("/")

    directive = event.get('directive')
    assert directive is not None, 'Malformatted request - missing directive'
    assert directive.get('header', {}).get('payloadVersion') == '3', \
        'Only support payloadVersion == 3'
    
    scope = directive.get('endpoint', {}).get('scope')
    if scope is None:
        # token is in grantee for Linking directive 
        scope = directive.get('payload', {}).get('grantee')
    if scope is None:
        # token is in payload for Discovery directive 
        scope = directive.get('payload', {}).get('scope')
    assert scope is not None, 'Malformatted request - missing endpoint.scope'
    assert scope.get('type') == 'BearerToken', 'Only support BearerToken'

    token = scope.get('token')
    if token is None and _debug:
        token = os.environ.get('LONG_LIVED_ACCESS_TOKEN')  # only for debug purpose
    
    verify_ssl = not bool(os.environ.get('NOT_VERIFY_SSL'))
    
    http = urllib3.PoolManager(
        cert_reqs='CERT_REQUIRED' if verify_ssl else 'CERT_NONE',
        timeout=urllib3.Timeout(connect=2.0, read=10.0)
    )
    
    response = http.request(
        'POST', 
        '{}/api/alexa/smart_home'.format(base_url),
        headers={
            'Authorization': 'Bearer {}'.format(token),
            'Content-Type': 'application/json',
        },
        body=json.dumps(event).encode('utf-8'),
    )
    if response.status >= 400:
        return {
            'event': {
                'payload': {
                    'type': 'INVALID_AUTHORIZATION_CREDENTIAL' 
                            if response.status in (401, 403) else 'INTERNAL_ERROR',
                    'message': response.data.decode("utf-8"),
                }
            }
        }
    _logger.debug('Response: %s', response.data.decode("utf-8"))
    return json.loads(response.data.decode('utf-8'))

I am not quite sure, why this isn't working for my setup. My domain has a CNAME alias pointing to a DynDNS service. Neither the direct use of the DYNDNS url works, nor the domain. Log look like this:

"errorMessage": "HTTPSConnectionPool(host='homeassistant.example.com', port=443): Max retries exceeded with url: /api/alexa/smart_home (Caused by NewConnectionError('<urllib3.connection.HTTPSConnection object at 0x7f20acbc4040>: Failed to establish a new connection: [Errno -2] Name or service not known'))",

IPV6 ping failed in Cloudshell as network is not reachable... what?

It is not possible to use IPv6 inside Amazon Skills. You must use IPv4.

Oh... okay. So I expect, that in my case, I need to set up a separate proxy server for ipv4 requests tunneling everything to my ipv6 address, don't I? My ISP doesn't provide me a public IPV4 due to CG-NAT / Ds lite... It is plausible....

Oh... okay. So I expect, that in my case, I need to set up a separate proxy server for ipv4 requests tunneling everything to my ipv6 address, don't I? My ISP doesn't provide me a public IPV4 due to CG-NAT / Ds lite... It is plausible....

Had the same issue, check my solution a few posts up.