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'))

Hi everyone,

I´ve tried to follow this guide carefully, but it does not work for me even though I got everything connected. Testing the lambda function with the access token seems to work, but it returns an empty list of endpoints:

{
  "event": {
    "header": {
      "namespace": "Alexa.Discovery",
      "name": "Discover.Response",
      "messageId": "7be269dc-01b6-4eb8-9184-313063f33557",
      "payloadVersion": "3"
    },
    "payload": {
      "endpoints": []
    }
  }
}

My home assistant lists a few sensors when checking https://{home_assistant_url}/config/voice-assistants/expose and these sensors are visible at the Dashboard and appear online. But still, the list of endpoints is empty, so Alexa is anable to add any devices.

I added this (no filtering) into my configuration.yaml:

`alexa:
  smart_home:`

I am quite new to home assistant so this might be a simple configuration mistake by myself.

I am using Home Assistant Supervised version 2024.11.2 running on Ubuntu 24.04 Server