Understand the technologies used and how to best expose voice experiences to users through Alexa. This session covers custom Alexa skills and building a home automation control from the ground up using Alexa and AWS IoT. Speaker: Rodney Haywood, Solutions Architect Manager, Amazon Web Services

1. © 2017, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Rodney Haywood
Solutions Architect Manager, Amazon Web Services
Level 200
© 2017, Amazon Web Services, Inc. or its Affiliates. All rights reserved.
Voice-Enabling Your Home and Devices
with Amazon Alexa and AWS IoT

2. Building Your Device
Amazon Lex
Amazon Polly
Amazon
Rekognition
AWS IoT

3. Brains are hard to build!

4. Natural Voice Control
Automatic speech recognition (ASR)
and natural language understanding
(NLU) engines.
Always Getting Smarter
New capabilities and services through
machine learning, regular API updates,
feature launches.
Free, Easy Integration
Programming language agnostic service
that makes it easy to integrate Alexa into
your devices, services, and applications.
Best of all, it’s free.

6. Let’s voice enable my
home with Alexa and
AWS IoT by giving her
a new skill.

7. How will we
interact with the
Garage Door?

9. Raspberry Pi
GPIO4

10. Raspberry Pi
IoT thing
GarageDoor
IoT
reported
state
GPIO4
ClosedSensor: true

11. Raspberry Pi
IoT thing
GarageDoor
IoT topic
IoT
reported
state
GPIO4
ClosedSensor: true

12. Raspberry Pi
IoT
rule
IoT thing
GarageDoor
IoT topic
IoT
reported
state
GPIO4
ClosedSensor: true

13. Raspberry Pi
IoT
rule
IoT thing
GarageDoor
IoT topic
IoT
device
shadow
IoT
reported
state
GPIO4
{
"reported":
{
"ClosedSensor": "true",
"OpenedSensor": "false”
}
}
ClosedSensor: true

14. Raspberry Pi
IoT
rule
IoT thing
GarageDoor
IoT topic
$aws/things/GarageDoor
/shadow/update/documents
IoT
device
shadow
IoT
reported
state
GPIO4
{
"reported":
{
"ClosedSensor": "true",
"OpenedSensor": "false”
}
}
Web Socket
ClosedSensor: true

15. Setup
Monitoring the State on the Raspberry PI
1 var GPIO = require('onoff').Gpio;
2 var AWS = require('aws-sdk');
3 var IOTdevicename = 'GarageDoor';
4 var IOTendpoint = 'aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com';
5 var IOTregion = 'ap-southeast-2';
6
7 var iotdata = new AWS.IotData({endpoint: IOTendpoint, region: IOTregion});
8 var closedSwitch = new GPIO(5, 'in', 'both');
9 var openedSwitch = new GPIO(4, 'in', 'both');
10
11 closedSwitch.watch(function (err, value) {
12 updateShadow(IOTdevicename,'{"state": {"reported": {"ClosedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
13 });
14
15 openedSwitch.watch(function (err, value) {
16 updateShadow(IOTdevicename,'{"state": {"reported": {"OpenedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
17 });
18
19 function updateShadow(device, ourPayload) {
20 iotdata.updateThingShadow({ "thingName": device, "payload": ourPayload }, function (err, data) {
21 if (err) { console.log('Opps : ',err); }
22 });
23 }

16. Initialise
Monitoring the State on the Raspberry PI
1 var GPIO = require('onoff').Gpio;
2 var AWS = require('aws-sdk');
3 var IOTdevicename = 'GarageDoor';
4 var IOTendpoint = 'aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com';
5 var IOTregion = 'ap-southeast-2';
6
7 var iotdata = new AWS.IotData({endpoint: IOTendpoint, region: IOTregion});
8 var closedSwitch = new GPIO(5, 'in', 'both');
9 var openedSwitch = new GPIO(4, 'in', 'both');
10
11 closedSwitch.watch(function (err, value) {
12 updateShadow(IOTdevicename,'{"state": {"reported": {"ClosedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
13 });
14
15 openedSwitch.watch(function (err, value) {
16 updateShadow(IOTdevicename,'{"state": {"reported": {"OpenedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
17 });
18
19 function updateShadow(device, ourPayload) {
20 iotdata.updateThingShadow({ "thingName": device, "payload": ourPayload }, function (err, data) {
21 if (err) { console.log('Opps : ',err); }
22 });
23 }

17. Monitor GPIO State
Monitoring the State on the Raspberry PI
1 var GPIO = require('onoff').Gpio;
2 var AWS = require('aws-sdk');
3 var IOTdevicename = 'GarageDoor';
4 var IOTendpoint = 'aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com';
5 var IOTregion = 'ap-southeast-2';
6
7 var iotdata = new AWS.IotData({endpoint: IOTendpoint, region: IOTregion});
8 var closedSwitch = new GPIO(5, 'in', 'both');
9 var openedSwitch = new GPIO(4, 'in', 'both');
10
11 closedSwitch.watch(function (err, value) {
12 updateShadow(IOTdevicename,'{"state": {"reported": {"ClosedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
13 });
14
15 openedSwitch.watch(function (err, value) {
16 updateShadow(IOTdevicename,'{"state": {"reported": {"OpenedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
17 });
18
19 function updateShadow(device, ourPayload) {
20 iotdata.updateThingShadow({ "thingName": device, "payload": ourPayload }, function (err, data) {
21 if (err) { console.log('Opps : ',err); }
22 });
23 }

18. Send payload
Monitoring the State on the Raspberry PI
1 var GPIO = require('onoff').Gpio;
2 var AWS = require('aws-sdk');
3 var IOTdevicename = 'GarageDoor';
4 var IOTendpoint = 'aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com';
5 var IOTregion = 'ap-southeast-2';
6
7 var iotdata = new AWS.IotData({endpoint: IOTendpoint, region: IOTregion});
8 var closedSwitch = new GPIO(5, 'in', 'both');
9 var openedSwitch = new GPIO(4, 'in', 'both');
10
11 closedSwitch.watch(function (err, value) {
12 updateShadow(IOTdevicename,'{"state": {"reported": {"ClosedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
13 });
14
15 openedSwitch.watch(function (err, value) {
16 updateShadow(IOTdevicename,'{"state": {"reported": {"OpenedSensor": ' + ((value == 1) ? '"true"' : '"false"') + '}}}');
17 });
18
19 function updateShadow(device, ourPayload) {
20 iotdata.updateThingShadow({ "thingName": device, "payload": ourPayload }, function (err, data) {
21 if (err) { console.log('Opps : ',err); }
22 });
23 }

19. Setup
Monitoring via WebSocket
1 $(document).ready(function(){
2 var creds = new AWS.Credentials(’<access key>', ’<secret key>');
3 var requestUrl = SigV4Utils.getSignedUrl('aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com', 'ap-southeast-2', creds)
4 var client = new Paho.MQTT.Client(requestUrl, guid());
5 var connectOptions = {
6 onSuccess: function(){
7 client.subscribe("$aws/things/GarageDoor/shadow/update/documents");
8 },
9 useSSL: true, timeout: 10, mqttVersion: 4,
10 onFailure: function(err) {
11 console.log('Connection Failed:', err);
12 }
13 };
14
15 client.onMessageArrived = onShadowUpdate;
16 client.connect(connectOptions);
17 });

20. Connect and monitor topic
Monitoring via WebSocket
1 $(document).ready(function(){
2 var creds = new AWS.Credentials(’<access key>', ’<secret key>');
3 var requestUrl = SigV4Utils.getSignedUrl('aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com', 'ap-southeast-2', creds)
4 var client = new Paho.MQTT.Client(requestUrl, guid());
5 var connectOptions = {
6 onSuccess: function(){
7 client.subscribe("$aws/things/GarageDoor/shadow/update/documents");
8 },
9 useSSL: true, timeout: 10, mqttVersion: 4,
10 onFailure: function(err) {
11 console.log('Connection Failed:', err);
12 }
13 };
14
15 client.onMessageArrived = onShadowUpdate;
16 client.connect(connectOptions);
17 });

21. Parse topic payload to json
Monitoring via WebSocket
18 function onShadowUpdate(message) {
19
20 d = JSON.parse(message.payloadString);
21
22 if (d.current.state.reported.ClosedSensor == 'true' &&
23 d.current.state.reported.OpenedSensor == 'false' &&
24 d.current.metadata.reported.OpenedSensor.timestamp > d.previous.metadata.reported.ClosedSensor.timestamp) {
25
26 var wasOpenedFor = d.current.metadata.reported.OpenedSensor.timestamp –
d.previous.metadata.reported.ClosedSensor.timestamp
27 var duration = d.current.metadata.reported.ClosedSensor.timestamp –
d.current.metadata.reported.OpenedSensor.timestamp
28
29 document.getElementById("state").innerHTML = "Closed";
30 document.getElementById("traveltime").innerHTML = duration.toString() + "s";
31 document.getElementById("opentime").innerHTML = wasOpenedFor.toString() + "s";
32 document.getElementById("message").innerHTML = message.payloadString;
33 }
34 /* ... */
35 }

22. Test for which event
Monitoring via WebSocket
18 function onShadowUpdate(message) {
19
20 d = JSON.parse(message.payloadString);
21
22 if (d.current.state.reported.ClosedSensor == 'true' &&
23 d.current.state.reported.OpenedSensor == 'false' &&
24 d.current.metadata.reported.OpenedSensor.timestamp > d.previous.metadata.reported.ClosedSensor.timestamp) {
25
26 var wasOpenedFor = d.current.metadata.reported.OpenedSensor.timestamp –
d.previous.metadata.reported.ClosedSensor.timestamp
27 var duration = d.current.metadata.reported.ClosedSensor.timestamp –
d.current.metadata.reported.OpenedSensor.timestamp
28
29 document.getElementById("state").innerHTML = "Closed";
30 document.getElementById("traveltime").innerHTML = duration.toString() + "s";
31 document.getElementById("opentime").innerHTML = wasOpenedFor.toString() + "s";
32 document.getElementById("message").innerHTML = message.payloadString;
33 }
34 /* ... */
35 }

23. Pre-calculate some values
Monitoring via WebSocket
18 function onShadowUpdate(message) {
19
20 d = JSON.parse(message.payloadString);
21
22 if (d.current.state.reported.ClosedSensor == 'true' &&
23 d.current.state.reported.OpenedSensor == 'false' &&
24 d.current.metadata.reported.OpenedSensor.timestamp > d.previous.metadata.reported.ClosedSensor.timestamp) {
25
26 var wasOpenedFor = d.current.metadata.reported.OpenedSensor.timestamp –
d.previous.metadata.reported.ClosedSensor.timestamp
27 var duration = d.current.metadata.reported.ClosedSensor.timestamp –
d.current.metadata.reported.OpenedSensor.timestamp
28
29 document.getElementById("state").innerHTML = "Closed";
30 document.getElementById("traveltime").innerHTML = duration.toString() + "s";
31 document.getElementById("opentime").innerHTML = wasOpenedFor.toString() + "s";
32 document.getElementById("message").innerHTML = message.payloadString;
33 }
34 /* ... */
35 }

24. Update the page content
Monitoring via WebSocket
18 function onShadowUpdate(message) {
19
20 d = JSON.parse(message.payloadString);
21
22 if (d.current.state.reported.ClosedSensor == 'true' &&
23 d.current.state.reported.OpenedSensor == 'false' &&
24 d.current.metadata.reported.OpenedSensor.timestamp > d.previous.metadata.reported.ClosedSensor.timestamp) {
25
26 var wasOpenedFor = d.current.metadata.reported.OpenedSensor.timestamp –
d.previous.metadata.reported.ClosedSensor.timestamp
27 var duration = d.current.metadata.reported.ClosedSensor.timestamp –
d.current.metadata.reported.OpenedSensor.timestamp
28
29 document.getElementById("state").innerHTML = "Closed";
30 4ocument.getElementById("traveltime").innerHTML = duration.toString() + "s";
31 document.getElementById("opentime").innerHTML = wasOpenedFor.toString() + "s";
32 document.getElementById("message").innerHTML = message.payloadString;
33 }
34 /* ... */
35 }
1
2
3
4
1 2 34

25. We now have
the door state in
an IoT “thing”.
Lets teach Alexa the skill.

26. Custom Skill Smart Home Skill API

28. Smart Home Skill API Reference
Discovery
• DiscoverAppliancesRequest
• DiscoverApplianceResponse
Control
• DecrementPercentageRequest
• DecrementPercentageConfirmation
• IncrementPercentageRequest
• IncrementPercentageConfirmation
• IncrementTargetTemperatureRequest
• IncrementTargetTemperatureConfirmation
• SetLockStateRequest
• SetLockStateConfirmation
• SetPercentageRequest
• SetPercentageConfirmation
• SetTargetTemperatureRequest
• SetTargetTemperatureConfirmation
• TurnOnRequest
• TurnOnConfirmation
• TurnOffRequest
• TurnOffConfirmation
Query
• GetLockStateRequest
• GetLockStateResponse
• GetTargetTemperatureRequest
• GetTargetTemperatureResponse
• GetTemperatureReadingRequest
• GetTemperatureReadingResponse

29. Alexa smart
home skill
Register
Skill

30. Alexa smart
home skill
Lambda
function
GarageDoor
DiscoverAppliancesRequest
Register
Skill

31. Request type handler
Lambda Function
1 exports.handler = function(event, context) {
2
3 log('Input', event);
4
5 switch (event.header.namespace) {
6
7 case 'Alexa.ConnectedHome.Discovery':
8 handleDiscovery(event, context);
9 break;
10 case 'Alexa.ConnectedHome.Query':
11 handleQuery(event, context);
12 break;
13 default:
14 log('Err', 'No supported namespace: ' + event.header.namespace);
15 context.fail('Something went wrong');
16 break;
17 }
18 };

32. Response Header
Alexa.ConnectedHome.Discovery
19 function handleDiscovery(accessToken, context) {
20 var headers = {
21 namespace: 'Alexa.ConnectedHome.Discovery',
22 name: 'DiscoverAppliancesResponse',
23 payloadVersion: '2'
24 };
25 var payload = {
26 "discoveredAppliances":[
27 {
28 "applianceId": "GarageDoor", // IoT Thing name
29 "friendlyName": "Garage Door", // What we say to Alexa
30 "isReachable": true,
31 "actions": ["getLockState”],
32 "additionalApplianceDetails":{ // Extra data returned in future requests
33 "IOT_Endpoint": "aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com",
34 "IOT_Region": "ap-southeast-2"
35 }
36 }
37 ]
38 }
39 var result = { header: headers, payload: payload };
40 context.succeed(result);
41 }

33. An array of available appliances
Alexa.ConnectedHome.Discovery
19 function handleDiscovery(accessToken, context) {
20 var headers = {
21 namespace: 'Alexa.ConnectedHome.Discovery',
22 name: 'DiscoverAppliancesResponse',
23 payloadVersion: '2'
24 };
25 var payload = {
26 "discoveredAppliances":[
27 {
28 "applianceId": "GarageDoor", // IoT Thing name
29 "friendlyName": "Garage Door", // What we say to Alexa
30 "isReachable": true,
31 "actions": ["getLockState”],
32 "additionalApplianceDetails":{ // Extra data returned in future requests
33 "IOT_Endpoint": "aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com",
34 "IOT_Region": "ap-southeast-2"
35 }
36 }
37 ]
38 }
39 var result = { header: headers, payload: payload };
40 context.succeed(result);
41 }

34. Return header and payload
Alexa.ConnectedHome.Discovery
19 function handleDiscovery(accessToken, context) {
20 var headers = {
21 namespace: 'Alexa.ConnectedHome.Discovery',
22 name: 'DiscoverAppliancesResponse',
23 payloadVersion: '2'
24 };
25 var payload = {
26 "discoveredAppliances":[
27 {
28 "applianceId": "GarageDoor", // IoT Thing name
29 "friendlyName": "Garage Door", // What we say to Alexa
30 "isReachable": true,
31 "actions": ["getLockState”],
32 "additionalApplianceDetails":{ // Extra data returned in future requests
33 "IOT_Endpoint": "aju7zuv46stdy.iot.ap-southeast-2.amazonaws.com",
34 "IOT_Region": "ap-southeast-2"
35 }
36 }
37 ]
38 }
39 var result = { header: headers, payload: payload };
40 context.succeed(result);
41 }

35. Echo
Is the
Garage Door
locked?

36. Echo
Alexa smart
home skill
Lambda
function
GarageDoor
Is the
Garage Door
locked?GetLockStateRequest

37. Echo
Alexa smart
home skill
IoT
device
shadow
Lambda
function
GarageDoor
Is the
Garage Door
locked?
{
"reported":
{
"ClosedSensor": "true",
"OpenedSensor": "false”
}
}
GetLockStateRequest

38. Handle “Is the door locked?” query
Alexa.ConnectedHome.Query
42 function handleQuery(event, context) {
43
44 if (event.header.name === 'GetLockStateRequest') {
45
46 // The payload contains our IoT device details in the appliance which were supplied in the original device discovery
47 var IOTdevicename = event.payload.appliance.applianceId;
48 var IOTendpoint = event.payload.appliance.additionalApplianceDetails.IOT_Endpoint;
49 var IOTregion = event.payload.appliance.additionalApplianceDetails.IOT_Region;
50
51 var AWS = require('aws-sdk');
52 var iotdata = new AWS.IotData({endpoint: IOTendpoint, region: IOTregion});
53 var params = { "thingName" : IOTdevicename};
54
55 iotdata.getThingShadow(params, function (err, data) {
56 if (err) {
57 // Build an error response here.
58 context.fail(result);
59 } else {
60

39. Prepare to read the
IoT Device Shadow
Alexa.ConnectedHome.Query
42 function handleQuery(event, context) {
43
44 if (event.header.name === 'GetLockStateRequest') {
45
46 // The payload contains our IoT device details in the appliance which were supplied in the original device discovery
47 var IOTdevicename = event.payload.appliance.applianceId;
48 var IOTendpoint = event.payload.appliance.additionalApplianceDetails.IOT_Endpoint;
49 var IOTregion = event.payload.appliance.additionalApplianceDetails.IOT_Region;
50
51 var AWS = require('aws-sdk');
52 var iotdata = new AWS.IotData({endpoint: IOTendpoint, region: IOTregion});
53 var params = { "thingName" : IOTdevicename};
54
55 iotdata.getThingShadow(params, function (err, data) {
56 if (err) {
57 // Build an error response here.
58 context.fail(result);
59 } else {
60

40. Call
Alexa.ConnectedHome.Query
42 function handleQuery(event, context) {
43
44 if (event.header.name === 'GetLockStateRequest') {
45
46 // The payload contains our IoT device details in the appliance which were supplied in the original device discovery
47 var IOTdevicename = event.payload.appliance.applianceId;
48 var IOTendpoint = event.payload.appliance.additionalApplianceDetails.IOT_Endpoint;
49 var IOTregion = event.payload.appliance.additionalApplianceDetails.IOT_Region;
50
51 var AWS = require('aws-sdk');
52 var iotdata = new AWS.IotData({endpoint: IOTendpoint, region: IOTregion});
53 var params = { "thingName" : IOTdevicename};
54
55 iotdata.getThingShadow(params, function (err, data) {
56 if (err) {
57 // Build an error response here.
58 context.fail(result);
59 } else {
60

41. Determine the state
Alexa.ConnectedHome.Query
61 var currentState;
62 if (JSON.parse(data.payload).state.reported.ClosedSensor == "false") {
63 currentState = "UNLOCKED";
64 } else {
65 currentState = "LOCKED";
66 }
67
68 var result = {
69 "header":{
70 "messageId": guid(),
71 "name":"GetLockStateResponse",
72 "namespace":"Alexa.ConnectedHome.Query",
73 "payloadVersion":"2"
74 },
75 "payload":{
76 "lockState":currentState,
77 }
78 }
79 context.succeed(result);
80 }
81 });
82 }
83 }

42. Respond with a header and payload
Alexa.ConnectedHome.Query
61 var currentState;
62 if (JSON.parse(data.payload).state.reported.ClosedSensor == "false") {
63 currentState = "UNLOCKED";
64 } else {
65 currentState = "LOCKED";
66 }
67
68 var result = {
69 "header":{
70 "messageId": guid(),
71 "name":"GetLockStateResponse",
72 "namespace":"Alexa.ConnectedHome.Query",
73 "payloadVersion":"2"
74 },
75 "payload":{
76 "lockState":currentState,
77 }
78 }
79 context.succeed(result);
80 }
81 });
82 }
83 }

43. IoT
rule
IoT thing
GarageDoor
IoT topic
$aws/things/GarageDoor
/shadow/update/documents
Lambda
function
setLIFX
LIFX
lightbulb

44. SELECT
"opened" AS message
FROM
'$aws/things/GarageDoor/shadow/update/documents'
WHERE
current.state.reported.ClosedSensor = 'false' AND
current.state.reported.OpenedSensor = 'true' AND
current.metadata.reported.ClosedSensor.timestamp >
previous.metadata.reported.OpenedSensor.timestamp

45. What did we build?

46. Raspberry Pi
Echo
Alexa smart
home skill
IoT
rule
IoT thing
GarageDoor
IoT topic
$aws/things/GarageDoor
/shadow/update/documents
IoT
device
shadow
Lambda
function
setLIFX
Lambda
function
GarageDoor
LIFX
lightbulb
IoT
reported
state
DiscoverAppliancesRequest
Register
Skill
GPIO4
Is the
Garage Door
locked?
{
"reported":
{
"ClosedSensor": "true",
"OpenedSensor": "false”
}
}
GetLockStateRequest
Web Socket

47. 1 $0.0034
* $USD / month Sydney Region

48. 1 $0.0034
100 $0.34
* $USD / month Sydney Region

49. 1 $0.0034
100 $0.34
10,000 $33.78
* $USD / month Sydney Region

50. Its easy to voice enable
things with Alexa and
AWS IoT.
What could you build?

51. Thank you!