alexa_web_api 1.1.0 alexa_web_api: ^1.1.0 copied to clipboard
A Dart-JavaScript interoperability for Alexa Web API for Games.
A Dart-JavaScript interoperability for Alexa Web API for Games. Alexa Web API for Games lets you create rich, immersive voice-enabled games by combining Alexa Skills Kit (ASK) directives with familiar web technologies.
Features #
Alexa Objects - Client #
Property | Description | Supported |
---|---|---|
capabilities | The device capabilities. For details, see Microphone and Capability. |
✅ |
performance | Provides the interface to get the available memory on the device. For details, see Performance. |
✅ |
skill | Provides the interfaces to communicate with your skill. For details, see onMessage and sendMessage . |
✅ |
speech | Provides the interfaces to receive Alexa speech events. For details, see Alexa Speech Input. |
✅ |
version | Version of the Alexa client. If you don't specify a version, the latest version is used. |
✅ |
voice | Provides the interfaces to open the microphone on the device to receive user utterances. For details, see Alexa Voice. |
✅ |
Functions #
Property | Description | Supported |
---|---|---|
create | Establish the connection to Alexa on the device. When the future is completed successfully, an AlexaReadyPayload object is returned. Otherwise, when the future completes with an error, an ErrorWithCode object is returned. For details, see create. | ➖ * |
*Even though a MessageProvider
can be passed as an parameter in the Alexa.create
function, doing this will cause an exception to be thrown.
Extensions #
Property | Description | Supported |
---|---|---|
Entity-Sensing | Alexa-enabled devices with entity-sensing capabilities can detect the presence of the user. For details, see Entity-Sensing. |
❌ |
Smart-Motion | Alexa-enabled devices with smart-motion capabilities can rotate the device screen to turn toward and follow engaged users. For details, see Smart-Motion. |
❌ |
Legend
✅ Supported
❌ Not supported
➖ Partially supported
Usage #
Add the Alexa JavaScript library to your app #
To load the Alexa JavaScript library, include the URL in a script tag on your HTML page, as shown in the following example.
<head>
<script src="https://cdn.html.games.alexa.a2z.com/alexa-html/latest/alexa-html.js"></script>
</head>
Create the Alexa client #
Your app communicates with the device and with your skill with the Alexa Client
object. To prevent the client from being available before it's ready to serve requests, create the Alexa Client
object with a static factory function. Invoke the function one time on each page.
The following example shows Alexa Client
object initialization.
Alexa.create(CreateClientOptions(version: '1.1')).then((args) {
AlexaReadyPayload alexaClient = args.alexa;
querySelector('#debugElement')?.innerHtml = 'Alexa is ready :)';
}).onError((ErrorWithCode error, stackTrace) {
querySelector('#debugElement')?.innerHtml = 'Alexa not ready :(';
});
Capabilities #
Check the device capabilities using the capabilities
interface.
The following example shows a check for PushToTalk capability using a Microphone
object.
if (alexaClient.capabilities.microphone.supportsPushToTalk) {
// Prompt the user to press the microphone button
...
};
The following example shows a check for WakeWord capability using a Microphone
object.
if (alexaClient.capabilities.microphone.supportsWakeWord) {
// Prompt the user to press the microphone button
...
};
Performance #
Use the performance interface to get the available memory on the device. This interface is useful in development for optimizing assets and debugging across device types.
Important: Don't use the performance interface in production because the invocation can negatively affect device performance.
The following example shows logging the available memory.
alexaClient.performance.getMemoryInfo().then((memInfo) => {
// log memInfo
}).onError((MemoryInfoError error, stackTrace) {
// log error caused by memInfo
});
onMessage #
Use the alexaClient.skill.onMessage
to register a listener to handle messages sent from your skill. The messages sent to your listener are independent of the messages your app sends to your skill. The format of the message
sent from the skill is agreed on between the app and the skill. The app can only register one callback, so the callback function should include logic to handle different messages based on the data provided within the message
. Messages can't be received until you register the listener. If you need information from the skill on start-up, use the message
returned in the successful create
interface.
The following example shows registering a listener function called messageReceivedCallback
.
main() {
// Register a listener to receive a message from your skill
alexaClient.skill.onMessage(allowInterop(_messageReceivedCallback));
}
// Implement the listener
void _messageReceivedCallback(dynamic message) {
// Process message (JavaScript object) from your skill
};
sendMessage #
To send a message to your skill from your web app, use alexaClient.skill.sendMessage
interface. The interface takes a data payload and an optional callback for handling the response. The API results in an Alexa.Presentation.HTML.Message
to your skill.
Important: You can't send more than two messages per second to the skill. Use the optional callback on alexa.skill.sendMessage()
to catch throttling errors caused when your app exceeds this limit. The MessageSendResponse
returns error 429 (Too Many Requests) to your callback.
The following example shows sending a message to the skill.
main() {
// Send a message to your skill
alexaClient.skill.sendMessage(message, allowInterop(_messageSentCallback));
}
// Check the results of the MessageSendResponse
void _messageReceivedCallback(MessageSendResponse sendResponse) {
// Handle response codes
};
Known Issues #
- Currently Extensions are not supported.
- For more know issues, please see https://developer.amazon.com/en-US/docs/alexa/web-api-for-games/known-issues.html.
Contributing to this package #
If you would like to contribute to the plugin, check out our contribution guide.
Disclaimers #
This is not an Amazon product.