README.md

Code-Based Linking (CBL) Module

The Alexa Auto SDK CBL module provides the features required by a platform implementation to fully handle the authentication flow with Alexa. The platform implementation is responsible for storing and supplying the refresh token to the SDK.

Table of Contents

• Sequence Diagrams
• Using CBL

Sequence Diagrams

The following sequence diagrams provide an overview of the authentication flow and the process of refreshing the authentication when the application provides a valid refresh token.

Initial authentication flow

This diagram provides an overview of the initial authenticaion flow.

Refreshing token

This diagram provides an overview of how CBL refreshes your authentication on startup.

Using CBL

To implement a custom CBL handler, extend the CBL class:

#include <AACE/CBL/CBL.h>

class MyCBLHandler : public aace::cbl::CBL {

    // Notifing the platform for a state change in authorization flow with reason
    void cblStateChanged( CBLState state, CBLStateChangedReason reason, const std::string& url, const std::string& code ) {
        // Display url and code when supplied
        // Track state
    }

    void clearRefreshToken() {
        // Remove refresh token from platform application
    }

    void setRefreshToken( const std::string& refreshToken ) {
        // Set refresh token
        // The platform application is responsible for storing the refresh token securely
    }

    std::string getRefreshToken() {
        // Return refresh token, if available, otherwise empty string
    }

    void setUserProfile( const std::string& name, const std::string& email ) {
        // Set name and email
        // The platform application will be notified during login
    }

    // Begin authorization flow
    start();
    ...

    // Cancel authorization flow
    cancel();
    ...

    // Reset authorization state
    reset();
    ...
};

// Register a CBL handler with the Engine
std::shared_ptr<CBL> cbl = std::make_shared<MyCBLHandler>();
engine->registerPlatformInterface( cbl );

Use this configuration to enable a user profile:

{
    "aace.cbl": {
        "enableUserProfile": true
    }
}