Skill Flow Builder Content Framework

Warning DEPRECATED The Alexa Games team will no longer support or maintain this official distribution of Skill Flow Builder. Thank you to all the folks who have used SFB to make great Alexa skills over the years!

The Skill Flow Builder Content Framework contains the core collection of utility and driver functionalities that powers the Editor and the CLI. It handles the interpretation of SFB’s domain-specific language into a narrative structure, i.e., importing, validating, and creating interactive story skills for Alexa.

Visit Skill Flow Builder on Github for more information.

Getting Started

Prerequisites

The following needs to be installed and configured:

Node.js (with npm) # Note: Requires Node.js version >= 10.15.
Yarn

Compiling

yarn install && yarn compile

The compiled code is built into the dist/ directory. The Skill Flow Builder Framework requires other core modules to be built. To build all the modules in the packages/ directory at once, run yarn build-modules.

Testing

yarn test

This will run all unit tests in the test/ directory.

Package Structure

The SFB Framework package structure looks like this.

packages/sfb-f/
└── bakeUtilities/ # Schemas for Intents & Interaction Models
└── driver/ # Drvers for Audio and Scene responses
└── exportHandlers/ # Exporters of SFB project files
└── extensions/ # Extensions to modify the incoming/outgoing content
└── importer/ # Importers for SFB project files
└── importPlugins/ # Plugins that help with importing
└── story/ # SFB story methods
└── test/ # Tests
└── transformers/ # Transforms segments for use in SFB
└── verificationHandlers/ # Verifies integrity of SFB project files
└─── ...

Build Life Cycle

The following is a lifecycle for Skill Flow Builder project when the build process is executed by running alexa-sfb build, and is executed as part of the deploy process when using alexa-sfb deploy.

1. Code Build: Install dependencies and run compile script for code/ directory.
2. Pre-Import: Run extendSourceContent() on content source (included *.abc files) for the attached ImporterExtensions.
3. Post-Import: Run extendImportedContent() on the resulting StoryMetadata for all attached ImporterExtensions, and write the result to baked/{locale}/baked_story.json.
4. Staging: Generate a deployment payload in .deploy/ with the ask new command, then copy the built code, the imported story, and assets from content/{locale}/resources to the resulting deployment payload directory. If metadata exists copy skill.json and ask_config from the metadata directory for appropriate stages.
5. Deploy (if you are running alexa-sfb deploy): Run ask deploy on the deployment payload.

Skill Runtime Life Cycle

The following steps show the runtime life cycle when requests come in to your Skill Flow Builder deployed skill's lambda.

1. ASK SDK pre-request handler: The request and event object are enveloped by ASK SDK, and persistent skill state is retrieved with attached PersistenceAdapter.
2. Skill Flow Builder Request Handler: ASK SDK's HandlerInput is passed to SFBRequestHandler for processing, then the handler calls SFBDriver with current skill state and incoming request.
3. Skill Flow Builder Driver Pre Run: Run pre() for all attached instances of DriverExtension. Default DriverExtension like AlexaExtension would parse the request in to UserInput object at this step.
4. Skill Flow Builder Driver Run: The core logic for taking the incoming user input, StoryMetadata, and current skill state, is executed at this step along with running custom instructions defined in attached InstructionExtension.
5. Skill Flow Builder Driver Post Run: Run post() for all attached instances of DriverExtension. Default DriverExtension like AlexaExtension would generate an Alexa skill response given the post run state at this step.

Contributing

The SFB Framework module contains the core logic for Skill Flow Builder’s engine, which is utilized by both the Alexa Skill runtime and the Skill Flow Builder editor. You can locally recompile the source code with yarn compile, but you will have to run yarn build-modules, in order for your changes to show appropriately in other modules.