tracking-bot

A sample application that uses Lex, Polly, Cognito, and DynamobDB for a the implementation of a tracking application. A model described in a json file drives the creation of a Lex Bot using CloudFormation custom resources. This model can be extended, changed, replaced, reused easily driving the creation of a new tracking application with a web and android user interface. It is a model driven approach.

A tracking application provides the ability to easily record and report on metrics about activities being completed by an individual. For example, the sample Resolutions model provided records goals one might typically make during a new years party for the upcoming year. For example these might be to volunteer more time, to give more funds to charity, to donate more articles to charity, to participate in more community events, etc.

There are four main components in this application: LexAppBuilder, LexWebUi (in the aws-lex-web-ui folder), dashboard-app, and an Android App contained in the TrackingBot-aws-my-sample-app-android folder.

LexAppBuilder

Responsible for building the Lex implementation based on a model. The model used in the sample Resolutions app is defined at LexAppBuilder/model/TrackingBotModel.json. This component is home to the backend processing performed by a python Lambda function which takes input from the Lex service for dialog and fulfilment code hooks and aggregates responses in DynamoDB based on categories defined in the model.

The LexAppBuilder uses the model to create the Lex stack. One can change the model and updates will be automatically produced via CodePipeline.

The LexAppBuilder uses the model to create a Lex Bot automatically. A Bot consists of a set of Intents, Utterances, Slots, and SlotTypes. The model drives this creation. Other than editing the model, no additional work is needed at the Bot level.

LexWebUi

This component is responsible for providing a web based interface to interact with Lex. It is incorporated as a submodule and presented as an iframe in the dashboard-app. The LexWebUi can be used as a component in other chat based applications.

dashboard-app

Provides a sample dashboard generating simple radial pie charts to show progress towards goals specified in the tracking bot model. The dashboard-app presents results based on categories defined in the model. It also presents the LexWebUi as an IFrame to allow easy user interaction.

TrackingBot-aws-my-sample-app-android

The Android app provides a second mechanism for recording results. The Android App, much like the web UI, allows a user to input information via voice using Lex and see a quick summary of results in a simple dashboard embedded in the App. It is similar to the dashboard-app however it is less sophisticated. In its present form this app only enables voice input. A similar chat style interface could also be developed.

The model defined in the LexAppBuilder is automatically incorporated into the Android App. When edits to the model committed to githup, the Android app will be rebuilt.

CodePipeline and CodeBuild

The logic to build and deploy the applications is driven by the master-cft.yaml file. It contains the logic to create the initial stack via CloudFormation. A single CodePipeline with two actions is created.

The first action calls masterBuild.js. This nodejs based script performs the following:

• builds the aws-lex-web-ui and stores this in an S3 bucket
• builds the dashboard-app and stores this in a separate S3 bucket. The dashboard-app integrates the aws-lex-web-ui as an IFrame.
• runs the LexAppBuilder which creates a stack based on the supplied model. This stack includes setting up DynamoDB tables and setting up the Lex Bot using custom resources implemented to build Lex runtime components.

The second action calls masterBuildAndroid.js. This build is responsible for compiling the Android app and uploading the apk to an S3 artifact bucket. The buildAndroid.sh script is as utilized to support building the android app.

After the initial stack has been deployed using master-cft.yaml, the build process will create a second CloudFormation stack which builds up the Lex Bot. Several outputs are provided by master-cft.yaml:

• a link to the dashboard-app
• a link to the android apk file
• a link to the CodePipeline in the AWS Console

CloudWatch logs for each build will provide detail results of the build process. The logs also indicate exactly how masterBuild.js and masterBuildAndroid.js are invoked.

Sample code only

The code provided in this example is sample code. It is used to demonstrate the art of the possible. It tells a story about how multiple AWS services can be integrated into a functioning app. It demonstrates how a model can be used to drive the creation of a Lex Bot.

Note, there are many areas for improvement. As time progresses we hope to integrate new AWS services / features into this sample and improve the overall code base.