bmwe30is / dexcom-test-app

Quick and dirty application to get an authentication token from Dexcom's API.

Dexcom Test Application

This is a basic application aimed at the newly released (as of Sept 19, 2017) Dexcom API.

Application Set Up

• Execute npm install to download and install dependencies. See package.json for further information.

• You will need to create a .env file with the following entries:

  CLIENT_ID: Your Dexcom client ID.

  CLIENT_SECRET: Your Dexcom client secret.

  DEXCOM_API_HOST: Which Dexcom environment you want to use. This can be either sandbox-api.dexcom or api.dexcom.com.

  PORT: The port on which you want to run locally.

• Run the application by executing npm start.

Pre-made Authentication Routes

There are currently four routes implemented:

• / a basic index page that lets you know the app is running in the browser.
• /auth this does the work of redirecting you to Dexcom's site where you can log in with a sandbox user or a prod user. Once authenticated, the app will take you to the /token route.
• /token does the work of obtaining a bearer token once the user has authenticated to Dexcom. Upon successful authentication by the user, you will receive a JSON payload with the bearer token as defined in Dexcom's documentation.
• /token/:refreshToken takes a refresh token as a path parameter and allows you to easily refresh your bearer token.

Dexcom API Wrapper Routes

The app wraps all five of the Dexcom endpoints using their URI pattern. I simply pass on the query parameters back to Dexcom's API.

Note(s)

• The redirect URL's passed to the Dexcom authentication endpoints assume redirection back to http://localhost:8080.
• Once you land on http://localhost:8080/token?code=YOUR_AUTH_CODE&state=auth (after hitting the /token path) you can simply refresh this page to get a new access token.

Outstanding Optimizations

• Right now I'm passing the bearer token as a query parameter to our wrapper API. I'm using Postman to test the application locally, where I set the bearer token as a query parameter.

  On the next revision, I'll transfer the token to an actual header where it's supposed to live.

For example, when I POST to the statistics endpoint, I use the code query parameter (it should actually be named bearerToken):