Tips on working with the FitBit API?

Hi Michael,

Hitting a different API and doing something with the data is a great idea for a project to test and expand your skills!

The Fitbit API is doable, but it's going to require you to learn quite a lot of new things and might take longer than you estimated. If you do go down this path though it will be well worth it, as the things you will learn will be useful for most modern Web APIs!

Before even looking at the fitbit API specifically. Let me say that my biggest tip is to not get discouraged. Building software applications can regularly involve diving into systems that other people have written and making sense of them. Whether the issue is unfamiliar design patterns, incomplete documentation, staggeringly bad code that your surprised works, or staggeringly complex code that looks like you need a math PHD to understand it - you're going to have go on a journey though it, poke and prod it, before you start to understand it enough to work with it. If you can come to enjoy this process you'll be a much more versatile programmer.

I often have two projects or IDEs open at once. One where I'm building the overall application by writing tests and then building out the program to pass them, and another where whenever I hit something I'm unfamiliar with, I write a tiny script to test it out. I also strongly recommend a full blown IDE over workspaces as you start to do your own, more complex projects. I'm a big fan of the JetBrains IDEs (specifically PyCharm for Python and IntelliJ for Rust) and VS Code (for JavaScript). Visual Studio Community (different to VS Code) is also quite good although I've only used it for C# and C. People say good things about Sublime Text as well. It may take a while to get your first IDE working the way you like, but it will pay off. I guess that's my second tip!

Then just start playing with the Web API. Hit an endpoint and see what it comes back with. Can you use the returned payload in your application?

As I suspect you've already realised, for Fitbit this requires a bit of setup. You need to register your application with Fitbit and create an account - which will get you a secret code you can use to identify your app requests as coming from your registered application. As an example, the Google Maps API works the same way.

The Authorization Code Grant Flow is a way for a fitbit user to log your application into fitbit on their behalf and then draw down their data via your API. If you're doing all of this in client side JavaScript you'll need to use the Implicit grant flow instead. Either way, if there's a way to use a "dummy" authorisation for development you should do that and skip this. If not you'll need to allocate some time to learning about OAuth2.0 - it's a standard for these sorts of Authorisations so it's not wasted time, but I would consider it an advanced topic.

Luckily fitbit have an interactive tool that let's you see how their server will respond at each point of the OAuth flow! Check out https://dev.fitbit.com/apps/oauthinteractivetutorial. When going from this tutorial to actual code you'll need to send all of that data to fitbit using your language's OAuth library, process the fitbit response, take the part out of it you need (as described on that page) and use the token to then make your API requests (e.g. to get steps).

If you were looking for a project to complete in a couple of hours, I would shelve this for later and work on something else. Maybe hitting a different part of the Flicker API and doing something else with the data. If you have the time though, this will teach you a lot.

Best of luck regardless on where your next steps take you.

Cheers,

Eric