The Workers team here at Cloudflare has been hard at work shipping a bunch of new features in the last year and we’ve seen some amazing things built with the tools we’ve provided. However, as my uncle once said, with great serverless platform growth comes great responsibility.

One of the ways we can help is by ensuring that deploying and maintaining your Workers scripts is a low risk endeavor. Rotating a set of API keys shouldn’t require risking downtime through code edits and redeployments and in some cases it may not make sense for the developer writing the script to know the actual API key value at all. To help tackle this problem, we’re releasing Secrets and Environment Variables to the Wrangler CLI and Workers Dashboard.

Supporting secrets

As we started to design support for secrets in Workers we had a sense that this was already a big concern for a lot of our users but we wanted to learn about all of the use cases to ensure we were building the right thing. We headed to the community forums, twitter, and the inbox of Louis Grace, business development representative extraordinaire, for some anecdotes about Secrets usage. We also sent out a survey to our existing users to learn about use cases and pain points.

We learned that even though there was already a way to store secrets without exposing them via Workers KV, the solution was not very intuitive, nor did it meet all the needs of our users. Many users didn’t even know we had an interim solution in place. Recognizing that we were not the first platform to encounter this problem, we surveyed the existing landscape of Platform as a Service offerings to get a better sense for what our users would expect of us.

Deciding on a solution

One of the first things we found was that not all environment variables are created equal. While the simplest use case for having a defined environment variable may be storing a piece of text that can be updated no matter where it is referenced in a script, sometimes those variables may have higher stakes associated with them. If you’re storing an API key that controls access to an important system, you may not want to allow anyone with dashboard access to see it, maybe not even the developers themselves.

With this in mind, we had to ensure the feature covered two different use cases: one for storing variables in plain text where you could see the variable being referenced and make edits to it and another where the variable would be encrypted as soon as you save it, never to be seen again. This way, we were able to serve both needs of our users, side by side, without one compromising for the other.

Testing our prototypes

Once we had a fairly good idea of what we wanted to build, we built some prototypes and rough implementations in staging environments so we would be able to perform some usability testing. We wrangled up some developers and observed them as they performed a series of tasks where they were asked to add some secrets and plain-text environment variables, reference them in one of their Workers, and bind their Worker to a Worker KV namespace.

Along the way we also asked questions to understand the developer’s professional background, familiarity with the product, and the use cases they’ve had for using Workers in the past along with any pain points they experienced.

While we were testing the new dashboard interface we also began testing the usability of the Wrangler CLI. We had Wrangler users perform the same tasks as the Workers dashboard users to help us find out if users are expecting different things out of their command-line tooling.

Findings and fixes

Through our testing we were able to make a number of changes before the final release. Some of the smaller changes included things like adjusting the behavior of form fields to ensure users knew which variable would be associated with each value. We also made larger changes like electing to separate the KV namespace bindings from the other environment variables as a way to emphasize that KV namespace bindings are not the keys and values themselves but a reference to a namespace where those keys are stored.

Cina, one of our engineers, put together a proposal to align some of our terminology with the terms that our developers were naturally using to describe their workflow. In Wrangler users were accustomed to referencing their KV namespaces by adding a KV namespace binding so when they came to the Workers dashboard interface and saw a field called “KV Variables” they were often confused, thinking they were adding keys and values to the namespace itself instead of establishing a variable that could be used to reference the namespace. As a fix, we decided to call it a “KV namespace binding” throughout the experience.

Try it out

Environment variables are available now with the Wrangler CLI and in the Workers Dashboard so go ahead and give them a shot today!

Adding a secret with Wrangler
Managing environment variables and KV bindings in the Workers Dashboard

As we continue to build out the Workers platform we’d love to hear from you. Let us know if you’re interested in participating in user research or just have something to say as we’d love to hear from you.