How we’re winning the battle against flaky tests

Testing is a crucial part of maintaining a code base, but not all tests validate what they’re testing for. Flaky tests—tests that fail sometimes but not always—are a universal problem, particularly in UI testing. In this blog post, we will discuss a new and simple approach we have taken to solve this problem. In particular, we found that a large fraction of most test code is setting up the conditions to test the actual business-logic we are interested in, and consequently a lot of the flakiness is due to errors in this setup phase. However, these errors don’t tell us anything about whether the primary test condition succeeded or failed,

Read more

Meet Bandaid, the Dropbox service proxy

With this post we begin a series of articles about our Service Oriented Architecture components at Dropbox, and the approaches we took in designing them. Bandaid, our service proxy, is one of these components. Follow along as we discuss Bandaid’s internal design and the approaches we chose for the implementation.

Bandaid started as a reverse proxy that compensated for inefficiencies in our server-side services. Later we developed it into a service proxy that accelerated adoption of Service Oriented Architecture at Dropbox.

A reverse proxy is a device or service that forwards requests from multiple clients to servers (i.e.

Read more

Deploying IPv6 in Dropbox Edge Network

In the past few months, we have gradually enabled IPv6 for all user-facing services in Dropbox edge network. We are serving about 15% of daily user requests in IPv6 globally. In this article, we share our experiences and lessons from enabling IPv6 in the edge network. We will cover the IPv6 design in the edge, the changes we made to support IPv6, how IPv6 was tested and rolled out to users, and issues we encountered. Note that this article is not about enabling IPv6 for internal services in our data centers, but rather focuses on making IPv6 available to users.

Read more

Handling system failures during payment communication

Handling system failures during payment processing requires real-time identification of the issues in addition to offline detection, with the goal of eventual consistency. No matter what goes wrong, our top priority is to make sure that customers receive service for which they’ve been charged, and aren’t charged for service they haven’t received. Accurate payment processing is a crucial element in being worthy of trust, a core Dropbox company value.

In a standard system of this kind, failures might result in page load errors or a failed database transaction. System failures during a charge request can result in uncertainty about where the money for that request ended up: is it in our company’s account or still in the customer’s account?

Read more

Infrastructure update: evolution of the Dropbox backbone network

In our previous post, we provided an overview of the global edge network that we deployed to improve performance for our users around the world. We built this edge network over the last two years as part of a strategy to deliver the benefits of Magic Pocket.

Alongside our edge network, we launched a global backbone network that connects our data centers in North America not only to each other, but also to the edge nodes around the world. In this blog, we’ll first review how we went about building out this backbone network and then discuss the benefits that it’s delivering for us and for our users.

Read more

Evolution of Dropbox’s Edge Network

Update (November 14, 2017): Miami, Sydney, Paris, Milan and Madrid have been added to the Dropbox Edge Network.

Since launching Magic Pocket last year, we’ve been storing and serving more than 90 percent of our users’ data on our own custom-built infrastructure, which has helped us to be more efficient and improved performance for our users globally.

But with about 75 percent of our users located outside of the United States, moving onto our own custom-built data center was just the first step in realizing these benefits. As our data centers grew,

Read more