Chapter 8. Debugging h2

Spending nearly 2 decades with a protocol means 20 years of tools for monitoring and debugging. Now HTTP/2 comes along, and your old way of doing things no longer works. This could be a mission-critical blocker until tools are updated or replaced. Regardless, h2 is a different though vaguely similar beast to h1. Much of what worked before will work now, but the differences are important. Fortunately, there is already a rich supply of test and debugging tools available, ranging from things that are specific to HTTP/2 to updates to your current toolsets that you already use.

Web Browser Developer Tools

Most modern web browsers include web developer tools that are useful for debugging h2. The following sections are a few examples of how you can follow an h2 stream, identify h2 priorities and dependencies, and understand Server Push using Chrome and Firefox Developer Tools. Note that similar concepts can be applied to other popular browsers like Safari, Edge, or Opera.

Chrome Developer Tools

Over the past few years the Chrome browser has gained adoption among web developers in part due to the increasing functionality of its Web Developer tools.1 Being familiar with their capabilities can provide you an advantage for solving your next technical snafu. Pull up the developer tool by choosing View → Developer → Developer Tools in the Chrome menu.

Net internals

Chrome net-internals2 can be accessed by typing chrome://net-internals in Chrome’s address bar. These ...

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