Category: APIs

mitmproxy is my preferred proxy for API testing these days. I'm using it mostly in reverse mode though, so I thought I'd capture my setup in case it's useful for anyone else. My main use case is to inspect the traffic coming into the API server and being returned, mostly when running tests against it. Where mitmproxy is typically used as a proxy to monitor traffic passing into/out of a client application, for this I'm concerned with the server's handling. Reverse mode lets me inspect and adjust the traffic as I go along. I start up the proxy, configure the tests to point to it instead of the actual server, and I'm all set.

OpenAPI tags have always been annoying: user-supplied arbitrary data for endpoints should be a fabulous feature - but the documentation tools seem to think that tags are only for them so it becomes more difficult to use tags for other purposes. In fact it is very useful to be able to tag endpoints with lots of different categories of data and so in OpenAPI 3.2, tags were enhanced to include an additional "kind" field so that different kinds of tag could be used.

OpenAPI has always had support for simple tags, but the OpenAPI 3.2 release brought in some serious tag upgrades including a summary field, a "kind" field with registry, - and the ability to nest tags which is the focus of today's post. If one level of organisation isn't enough for your API (and on bigger APIs I'd argue it shouldn't be) then the ability to indicate which tag is the parent of this tag will be a good feature to adopt when you upgrade your OpenAPI descriptions.

Today I'm sharing a quick-and-dirty script to take an OpenAPI description, spin up a docs server locally, and copy the URL into your clipboard. I also use a bit of glob expansion in my script to find the right folder, because I have a lot of APIs with long and formulaic directory names (TM Forum members know this story). I'm spinning up Scalar here as it's my current favourite just-works local API docs platform.

The more I work on API standards, the more I realise how few teams understand that they can adopt the standards and, without breaking any contract, adapt them to make a strong interface for their own application. One of my favourite examples is to add enums where a standard interface cannot dictate the exact values, but in your own implementation it is very helpful to do so.