Open Standards for APIs

I work or have worked with APIs of all sorts of standards, sometimes many standards at once – or none. Each standard exists for a purpose and might be a great fit, or a terrible fit for other purposes. Today’s post is a recap of some of the common API standards around and what you need to know about each one. Continue reading

Lint APIs with Redocly CLI

API governance needs good tooling, and rules that fit – so today’s post covers both.

Fun fact: I work at Redocly and had used the tool for years, but recently realised that I have a post about a different tool in the archives of my blog, but no Redocly post. So here’s the Lorna-recommended version of OpenAPI linting with Redocly CLI. Continue reading

API Description Pipelines

Working on API tools, I get to see inside lots of different organisations’ API projects and processes. Every scenario is different, but a common theme is that many companies use a more complicated API description workflow than you see in conference slide decks! Without sharing any one organisation’s secrets, this article shares a rundown of some typical steps that might show up in an API description pipeline. Continue reading

API Linting Levels

I’ve been thinking about API linting lately, partly because I work on a tool for API linting in my day job, and partly because I get quite a lot of questions from teams wanting to improve their API quality. The “best” ruleset depends entirely on your context, where you are in your API practice journey, and how much you want to invest in the API in question. I typically use a 4-levels model of API linting readiness, and I’m sharing them so that you can find yourself on the map and see where you might go from here. Continue reading

Add OpenAI flags to OpenAPI descriptions

With OpenAI’s new Actions feature allowing you to get a GPT that uses your own API, many new doors are open. However giving an AI an access token the keys to your API and telling it to have fun may lead you to realise that one of the doors available leads to the empty lift shaft of overwritten data, or the bottomless well of cloud bill shock. To reduce the risks, OpenAI supports an extension x-openai-isConsequential that you can add to your OpenAPI description, to indicate which endpoints should not be called without a human confirmation step.

I’m not doing much with OpenAI right now, but I do plenty with OpenAPI and the question “how do I add this field to my existing API description?” is one that I can answer! What’s more, you can use the advice in this post to add other extensions or additions to your OpenAPI descriptions using Overlays, this advice isn’t OpenAI-specific, but it’s used in the examples. Continue reading

When to version bump your OpenAPI description

I’ve heard a variety of bad advice (and some untruths!) regarding how to version your OpenAPI description lately. Rather than dig into those, instead I’ll share my opinion on how I like to version API descriptions in my own projects. Every API project is different, but perhaps there’s something here that can help your project too. Continue reading

Visualise OpenAPI with Blockly

Giving talks about OpenAPI often means lots and lots of slides of YAML. In fact, one of my talks even contains a “warning, contains yaml” slide! If you aren’t a professional yaml developer, it can be difficult to digest and learn from, and so I wanted to do better. The various elements are nested inside one another, and so I had this idea to build a representation of OpenAPI using Blockly (the tooling also used for Scratch, if you’ve seen that).

Showing tags with descriptions
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Tips for better documentation with OpenAPI

I love documentation, which is supposed to be rare for software engineers. I am pretty sure that loving documentation is actually very common, but not very cool and so few people admit to it! I love reading good docs, and so I love writing them too. Between hanging out in the Write the Docs community, and recently being at the APItheDocs conference, I’ve answered a bunch of questions about getting good documentation from an OpenAPI document, so I thought I’d round them up in case it’s useful. Continue reading

Improve Existing OpenAPI Descriptions

I’m a firm fan of a design-first approach to building APIs, and advocate for it at every opportunity. Repeatedly. Design-first means that an API change starts in the OpenAPI description, gets reviewed and approved by the stakeholders, and then gets built afterwards.

I also live in the real world, where OpenAPI descriptions get generated from existing codebases, and engineering teams lack either the knowledge or the enthusiasm to modernise their processes. With a generated OpenAPI description, everything else that OpenAPI enables is likely to be disappointing, because the description only contains the information that was in the serverside code, and if you’re lucky some comment metadata. Enter OpenAPI Overlays, a way to describe alterations to an existing OpenAPI description that can be reapplied every time that description changes. Continue reading

What’s New in OpenAPI 3.1

With OpenAPI 3.1 coming “soon”, I gave a talk at APIDays Paris about what to expect. But I’m a great fan of the written word as reference so here’s a written recap of what’s in the next OpenAPI release.

Top features:
– Compatible with JSON Schema 2020-12
– Webhook support
– Many other minor improvements
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