I’ve built two VS Code extensions and thought it would be good to share my thoughts on the best way to kick start building your first extension. Key topics I will cover here are the basics about the build, unit testing and a publish/deployment pipeline.
There has been plenty of interest in React Suspense with many articles and experimental code snippets to test it out. I thought I would read more about it and give my understanding of why you might want to use it. Below is my summary after reading through the React docs about concurrent mode and Suspense.
Now that React context has become more established in the community we are seeing a lot of great usages of it. Reflecting on a previous post about Higher-order components (HOC) vs Render props, I rarely use HOC and now generally choose between Context or Render props. With the introduction of hooks and in particular useContext hook, React context is more accessible and has become a go-to approach to solving complex state management. However, there are other options to handle these cross-cutting concerns and so we should be clear on why we are using context. Let’s explore why and how to use React context.
I created LanceDarkly, a VS Code extension to help make it easy to manage LaunchDarkly toggles without leaving the editor. What are LaunchDarkly toggles? It’s a service which enables a way of remotely managing the visibility of app features. Toggles are especially handy for trunk-based development and continuous deployment practices by enabling engineers to build features without the end-user seeing it. When that feature is ready, the toggle can be switched on to make the feature visible for all. LaunchDarkly toggles have many other options including splitting traffic to provide a way to split test.
There is an issue with unit testing VS Code extensions. The vscode dependency - which is needed to utilise the editor’s features - will error when running unit tests. Essentially it is a third party dependency which is out of your control, so the best thing to do is to mock the API. I will be using Jest and will explain how to use its mocking features to handle the VS Code dependency.
This won’t be a deep dive into unit testing React components but I will present some options for mocking external services. This is seen as good practice at the unit test level, as we don’t want these tests dependant on an external API which will slow the feedback down and make the test fragile. Mocking is typically used quite loosely and there are plenty of nuances when we throw spies and stubs in the mix. However, they do have a particular meaning and they are all placed under the generic term of Test Double as described by Martin Fowler.
In the previous article I talked about security concerns around storing tokens in localStorage. I thought it would be worth exploring how to use HttpOnly cookies when making requests from a React client-side app. This will include making changes to the Apollo Graphql Server to manage cookies from the client. In this post I will go through the changes needed to enable storing JWTs in HttpOnly cookies from sending headers.
This is the continuation of JWT for authentication using Apollo Graphql server and will show an example of how to send JWTs for each request from the client to the GraphQL server, and how to handle updated tokens when a user returns for a new session in the client.
This tutorial will focus on the key features needed to send and receive tokens, meaning there is no complete example output to try at the end. The aim is to help you integrate authentication into your own app.
This post will cover managing complex state at a feature level rather than the entire site. React hooks have enabled developers to have cleaner functional components which help to rationalise our component logic with ease.
Take useState hook, it’s one line of code that can be used to manage the state of a component rather than having to create a class component with the addition of boiler code. This is great because we are keeping simple things clear!
However, there are features that are inherently complex as they could have many nested child components and need to alter the state.
What options are there to manage this complexity in React?