Skip to main content

Using HTTP Files in VS Code with REST Client

I regularly switch between multiple IDEs, mostly VS Code and Visual Studio but sometimes also Rider or Cursor. One of the Visual Studio features I miss when using VS Code is the support for HTTP files.

What if I told you that there is a way to use HTTP files in VS Code? Enter the REST Client extension for Visual Studio Code, a lightweight, powerful tool that lets you test APIs without ever leaving your editor.

What is the REST client extension?

Similar to the HTTP support in Visual Studio, the REST Client extension allows you to send HTTP requests and view responses directly in VS Code. It's minimal, scriptable, and integrates seamlessly into your existing workflow. It offers the same functionality as in Visual Studio and more:

  •   .http and .rest file extensions support
  • Syntax highlight (Request and Response)        
  • Auto completion for method, url, header, custom/system variables, mime types and so on
  • Comments (line starts with # or //) support
  • Support json and xml body indentation, comment shortcut and auto closing brackets
  • Code snippets for operations like GET and POST
  • Support navigate to symbol definitions(request and file level custom variable) in open http file
  • CodeLens support to add an actionable link to send request
  • Fold/Unfold for request block

Installation

Installing REST Client is straightforward:

  1. Open VS Code
  2. Go to the Extensions marketplace (Ctrl+Shift+X / Cmd+Shift+X)
  3. Search for "REST Client" by Huachao Mao
  4. Click Install

That's it! You're ready to start making API calls.

Creating your first request

Create a new file with the .http or .rest extension. Let's call it example.http:

 

As soon as you save the file, you'll notice a "Send Request" button appears above the GET line. Click it, and voilà! The response appears in a new pane to the right, complete with status code, headers, and body.

Working with multiple requests

Of course you typically want to manage multiple API calls. Separate requests using three hash symbols (###):

Important: Notice the empty line between the headers and the JSON body in the POST request. This blank line is required by the extension.

Adding variables

Define variables at the top of your .http file for values that remain constant throughout:

 

What’s next?

This is only the tip of the iceberg of what is possible with the REST Client extension. there is a lot more to discover. I would recommend giving the extension a try. It transforms VS Code into a capable API testing tool without sacrificing the simplicity and focus that make it a great editor. By keeping your HTTP requests in .http files alongside your code, you create living documentation that your entire team can use and maintain.

Whether you're building a new API, integrating with external services, or just need to quickly test an endpoint, REST Client keeps you in your flow and makes API testing feel like a natural part of your development process.

More information

Use .http files in Visual Studio 2022 | Microsoft Learn

REST Client - Visual Studio Marketplace

Labels:

Popular posts from this blog

Podman– Command execution failed with exit code 125

After updating WSL on one of the developer machines, Podman failed to work. When we took a look through Podman Desktop, we noticed that Podman had stopped running and returned the following error message: Error: Command execution failed with exit code 125 Here are the steps we tried to fix the issue: We started by running podman info to get some extra details on what could be wrong: >podman info OS: windows/amd64 provider: wsl version: 5.3.1 Cannot connect to Podman. Please verify your connection to the Linux system using `podman system connection list`, or try `podman machine init` and `podman machine start` to manage a new Linux VM Error: unable to connect to Podman socket: failed to connect: dial tcp 127.0.0.1:2655: connectex: No connection could be made because the target machine actively refused it. That makes sense as the podman VM was not running. Let’s check the VM: >podman machine list NAME         ...
Read more

Cache stampede: when our cache turned against us

While investigating some performance issues, we ran into an ASP.NET Core API that cached a fairly expensive aggregation query for 60 seconds. Under normal load, that was fine: one request rebuilds the cache, everyone else reads from it. Under peak load, dozens of requests would arrive in that same expiry window, all see a cache miss, and all fire the same expensive query in parallel. The database didn't like that. That was the moment when our caching layer stopped helping and started hurting. A burst of requests comes in at the same time, all miss the cache, and all go hammer the database or the downstream API at once. That's a cache stampede . The cache was supposed to protect our backend, and for a few hundred milliseconds it did the opposite. Why this happens IMemoryCache.GetOrCreate (and its async sibling) looks like it protects you, but it doesn't add any locking on its own. Look at the naive version: public async Task<Report> GetReportAsync(string key) ...
Read more

A complex system designed from scratch never works

A few years ago, I worked as an architect on a big mainframe rewrite. I still count it as one of my failures. Not because the technology was wrong, but because I couldn't convince the management team to simplify the approach. Years later, the organization is still struggling to get the new system up and running. I left the project at the time, because I couldn't put my name behind an approach that would take very long and cost a lot of money without a working system to show for it along the way. Gall’s Law That memory keeps coming back to me, because it's a textbook case of Gall's Law playing out in real life. Gall's Law , from John Gall's Systemantics , states it plainly: A complex system that works is invariably found to have evolved from a simple system that worked. A complex system designed from scratch never works, and it cannot be patched to make it work. You have to start over with a simple system that works. What does that mean in practice,...
Read more