I am a fan of Insomnia. As far as I can tell it has most of the features I used in postman without all the paid upgrade nags

xh and tiny shell scripts.

Example: sign-up-forbidden-username.req

#!/bin/bash
xh POST http://0.0.0.0:2884/sign-up usename=admin password=pw

to run ./sign-up-forbidden-username.req

This returns 403 and “Username is unavailable”

https://github.com/ducaale/xh

xh is a rust implementation of httpie. They’re going for full parity, and works really well for what I need it for so far You can also read input from a file. Which IMO makes GUI API testing seem silly.

Insomnia is pretty cool and open-source

Insomnia is great and has an easy, simple interface. But I feel like creating complex collections with different environments is a lot simpler with postman

I completely stopped using all those clients. We now just store the requests alongside the code in an http file and use the built in IntelliJ HTTP Client to make the call. No need for a separate program, integrates with your code, you can save responses to make sure they don’t change, it’s all stored in git. There’s a ton of benefits and not many downsides.

Yeah it’s called curl lol

If you’re not strictly looking for GUI tools, you might want to look into httpie or the http command built into the nu shell.

I use Hurl. Everything is just a text file:

POST https://example.org/api/tests
{
    "id": "4568",
    "evaluate": true
}

HTTP 200
[Asserts]
header "X-Frame-Options" == "SAMEORIGIN"
jsonpath "$.status" == "RUNNING"    # Check the status code
jsonpath "$.tests" count == 25      # Check the number of items
jsonpath "$.id" matches /\d{4}/     # Check the format of the id

I recommend Visual Studio Code and one of the following two extensions:

• Thunder Client
• REST Client

Either one isn’t really the full picture - you’ll ned to combine it with other extensions - such as a good JSON language extension (which will give you syntax highlighting, error checking, code folding/etc.

The most important extension is CoPilot. That’s the killer feature which makes Visual Studio Code vastly better than Postman.

Thunder is very similar to Postman. Not much to say other than it works well, it’s free, millions of people use it.

It’s not really my cup of tea, but I do think it’s better than Postman because you can use your own version control servers to collaborate with colleagues, which is generally better (and cheaper) than Postman’s collaboration service in my opinion (you get diffs, code review, pull requests, history, etc etc for all your most important API tests).

Personally I prefer REST Client (also free, and has even more users than Thunder).

REST Client is really simple. It adds a new “HTTP” text file type. You simply type a HTTP request into the file and hit a hotkey (or click a button) to execute the request. And it shows you the response. Easy.

HTTP requests and responses are just plain text, and you can simply save those as files in your project. REST Client also has basic support for variables, API credentials, etc. Not quite as user friendly as Postman or Thunder Client, but it makes up for that by being straightforward and flexible.

CoPilot Chat, works with both, but having everything in plain text gives it more control over REST Client than Thunder Clinet you can write (and edit) your requests with a series of simple plain english prompts. E.g. “JSON request with a blog post body” will give you:

POST https://example.com/blog/posts
Content-Type: application/json

{
    "title": "My First Blog Post",
    "body": "This is the content of my first blog post. It's not very long, but it's a start!",
    "author": "John Doe",
    "tags": ["blogging", "first post"]
}

You might follow that up with “Add a UUID” or “Add a JWT auth header”.

Copilot can answer questions too - e.g. “How do I unsubscribe a user with the Mailchimp API?” They use the “HTTP PATCH” request type - WTF.

Maybe try Swagger

I would use swagger in some instance tbh

I mostly use the rest client extension for vscode

I’m using the vscode extension called Thunderclient

I mostly use httpie on the fish shell with autocompletion for quick requests, but it’s no replacement

Insomnia, or if you really love the command line and dont need to document or save your API requests, curl (don’t recommend this for anything beyond simple testing).