I’ve been a long-time user of Postman, and I’ve seen it grow throughout the years. All I need from Postman is a REST client to check my API endpoints. Recently though, as I opened Postman and had to click through three offers for services I will never use, I started thinking that I should take a survey of alternatives with less bloat and take them for a test drive.
Below are the services I found that serve the purpose of simply sending requests to an API among a few the other features that went into consideration were:
- Request History
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- The ability to recall previous requests was second only to sending requests in my priority list while evaluating clients.
- Post Response Testing
- If doing repeated testing against an API having the ability to test the responses via JavaScript in the client can save a lot of time.
- Collections
- To go hand-in-hand with post-response testing, collections are a great way to organize requests if you’re working with multiple APIs, such as I do as a consultant. In previous lives, I worked with only API, so in those cases collections become less important.
Hoppscotch is a simple web-based interface client, with an available Universal Windows app for download. Unfortunately, Hoppscotch does not inherently support local testing, but there is a browser extension that fills the gap. Once I installed that the extension, I found Hoppscotch quite easy to use. It has a minimal interface, which I appreciate opposed to Visual Studio’s cockpit’s-worth of buttons, dropdown menus, and tools that 80% of us only have a vague idea of its purpose. The desktop app even has a “Zen Mode” which removes the text labels from the side menu. (I do this with my phone apps too, my partner has no idea how I’m able to find anything!) Testing in Hoppscotch is accomplished through their own assertion functions and runs only one test script per request. This can make for some difficult test development if you need to test several pieces of the response. Essentially, you’ll need to AND all your test results together, meaning a failing test could leave you scratching your head for a bit. Overall, Hoppscotch fills the role of “just an API client” very well. If you’re doing local testing, you’ll have to deal with the additional setup, and having an extension attached to your browser which your IT security folks may not be a fan of. If you’re willing and able to use the extension, Hoppscotch is a great overall experience. 8/10
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| Hoppscotch.io as a UWP, clean & simple
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| Same as above, but Zen Mode Activate!
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I was turned onto Insomnia by a colleague and as an insomniac myself, I felt I had to give this client a try! Insomnia is one of the more robust clients I test drove. It sits at the cusp of usability and bloat, in my opinion. Insomnia offers a full-featured experience, included my top three priorities: history, collections, and testing. I was quite impressed with Insomnia’s testing feature. Using the Chai API for assertions, I was able to assemble simple tests within seconds. Even given my zero previous experience with Chai, I was able confirm various pieces of the returned data without having to curse once! Any developer that works primarily in the backend, knows exactly what a blissful experience it is not having to curse at your JavaScipt to get it to work can be.
I digress, Insomnia’s testing capabilities extend beyond individual tests and allow you to run an entire suite of tests at once. This feature makes for fantastic regression testing, as you can fire off multiple requests to different endpoints, each getting their own response to run the test script against. If you’re willing to put in the work, Insomnia can even chain requests for testing, taking values for the previous request and supplying them to the next. Insomnia, despite beginning to get into the territory of “features I’ll never use”, is the best well-rounded Postman alternative I encountered during this venture. 9/10
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| Clean, simple, powerful
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| Sweet testing suite!
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Thunder Client is another tool in the Swiss Army knife of development that is VS Code. I **** VS Code, I’m always on the lookout for ways to get more use out of it. So, Thunder Client fits right into my daily use. Thunder Client lacks some of the features that I’ve taken for granted in the previous two clients. It lacks the ability to bulk edit query parameters and does not provide easy GraphQL queries. If those are important to you, maybe Hoppscotch or Insomnia are a better fit for you. That out of the way, Thunder Client supports all my big three wants in a client. Thunder Client’s testing is a simple dropdown query builder. With a few selections, given limited functions, you’re able to quickly put together tests to examine components of the response.
However, if you’re looking to do more advanced testing, again you’ll need to go elsewhere as Thunder Client doesn’t provide access to the JavaScript generated from the dropdown selectors. Thunder Client is a great way to fire off requests if you’ve already got VS Code open and just need to get to that breakpoint to see where that null reference is popping up. I wouldn’t suggest it as a tool to cover all your documentable cases, but it’s a handy debugging tool attached to an application you likely already have open. 7/10
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| Thunder Client in all its glory
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| Simple test generation!
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Honorable Mention
Yet Another API Development Environment (YAADE) is a container-based API client that you can simply pull the container, install a browser extension, and you’re off and running. This brings the convenience of a web-based approach to your local environment. Unfortunately, Yaade does not appear to support testing JavaScript on return at this time. However, it does provide for collections and history. I don’t use containers in my day to day, and I didn’t want to get involved with dealing with containers at this time, so I gave this one a pass. If you use Yaade, or are set up to try it out, post a comment below and let us know how it is!
Disclaimer: The above views and opinions are the author’s alone, and a not endorsed by the covered applications, the author’s employer, or any other associated entity.
