Postman for load testing using k6, with Tim Haselaars (k6 Office Hours #43)

Tim Haselaars joins Office Hours to talk about how to convert a Postman collection to a k6 load test, the advantages of Postman, and the benefits of reusing automation testing scripts for performance. Tim is a Product Manager at Selligent Marketing Cloud.
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TIMESTAMPS:
0:00 Intro
02:49 Tim's use case for k6
08:05 Quick tour of Postman
14:55 Postman is not designed for load testing
20:07 Demo of postman-to-k6
48:50 How to use Portman to generate tests from an OpenAPI spec
Postman-to-k6 conversion: github.com/apideck-libraries/...
What is Portman: blog.apideck.com/announcing-p...
The Postman collection that Tim was using in this video: www.postman.com/collections/7...
Contact Nicole:
Twitter: / n_vanderhoeven
Site: nicolevanderhoeven.com
GitHub: github.com/nicolevanderhoeven
Contact Tim:
Twitter: / timhaselaars
GitHub: github.com/thim81
Learn more about k6:
Website: k6.io
Repo: github.com/k6io/k6

[@user-tu3ew8yx1q]

this is a golden video.! thank you Tim for sharing your knowledge!

[@Long_Le29]

Thank you Tim and the k6 team for making this. Really mind blowing !!!

[@darinacherepanova6930]

Many thanks for this video! It's really helpful

[@performance_testing]

Thank you guys!

[@NomadicDmitry]

Wow, it's nice to see that there is a script to convert from a Postman script to K6. Nice one!

[@k6io]

Yeah! It's awesome, right?? Tim's definitely doing great work!

[@chakrapani555]

Excellent !!!. Really Mind blowing work. Thank you Tim and K6

[@k6io]

Happy to hear you liked it, Chakrapani! Tim is indeed doing fantastic work! - Nicole

[@pratikshekar1987]

I am speechless after seeing how the API design, development, documentation and test are automated. Pretty excited to try the Postman to k6 integration. Great work :)

[@k6io]

Really love hearing that, Kunal-- I hope you've gotten a chance to try it! We'd love to hear what you think. :) - Nicole

[@joepage3065]

Great presentation, thanks for sharing.

[@k6io]

Thanks for watching!

[@TBVnBIX]

I had the similar experience with postman, where i chained like 20+ requests and tryed to stress test the system at my work with them, but it wasn't enough. Postman was crashing here and there, so i decided to switch to Cypress and K6, with K6 i'm doing stress tests that break the system and it helped a lot for refactoring the code of the backend. Thought i was the only one with such expirience, glad i watched this stream

[@k6io]

It's great to hear this use case! I think Postman is a great tool, but I agree that Cypress and k6 are better for what you needed. Thanks for watching! - Nicole

[@kousiksinha6171]

It is really brilliant and very useful

[@k6io]

Glad you think so!

[@Kpizzle1289]

Love this guys! I want to take this workflow into my QA team. Do you know if the postman-to-k6 supports GraphQL or will it only convert REST API's?

[@k6io]

Hi Kyle! I asked Tim about GraphQL support for the converter, and he mentioned that there is an existing issue that was just raised: github.com/apideck-libraries/postman-to-k6/issues/41 Was it you? In any case, it would be useful if you could chime in on that thread with more information about the error you're seeing. - Nicole

[@nikolayt7246]

Hi! I have question. And help would be greatly appreciated. After running my load tests to the K6 cloud, how can I compare custom metrics between two runs from the Performance Overview section. It seems that my Performance Overview section only contains some default metrics: VUs, request rate, response time and failed requests rate, but I want to add my already generated custom metrics from the Analysis section to the Performance Overview section, so I can use the Compare Result option and compare between two test runs, thanks!

[@k6io]

Hi, Nic! You can't add custom metrics to the Performance Overview section, but if you already have the custom metric added in the Analysis section, you can add click the + sign to "Add to comparison", and it will show up in the comparison chart. If you have further questions, could you reach out to us at [e-mail] ? That way we can have a look at your specific account if needed. :) - Nicole

[@eversondesda6846]

Top

[@abhinayadutta]

Hi, by any chance is there a way to add config.json in the k6 script using postman-to-k6 converter? How can we handle it without touching the k6 script?

[@djthim]

You can pass along the K6 params and the postman-to-k6 convertor will use in the generated K6 script. Have a look at the readme of the postman-to-k6 package and look for the "K6 Param Options File"

[@djthim]

Can you share your issue in the Github issue queue of the library, that makes it easier to figure out what your usecase is.

[@wmorgenstern]

I am using portman to convert from OpenAPI Spec to postman, and then use postman to k6, to run k6. However, when I use postman-to-k6, I get this error GoError: group and check names may not contain '::'

[@valentinadube9867]

How did you export postman collection to IJ? I get blank file.

[@djthim]

What do you mean with IJ?

[@keerthimj8248]

I have converted a Postman collection into K6 Script but I am facing an error TypeError: Cannot read property 'set' of undefined or null pm.test("Login request", function() { pm.environment.set("Authorization", response.headers["AuthToken"]); }); Help me on this - How to do the sequencing

[@djthim]

Can you drop this issue on the discussion board of the repo? That way we can see in the community, how to solve this.

[@forrestthompson4686]

Is there an example of an npx script where a collection and environment is being called from Postman API directly and not calling files living within the repo?

[@djthim]

Hi Forrest Thompson, we have added a small example how to fetch the collection & environment directly from the Postman API: github.com/apideck-libraries/postman-to-k6/discussions/85#discussioncomment-3597827

[@djthim]

hi Thompson, We shared an example in the Github repo > discussions section:" Using PM API key for collection and env" #85

[@billyramogi8864]

How's this free 😀? I'm becoming a Ninja thanks to you

[@k6io]

Haha. Glad to hear it! Open source all the way! :) - Nicole