Help with capturing a specific array slice in jsonpath on Insomnia

[marcobr92]

Hi everyone,

I'm trying to capture a specific slice of an array from an API response using JSONPath in Insomnia, but I haven't been successful so far.

Here’s what I’m trying to achieve: I want to extract a subset of elements from an array in the response. For example, I want to capture elements 40 to 45 from an array named mydata.

Here are some of the JSONPath expressions I’ve tried:

$..mydata[40,45]
$..mydata[40:45]
$..mydata[40:45:1]
Unfortunately, none of these worked. I did notice that using something like $..mydata[40,41,42] returns a list of the specified elements, but I haven’t been able to make a range or slice work.

From my understanding, this should be a valid use case for JSONPath based on references like:

https://goessner.net/articles/JsonPath/index.html#e2
https://github.com/json-path/JsonPath
https://docs.oracle.com/cd/E60058_01/PDF/8.0.8.x/8.0.8.0.0/PMF_HTML/JsonPath_Expressions.htm

Is there a specific syntax or limitation in Insomnia’s JSONPath implementation that I should be aware of? Or is there another way to achieve this?

Any help or guidance would be greatly appreciated!

Thanks in advance!

[poojithap11]

Hi,

I tested this from my end using- $.data.mydata[41:44]

It appears that Insomnia's current implementation shifts both the starting index and last index down by 1 when processing a range.

So for your input: $.data.mydata[41:44]
Insomnia Internally treats the start as 41 - 1 = 40.
Because of this adjustment, the elements returned are - [40, 41, 42].

Is this the issue you're facing on your end?

Thank you.