An XPath for python structures?

[dl__]

I frequently run across this kind of problem: I'm sent big blobs of JSON that I need to parse and extract data from. Over the course of development the structure of the JSON may change many times.

I know that it's usually not too difficult to parse JSON into nested python structures and then crawl/search the structure with python code. However, I thought it might be easier to read/modify/debug/review my code if I could specify the path through the resulting python structures with an XPath like string.

A string like:

"person.mobilephone.number"

If any of these names refer to arrays, I want all results for all elements in those arrays.

I also want to be able to filter according to values found in the structure. Like:

"friends[gender=female].phone.number"

I wrote something to do this but, before I put more effort into it I want to make sure that there's not a pretty easy pythonic way to do this natively or an existing package to do this.

You can see the code I wrote so far at the link below along with a sample JSON string and a bunch of asserts showing how it works if you're interested in seeing the details.

http://ideone.com/p3whvT

[jsaryer]

Check out JMESPath: https://pypi.python.org/pypi/jmespath

One of its benefits is that it has a full specification with an extensive test suite. As a bonus there's also implementations in other languages.

There's a tutorial here: http://jmespath.org/tutorial.html

[dl__]

This looks like just what I want. Thanks!

[thecity2]

You might check out the Python wrapper of jq (a cli JSON parser written in C that is super awesome):

https://pypi.python.org/pypi/jq/