Implemented update method on most JSONPath descendents. Tests included.

[joshbenner]

Mostly addresses #21. I didn't add update() implementations for Parent, Union, or Intersect, as I wasn't sure it made sense to do so. More esoteric test cases might be good, too, as I'm not 100% sure the implementations work as expected at all times.

[mgcdanny]

Is there a reason why this hasn't been merged in to the master branch?

[mgcdanny]

@joshbenner
Either I am doing something wrong or I found a bug with this pull request. Check out this example:

from jsonpath_rw import parse
jsonpath_expr = parse('$..baz')
data = {'foo': [{'baz': 1}, {'baz': 2}]}
jsonpath_expr.update(data, '1234')
assert data == {'foo': [{'baz': 1234}, {'baz': 1234}]}

[kennknowles]

At a high level, I'd kind of like to reserve the word update for creating a copy with new values in certain places, and call this set, but I like this. It was even my original intent with the library, but I got too busy. I will be happy with whatever name is more Pythonic.

[kennknowles]

More tests, such as those with lists within dictionaries and vice versa, would be nice.

[ailjushkin]

I believe it is very handy PR, can anyone tell me what is needed to merge it?

[jonathanglima]

+1

this will also update passing lambdas instead of the value? if not, that's a great enhancement

[ailjushkin]

Should we believe this PR could be aprooved?

[carpnick]

+1

[cliffpracht]

+1. Useful feature.

[carlosmmelo]

+1

[quazar0]

Thanks for this update. BTW, does this allow removal of a selected element?

[shuaiyuancn]

I'm seeing NotImplementedError:

from jsonpath_rw.parser import parse
parse('$.a').update({'a': 1}, 2)

---------------------------------------------------------------------------
NotImplementedError                       Traceback (most recent call last)
<ipython-input-59-940582069d38> in <module>()
      1 from jsonpath_rw.parser import parse
----> 2 parse('$.a').update({'a': 1}, 2)

/databricks/python/local/lib/python2.7/site-packages/jsonpath_rw/jsonpath.pyc in update(self, data, val)
     28     def update(self, data, val):
     29         "Returns `data` with the specified path replaced by `val`"
---> 30         raise NotImplementedError()
     31 
     32     def child(self, child):

NotImplementedError: 

[GusBricker]

The reason you are getting the NotImplementedError is because the current version (1.4.0) on PyPi predates this pull request.

[namratha-bharadwaj]

Hello... I see the "raise NotImplementedError(), NotImplementedError" when I tried using the update method to change json elements. Is there a work-around for this?

[srhopkins]

Are the plans to cut a new release soon with the update feature?

[kennknowles]

It has been so long since I did a pypi release I don't remember how ;_;