Processing escaped url strings within json using python

Question

I am accessing a service that is returning json as follows:

{
"A":"A value",
"B":{
      "B1":"B1 value",
      "B2":"B2 value"
    },
"C":{
               "c_url":"http:\/\/someurl:someport\/somefolder\/somefile",

    }
}

What I want to do is parse this json and get the url and the somefile portion of the folder in a key-value pair.

So, essentially, after my script is done processing the json, it will output the url and the somefile in some delimited fashion in a file.

The output after the file has processed the above provided json would be:

url: http://someurl:someport/somefolder/somefile
file: somefile

I am pretty sure there are numerous json parsers in python that will parse the json but how would I deal with the url string that has been pre-processed with escape characters? Do I need to write my own url-encoder that will strip out the escape characters from the url string?

Also, I would need to tokenize the individual components of the url to get to the 'file' portion, are there any libraries that can help with that?

Thanks

Something like http://stackoverflow.com/questions/1885181/how-do-i-un-escape-a-backslash-escaped-string-in-python would help? — favoretti, Aug 09 '12 at 21:28
It seems that particular thing doesn't help but I stumbled on something else. http://www.quora.com/Why-does-the-cjson-Python-module-not-correctly-unescape-reverse-solidus-solidus — favoretti, Aug 09 '12 at 21:32
There is no need to do anything besides using a normal JSON parser. `\/` is a valid way to encode `/` within a string in JSON, and every conforming JSON parser will convert it. — Karl Knechtel, Aug 05 '22 at 03:32

score 2 · Answer 1 · answered Aug 09 '12 at 21:35

So, as per http://www.quora.com/Why-does-the-cjson-Python-module-not-correctly-unescape-reverse-solidus-solidus

simplejson should be able to handle this "buggy" escaping algorithm. Consider:

#!/usr/bin/env python
import simplejson

print simplejson.loads('"http:\/\/someurl:someport\/somefolder\/somefile"')

Note, that simplejson is not a standard package, but is installable via easy_install.

Sample output:

[85][23:35:24] vlazarenko@alluminium (~/tests) > python unescape.py 
http://someurl:someport/somefolder/somefile

Brenden Brown · Accepted Answer · 2012-08-09T22:03:56.773

Your example JSON doesn't need the comma after the "c_url" k-v pair.

>>> import json
>>> st = '{"A":"A value","B":{ "B1":"B1 value", "B2":"B2 value" },"C":{ "c
_url":"http:\/\/someurl:someport\/somefolder\/somefile" }}'
>>> json.loads(st)
{u'A': u'A value', u'C': {u'c_url': u'http://someurl:someport/somefolder/somefile'}, u'B': {u'B1': u
'B1 value', u'B2': u'B2 value'}}

And to get just the 'somefile' part of the URL:

url.split('/')[url.count('/')]

Processing escaped url strings within json using python

2 Answers2