Flatten JSON document to single line

Question

Context: An API I'm integrating spits out data in pretty print form like below. I have a MSSQL parsing proc that requires the input JSON to have a flat form in a single line (tabs removed).

Question: I've found some semi-related questions here & here but they dont seem to address my needs because I dont want to perform operations on the file level.

Can anyone recommend some specific methods for transforming the JSON text into a single line in a more granular fashion? Perhaps regular expressions or some string manipulation methods?

Current JSON form:

{
  "data": {
    "first_name": "Eric",
    "last_name": "B",
    "email": null,
    "score": null,
    "domain": "@datashiftlabs.io",
    "position": null,
    "twitter": null,
    "linkedin_url": null,
    "phone_number": null,
    "company": null,
    "sources": []
  },
  "meta": {
    "params": {
      "first_name": "Eric",
      "last_name": "B",
      "full_name": null,
      "domain": "@datashiftlabs.io",
      "company": null
    }
  }
}

Desired form:

{"data": {"first_name": "Eric","last_name": "B","email": null,"score": null,"domain": "datashiftlabs.io","position": null,"twitter": null,"linkedin_url": null,"phone_number": null,"company": null,"sources": []},"meta": {"params": {"first_name": "Eric","last_name": "B","full_name": null,"domain": "datashiftlabs.io","company": null}}}

Answer 1

I'm not sure if that's actually what you want, but you could convert your json string with the json library to an object, and than convert it back to a string.

The example would look like this

import json

json_str = """{
  "data": {
    "first_name": "Eric",
    "last_name": "B",
    "email": null,
    "score": null,
    "domain": "@datashiftlabs.io",
    "position": null,
    "twitter": null,
    "linkedin_url": null,
    "phone_number": null,
    "company": null,
    "sources": []
  },
  "meta": {
    "params": {
      "first_name": "Eric",
      "last_name": "B",
      "full_name": null,
      "domain": "@datashiftlabs.io",
      "company": null
    }
  }
}"""

obj = json.loads(json_str)
flatten_str = json.dumps(obj)

print(flatten_str)

An alternativ would be using string replace and regex substitution to remove all unnecessary characters like line-breaks, multiple spaces and tabs. A quick draft for this function would look like this. Note: The current regex does not work flawlessly and still has some unintended behavior on certain edge cases, e.g. multiple whitespaces at the end of a string

import re

def flatten_json(string):
    # Remove line breaks
    string = string.replace("\n", "")
    # Remove tabs and multiple spaces
    string = re.sub('[\t ]+("|{|})', r' \1', string)
    # Return result
    return string