Inserting values into JS scripts using python

I am parsing JS files stored in a directory to fetch out the values inside tags. Upon finding relevant values in the tags using regex, I want to move those values under a new section called controls. I have been able to get the required values in the controls variable using the script below:

def parse_sigs(target_folder):    
    try:
        count = 0

        for root, dir, files in os.walk(target_folder):
            for file in files:
                file_extension = os.path.splitext(file)[1]
                if file_extension.lower() == ".js":
                    print(file)
                    filename = os.path.join(root, file)
                    print(f'Processing : {filename}')

                    with open(filename, "r") as f_in:
                        data = f_in.read()
                    data = re.search(r"btagss*:s*([.*?])", data, flags=re.S)
                    if data:
                        data = literal_eval(data.group(1))
                        #print(type(data)
                        cregex = re.compile(r".*-.*-.*[.|-].*")
                        controls = list(filter(cregex.match, data))
                            
                        count +=1
                        print(controls)
        print(count)
    except Exception as e:
        print(f"Error in Processing  {filename} Skipping -- ")  
        print(e)  

I am not able to think of a way to now insert the controls list as a new field into the JS file and update it. It should appear after the tags field.

An example JS file looks like:

var fs = require('fs');
var path = require('path')
const remediation = fs.readFileSync(path.resolve(__dirname, '../sig/file.md'), 'utf-8')

module.exports = {
  status: "ENABLED",
  sig: {
    name: "iam",
    tags: [
        "aws",
        "iam",
        "compliance",
        "chg-02.1",
        "AWS-CIS-v1.4",
        "AWS-CIS-v1.4-1.12",
        "AWS-CIS-v1.4-1.14",
        "SOC-2",
        "SOC-2-CC6.8",
        "NIST-800-53rev5",
        "NIST-800-53rev5-CM-3(1)"
    ],
    result: "A.id, A.name",
    result_header: [
      "account_id",
      "account_name",
    ],
    primary_resource: "user_arn",
  },
  expected: {
   "all":
    [
      {
        user_name: "2506"
      }
    ]
  }
};

My end goal is to create a JS file whose tags and newly added controls section looks like this:

    tags: [
        "aws",
        "iam",
        "compliance",
        "chg-02.1",
        "AWS-CIS-v1.4",
        "SOC-2",
        "NIST-800-53rev5"
    ],

controls: [
        "AWS-CIS-v1.4-1.12",
        "AWS-CIS-v1.4-1.14",
        "NIST-800-53rev5-CM-3(1)",
        "SOC-2-CC6.8",
    ],

Edit: Able to get it working with the solution provided by @Dan-Dev. The only thing which is still out of place is the closing ]. Is there a way to fix the closing bracket to indent correctly?

    tags: [
        "aws",
        "docdb",
        "kms",
        "configuration-check",
],
 controls: [
        "SOC-2-CC6.1",
        "NIST-800-53rev5-SC-12"
]

Answer

You can extract the tags and convert them to JSON using the package jsonnet iterate over them using your regex then build a string to replace the original tags like this:

import json
import os
import re
import _jsonnet


def parse_sigs(target_folder):
    
    count = 0
    cregex = re.compile(r".*-.*-.*[.|-].*")
    for root, _, files in os.walk(target_folder):
        for file in files:
            file_extension = os.path.splitext(file)[1]

            if file_extension.lower() == ".js":
                new_tags = []
                controls = []
                # pint(file)

                filename = os.path.join(root, file)
                print(f'Processing : {filename}')
                try:
                    with open(filename, "r") as f_in:
                        data = f_in.read()
                        snippet = re.findall(r'module.exports = (.*);', data, flags=re.S)[0]
                    json_data = json.loads(_jsonnet.evaluate_snippet('snippet', snippet))

                    # print(json.dumps(json_data['sig']['tags'], indent=4))
                    for tag in json_data['sig']['tags']:
                        if re.match(cregex, tag):
                            controls.append(tag)
                        else:
                            new_tags.append(tag)
                    new_string = f"tags: {json.dumps(new_tags, indent=8)},n controls: {json.dumps(controls, indent=8)}"

                    data = re.sub(r'tags: [(.*?)]', new_string, data, flags=re.S)
                    
                    if data:
                        print(data)
                        count += 1
                    print(count)
                    
                except Exception as e:
                    print(f"Error in Processing  {filename} Skipping -- ")
                    print(e)


parse_sigs('./')

Outputs:

Processing : ./test.js
var fs = require('fs');
var path = require('path')
const remediation = fs.readFileSync(path.resolve(__dirname, '../sig/file.md'), 'utf-8')

module.exports = {
  status: "ENABLED",
  sig: {
    name: "iam",
    tags: [
        "aws",
        "iam",
        "compliance",
        "chg-02.1",
        "SOC-2",
        "NIST-800-53rev5"
],
 controls: [
        "AWS-CIS-v1.4",
        "AWS-CIS-v1.4-1.12",
        "AWS-CIS-v1.4-1.14",
        "SOC-2-CC6.8",
        "NIST-800-53rev5-CM-3(1)"
],
    result: "A.id, A.name",
    result_header: [
      "account_id",
      "account_name",
    ],
    primary_resource: "user_arn",
  },
  expected: {
   "all":
    [
      {
        user_name: "2506"
      }
    ]
  }
};


1

UPDATED WITH FORMATTING:

import json
import os
import re
import _jsonnet
import jsbeautifier


opts = jsbeautifier.default_options()
opts.indent_size = 2
opts.space_in_empty_paren = True


def parse_sigs(target_folder):
    count = 0
    cregex = re.compile(r".*-.*-.*[.|-].*")
    for root, _, files in os.walk(target_folder):
        for file in files:
            file_extension = os.path.splitext(file)[1]

            if file_extension.lower() == ".js":
                new_tags = []
                controls = []
                # pint(file)

                filename = os.path.join(root, file)
                print(f'Processing : {filename}')
                try:
                    with open(filename, "r") as f_in:
                        data = f_in.read()
                        snippet = re.findall(r'module.exports = (.*);', data, flags=re.S)[0]
                    json_data = json.loads(_jsonnet.evaluate_snippet('snippet', snippet))

                    # print(json.dumps(json_data['sig']['tags'], indent=4))
                    for tag in json_data['sig']['tags']:
                        if re.match(cregex, tag):
                            controls.append(tag)
                        else:
                            new_tags.append(tag)
                    new_string = f"tags: {json.dumps(new_tags, indent=8)},n controls: {json.dumps(controls, indent=8)}"

                    data = re.sub(r'tags: [(.*?)]', new_string, data, flags=re.S)

                    data = jsbeautifier.beautify(data, opts)

                    if data:
                        print(data)
                        count += 1
                    print(count)

                except Exception as e:
                    print(f"Error in Processing  {filename} Skipping -- ")
                    print(e)


parse_sigs('./')