#input from user (for example)
string = "Apple == 5 & (Plum == 7 | Pear == 8)"

string = string.replace('==', ' eq ')
string = string.replace('<>', ' ne ')
string = string.replace('>' , ' gt ')
string = string.replace('>=', ' ge ')
string = string.replace('<' , ' lt ')
string = string.replace('<=', ' le ')
string = string.replace('&' , ' and ')
string = string.replace('|' , ' or ')
string = string.replace('!=', ' not ')

print(string)
# "Apple eq 5 and (Plum eq 7 or Pear eq 8)"

import pyparsing as pp

    operator = pp.Regex(r">=|<=|!=|>|<|=|eq").setName("operator")
    number = pp.Regex(r"[+-]?\d+(:?\.\d*)?(:?[eE][+-]?\d+)?")
    identifier = pp.Word(pp.alphas, pp.alphanums + "_")
    comparison_term = identifier | number 
    condition = pp.Group(comparison_term("Field") + operator("Operator") + comparison_term("Value"))
    expr = pp.operatorPrecedence(condition("Filters"), [
                                ("and", 2, pp.opAssoc.LEFT, ),
                                ("or", 2, pp.opAssoc.LEFT, ),
                                ("not", 1, pp.opAssoc.RIGHT, ),
                                ]).setResultsName("Filter")

pars = expr.parseString(string).asXML()
   
import xmltodict, json
    o = xmltodict.parse(pars)

    with open("C:\\Users\\palo173\\Desktop\\example.json","w") as f:
        json.dump(o,f)
f.close()

Output:
{
    "Filter": {
        "Filter": {
            "Filters": [
                {
                    "Field": "Apple",
                    "Operator": "eq",
                    "Value": "5"
                },
                {
                    "Filters": [
                        {
                            "Field": "Plum",
                            "Operator": "eq",
                            "Value": "7"
                        },
                        {
                            "Field": "Pear",
                            "Operator": "eq",
                            "Value": "8"
                        }
                    ],
                    "ITEM": "or"
                }
            ],
            "ITEM": "and"
        }
    }
}

Output:
{
                "CategoryId": 0,

                "FilterRequest":
                {

                               "Page": 1,

                               "PageSize": 10,

                               "Filter": 
                               { 
                                   "Logic": "and",

                                   "Filters": [
                                       { 
                                           "Logic": "or",
                                           "Filters": [
                                               { 
                                                   "Field": "Plum",
                                                   "Operator": "eq", 
                                                   "Value": "7"
                                               },
                                               { 
                                                   "Field": "Pear",
                                                   "Operator": "eq", 
                                                   "Value": "8"
                                               }
                                           ]
                                       },
                                       { 
                                           "Field": "Apple",
                                           "Operator": "eq", 
                                           "Value": "5"
                                       }
                                   ]
                               }

                }
}

(May-10-2019, 03:58 PM)Larz60+ Wrote: check this out, similar application: https://stackoverflow.com/a/32975160