Exemplo extensão AuthorizerQueryBuilder

gistfile1.txt

using System.Text.RegularExpressions;
using Xgen.Common.Extensions;

namespace Xgen.QueryProcessor.Query
{
    public class AuthorizerQueryBuilder
    {
        #region Private Members
        private static readonly Regex WhereRegex = new Regex(@"where\s+(?=\()(?=((?:(?=.*?\((?!.*?\2)(.*\)(?!.*\3).*))(?=.*?\)(?!.*?\3)(.*)).)+?.*?(?=\2)[^(]*(?=\3$)))", RegexOptions.Compiled | RegexOptions.Multiline | RegexOptions.IgnoreCase);
        #endregion
        
        #region Public Methods
        public static string Create(string query, int userId, int originType, string columnName)
        {
            var singleLineQuery = query.ToSingleLine();
            var matches = WhereRegex.Matches(singleLineQuery);

            var originalCriteria = string.Empty;
            if (matches.Count > 0)
                originalCriteria = matches[matches.Count - 1].Groups[1].Value;

            if (originalCriteria.IsNullOrEmpty())
                return $"{singleLineQuery} where ({Where(userId, originType, columnName)})";

            return singleLineQuery.Replace(originalCriteria, $"({ExtractInnerExpression(originalCriteria)} and {Where(userId, originType, columnName)})");
        }
        #endregion

        #region Private Methods
        private static string ExtractInnerExpression(string originalCriteria)
        {
            return originalCriteria.Substring(1, originalCriteria.LastIndexOf(')')-1);
        }

        protected virtual string Where(int userId, int originType, string columnName)
        {
            return $@"exists (select 1
                                from [user].users __u
                               where (__u.id = {userId}
                                 and (__u.type & 0x02 > 0 or __u.type & 0x04 > 0))

                              union

                             select 1
                               from [user].things __t
                               join [user].users __u
                                 on __t.createdby = __u.id
                              where (__u.type & 0x02 = 0 
                                and __u.type & 0x04 = 0
                                and __t.createdby = {userId}
                                and __t.origintype = {originType} 
                                and __t.originId = {columnName})
                                                
                              union
    
                             select 1
                               from [user].users __u
                               join [user].userrole __ur
                                 on __u.id = __ur.userid
                               join [user].roles __r
                                 on __ur.roleid = __r.id
                               join [user].permissions __p
                                 on __r.id = __p.roleid
                               join [user].things __t
                                 on __p.thingid = __t.id
                              where (__u.type & 0x02 = 0 
                                and __u.type & 0x04 = 0
                                and __u.id = {userId}
                                and __t.origintype = {originType} 
                                and __t.originId = {columnName}))";
        }
        #endregion
    }

    public class Authorizerx : AuthorizerQueryBuilder
    {
        private readonly int _type;

        public Authorizerx(int type)
        {
            _type = type;
        }

        protected override string Where(int userId, int originType, string columnName)
        {
            var query = base.Where(userId, originType, columnName);

            return $"((select case when {_type} != 1 then 1 else 0 end = 1) OR {query})";
        }
    }
}