nagrest/lib/nag_parse.py

#!/usr/bin/env python3
import re
import json
import hashlib
from enum import Enum, auto
from .nag_object import NagObject, NagObjectType

class ParserState(Enum):
    COMMENT = auto()
    DEFINE = auto()
    DIRECTIVE = auto()
    MULTILINE = auto()

def hash_string(string:str) -> int:
    hash = hashlib.sha256()
    hash.update(string.encode('utf-8'))
    digest = hash.hexdigest()
    return int(digest,16) * 1000000

class NagParse:
    def __init__(self):
        self.m_config_table: dict[int,str] = dict()
        self.m_objects: list[NagObject] = list()


    def __str__(self):
        string = str()
        for object in self.m_objects:
            string += str(object) + "\n"
        return string

    def consume_config_files(self, config_files: list[str]) -> None:
        for config_file in config_files:
            self.m_config_table[hash_string(config_file)] = config_file
            for object in self.parse_config(config_file):
                self.m_objects.append(object)

    def consume_config_list(self, config_list: list[dict] ) -> None:
        for object in config_list:
            nag_object = NagObject()
            nag_object.from_object(object)
            self.m_objects.append(nag_object)

    def to_json(self):
        return json.dumps([x.to_object() for x in self.m_objects])

    def parse_config(self,config_file: str) -> list[NagObject]:
        state = ParserState.DEFINE
        objects: list[NagObject] = list()
        with open(config_file, 'r') as file_handle:
            line_no = 0
            cur_object = NagObject(config_file=config_file)
            for rawline in file_handle.readlines():
                # Clean up the config
                line = re.sub(r'([a-z]){', r'\1 {',rawline.strip())
                #line = re.sub(r'([a-zA-Z0-9])}', r'\1\n}',line.strip())
                #line = re.sub(r'([a-zA-Z0-9]) }', r'\1\n}',line.strip())
                line_no += 1
                # This means it is a comment, we might want to save those later on
                if len(line) == 0 or re.match('^[\t ]*[#]+', line):
                    continue
                # This means we are done parsing and should reset for new object
                if re.match(r'}', line):
                    objects.append(cur_object)
                    del cur_object
                    state = ParserState.DEFINE
                    continue
                #if we get here it is not a comment and not the end of an object 
                fragments: list[str] = re.sub(' +', ' ', line.strip()).split()

                # This is a new object and we should see what type it is, and what line number it is on
                if state == ParserState.DEFINE:
                    if fragments[0] == 'define':
                        cur_object = NagObject(config_file=config_file, directives=list())
                        cur_object.m_line_no = line_no
                        cur_object.m_type = NagObjectType(fragments[1])
                        # For the next line we should be in DIRECTIVE state
                        state = ParserState.DIRECTIVE
                    else:
                        print("It's fucked up man")
                        break
                # This is the DIRECTIVE state, where we want to collect key, values and find out if we should go to multiline mode
                elif state == ParserState.DIRECTIVE:
                    if fragments[-1][-1] == '\\':
                        state = ParserState.MULTILINE
                    if re.match('^[a-z]+', fragments[0]):
                        cur_object.m_directives.append(
                            [fragments[0], " ".join(fragments[1:])])
                # This is the MULTILINE state, directives can be on many lines if the '\n' is escaped with '\'
                elif state == ParserState.MULTILINE:
                    cur_object.m_directives[-1][1] = cur_object.m_directives[-1][1].strip('\\') + ' ' + " ".join(fragments) 
                    if fragments[-1][-1] != '\\':
                        state = ParserState.DIRECTIVE
                else:
                    print("It's fucked up man")
                    break
        return objects