configer.py

import inspect
import os
import sys
import yaml
from yaml.parser import ParserError


def env(env_variable):
    var = os.getenv(env_variable)
    return var if var else ""


def prune_empty(items):
    return list(filter(None, items))


class Sources(object):

    def __init__(self, sources):
        self.source_map = {}
        for source_label, file_path in sources.items():
            self.source_map[source_label] = {
                "data": None,
                "file_path": file_path
            }
            try:
                with open(r'{f}'.format(f=file_path)) as file:
                    try:
                        self.source_map[source_label]["data"] = yaml.load(file, Loader=yaml.FullLoader)
                    except ParserError:
                        print("Error - {f} is Not valid YAML.".format(f=file_path))

            except FileNotFoundError:
                print("Error - {f} No Such File.".format(f=file_path))

    def grab(self, source_label, path):

        if source_label not in self.source_map:
            print("Error - No Source with label {l} exists".format(l=source_label))
            return None

        data = self.source_map[source_label]["data"]
        file_path = self.source_map[source_label]["file_path"]
        dict_path = ''
        for part in path.split('.'):
            dict_path += "[" + part + "]" if part.isdigit() else "['" + part + "']"

        try:
            return eval("data" + dict_path)
        except SyntaxError:
            print("Error - {p} is invalid syntax. Evaluated to {d}".format(p=path, d=dict_path))
            sys.exit(1)
        except KeyError:
            print("Error - {p} does not exist in file: {f}".format(p=path, f=file_path))
            sys.exit(1)
        except IndexError:
            print("Error - {p} index our of range in file: {f}".format(p=path, f=file_path))
            sys.exit(1)


class Files(object):

    def __init__(self, files):
        self.file_map = {}
        for file_label, file_path in files.items():
            self.file_map[file_label] = {
                "text": None,
                "file_path": file_path
            }
            try:
                with open(r'{f}'.format(f=file_path)) as file:
                    self.file_map[file_label]["text"] = file.read()
            except FileNotFoundError:
                print("Error - {f} No Such File.".format(f=file_path))

    def grab(self, file_label):

        if file_label not in self.file_map:
            print("Error - No File with label {l} exists".format(l=file_label))
            return None
        return self.file_map[file_label]["text"]


class Include(object):
    @staticmethod
    def when(expression, if_block, else_block={}):
        return if_block if expression else else_block


def generate(config):
    frame = inspect.stack()[1]
    module = inspect.getmodule(frame[0])
    slash = '\\' if os.name == "nt" else "/"
    filename = module.__file__.split(slash)[-1].replace(".py", "")

    yaml.SafeDumper.org_represent_str = yaml.SafeDumper.represent_str

    def multi_str(dumper, data):
        if '\n' in data:
            return dumper.represent_scalar(
                'tag:yaml.org,2002:str', data, style='|')
        return dumper.org_represent_str(data)
    yaml.add_representer(str, multi_str, Dumper=yaml.SafeDumper)

    with open(filename + ".yml", 'w') as file:
        yaml.SafeDumper.ignore_aliases = lambda *args: True
        yaml.safe_dump(config, file, sort_keys=False, default_flow_style=False)