Add --allow-words option to CLI for removing blacklisted field names

README.md

@@ -573,6 +573,13 @@ Arguments:
     * **Example**:  `--disable-str-serializable-types float int BooleanString IsoDatetimeString`
     * **Optional**
 
+* `--allow-words` - List of words to remove from the keyword blacklist.
+    By default, field names that clash with Python keywords or built-ins (e.g. `id`, `type`, `hash`, `format`) are
+    renamed by appending `_` (e.g. `id_`). WARNING: reserved keywords may cause syntax errors if you allow them, so be careful with this option.
+    * **Format**: `--allow-words WORD [WORD ...]`
+    * **Example**: `--allow-words id type` — generates `id: int` and `type: str` instead of `id_: int` and `type_: str`
+    * **Optional**
+
 ### Low level API
 
 \-

json_to_models/cli.py

@@ -71,7 +71,8 @@ def __init__(self):
         self.max_literals: int = -1  # --max-strings-literals
         self.merge_policy: List[ModelCmp] = []  # --merge
         self.structure_fn: STRUCTURE_FN_TYPE = None  # -s
-        self.model_generator: Type[GenericModelCodeGenerator] = None  # -f & --code-generator
+        # -f & --code-generator
+        self.model_generator: Type[GenericModelCodeGenerator] = None
         self.model_generator_kwargs: Dict[str, Any] = None
 
         self.argparser = self._create_argparser()
@@ -93,22 +94,25 @@ def parse_args(self, args: List[str] = None):
         disable_unicode_conversion = namespace.disable_unicode_conversion
         self.strings_converters = namespace.strings_converters
         self.max_literals = namespace.max_strings_literals
-        merge_policy = [m.split("_") if "_" in m else m for m in namespace.merge]
+        merge_policy = [
+            m.split("_") if "_" in m else m for m in namespace.merge]
         structure = namespace.structure
         framework = namespace.framework
         code_generator = namespace.code_generator
         code_generator_kwargs_raw: List[str] = namespace.code_generator_kwargs
         dict_keys_regex: List[str] = namespace.dict_keys_regex
         dict_keys_fields: List[str] = namespace.dict_keys_fields
         preamble: str = namespace.preamble
+        allow_words: List[str] = namespace.allow_words
 
         for name in namespace.disable_str_serializable_types:
             registry.remove_by_name(name)
 
-        self.setup_models_data(namespace.model or (), namespace.list or (), parser)
+        self.setup_models_data(namespace.model or (),
+                               namespace.list or (), parser)
         self.validate(merge_policy, framework, code_generator)
         self.set_args(merge_policy, structure, framework, code_generator, code_generator_kwargs_raw,
-                      dict_keys_regex, dict_keys_fields, disable_unicode_conversion, preamble)
+                      dict_keys_regex, dict_keys_fields, disable_unicode_conversion, preamble, allow_words)
 
     def run(self):
         if self.enable_datetime:
@@ -158,14 +162,18 @@ def validate(self, merge_policy, framework, code_generator):
         for m in merge_policy:
             if isinstance(m, list):
                 if m[0] not in self.MODEL_CMP_MAPPING:
-                    raise ValueError(f"Invalid merge policy '{m[0]}', choices are {self.MODEL_CMP_MAPPING.keys()}")
+                    raise ValueError(
+                        f"Invalid merge policy '{m[0]}', choices are {self.MODEL_CMP_MAPPING.keys()}")
             elif m not in self.MODEL_CMP_MAPPING:
-                raise ValueError(f"Invalid merge policy '{m}', choices are {self.MODEL_CMP_MAPPING.keys()}")
+                raise ValueError(
+                    f"Invalid merge policy '{m}', choices are {self.MODEL_CMP_MAPPING.keys()}")
 
         if framework == 'custom' and code_generator is None:
-            raise ValueError("You should specify --code-generator to support custom generator")
+            raise ValueError(
+                "You should specify --code-generator to support custom generator")
         elif framework != 'custom' and code_generator is not None:
-            raise ValueError("--code-generator argument has no effect without '--framework custom' argument")
+            raise ValueError(
+                "--code-generator argument has no effect without '--framework custom' argument")
 
     def setup_models_data(
             self,
@@ -189,7 +197,8 @@ def setup_models_data(
             elif len(model_tuple) == 3:
                 model_name, lookup, path_raw = model_tuple
             else:
-                raise RuntimeError('`--model` argument should contain exactly 2 or 3 strings')
+                raise RuntimeError(
+                    '`--model` argument should contain exactly 2 or 3 strings')
 
             for real_path in process_path(path_raw):
                 iterator = iter_json_file(parser(real_path), lookup)
@@ -208,6 +217,7 @@ def set_args(
             dict_keys_fields: List[str],
             disable_unicode_conversion: bool,
             preamble: str,
+            allow_words: List[str] = (),
     ):
         """
         Convert CLI args to python representation and set them to appropriate object attributes
@@ -234,7 +244,8 @@ def set_args(
         self.model_generator_kwargs = dict(
             post_init_converters=self.strings_converters,
             convert_unicode=not disable_unicode_conversion,
-            max_literals=self.max_literals
+            max_literals=self.max_literals,
+            allow_words=allow_words,
         )
         if code_generator_kwargs_raw:
             for item in code_generator_kwargs_raw:
@@ -245,7 +256,8 @@ def set_args(
                 name, value = item.split("=", 1)
                 self.model_generator_kwargs[name] = value
 
-        self.dict_keys_regex = [re.compile(rf"^{r}$") for r in dict_keys_regex] if dict_keys_regex else ()
+        self.dict_keys_regex = [re.compile(
+            rf"^{r}$") for r in dict_keys_regex] if dict_keys_regex else ()
         self.dict_keys_fields = dict_keys_fields or ()
         if preamble:
             preamble = preamble.strip()
@@ -392,6 +404,15 @@ def _create_argparser(cls) -> argparse.ArgumentParser:
             nargs=3, action="append", metavar=("<Model name>", "<JSON lookup>", "<JSON file>"),
             help="DEPRECATED, use --model argument instead"
         )
+        parser.add_argument(
+            "--allow-words",
+            metavar="WORD",
+            default=[],
+            nargs="+", type=str,
+            help="List of words to remove from the keyword blacklist.\n"
+                 "Prevents appending '_' to these field names.\n"
+                 "WARNING: reserved keywords may cause syntax errors if you allow them, so be careful with this option."
+        )
 
         return parser
 
@@ -421,7 +442,8 @@ def json(path: Path) -> Union[dict, list]:
     @staticmethod
     def yaml(path: Path) -> Union[dict, list]:
         if yaml_load is None:
-            print('Yaml parser is not installed. To parse yaml files ruamel.yaml (or PyYaml) is required.')
+            print(
+                'Yaml parser is not installed. To parse yaml files ruamel.yaml (or PyYaml) is required.')
             raise ImportError('yaml')
         with path.open() as fp:
             return yaml_load(fp)
@@ -467,7 +489,8 @@ def iter_json_file(data: Union[dict, list], lookup: str) -> Generator[Union[dict
     elif isinstance(item, dict):
         yield item
     else:
-        raise TypeError(f'dict or list is expected at {lookup if lookup != "-" else "JSON root"}, not {type(item)}')
+        raise TypeError(
+            f'dict or list is expected at {lookup if lookup != "-" else "JSON root"}, not {type(item)}')
 
 
 def process_path(path: str) -> Iterable[Path]:

json_to_models/models/base.py

@@ -24,8 +24,10 @@
 keywords_set = set(keyword.kwlist)
 builtins_set = set(__builtins__.keys())
 other_common_names_set = {'datetime', 'time', 'date', 'defaultdict', 'schema'}
-blacklist_words = frozenset(keywords_set | builtins_set | other_common_names_set)
-ones = ['', 'one', 'two', 'three', 'four', 'five', 'six', 'seven', 'eight', 'nine']
+blacklist_words = frozenset(
+    keywords_set | builtins_set | other_common_names_set)
+ones = ['', 'one', 'two', 'three', 'four',
+        'five', 'six', 'seven', 'eight', 'nine']
 
 
 def template(pattern: str, indent: str = INDENT) -> Template:
@@ -73,7 +75,8 @@ class {{ name }}{% if bases %}({{ bases }}){% endif %}:
 
     STR_CONVERT_DECORATOR = template("convert_strings({{ str_fields }}{%% if kwargs %%}, %s{%% endif %%})"
                                      % KWAGRS_TEMPLATE)
-    FIELD: Template = template("{{name}}: {{type}}{% if body %} = {{ body }}{% endif %}")
+    FIELD: Template = template(
+        "{{name}}: {{type}}{% if body %} = {{ body }}{% endif %}")
     DEFAULT_MAX_LITERALS = 10
     default_types_style = {
         StringLiteral: {
@@ -87,29 +90,36 @@ def __init__(
             max_literals=DEFAULT_MAX_LITERALS,
             post_init_converters=False,
             convert_unicode=True,
-            types_style: Dict[Union['BaseType', Type['BaseType']], dict] = None
+            types_style: Dict[Union['BaseType',
+                                    Type['BaseType']], dict] = None,
+            allow_words: Iterable[str] = (),
     ):
         self.model = model
         self.post_init_converters = post_init_converters
         self.convert_unicode = convert_unicode
+        self.allow_words = frozenset(allow_words)
 
         resolved_types_style = copy.deepcopy(self.default_types_style)
         types_style = types_style or {}
         for t, style in types_style.items():
             resolved_types_style.setdefault(t, {})
             resolved_types_style[t].update(style)
-        resolved_types_style[StringLiteral][StringLiteral.TypeStyle.max_literals] = int(max_literals)
+        resolved_types_style[StringLiteral][StringLiteral.TypeStyle.max_literals] = int(
+            max_literals)
         self.types_style = resolved_types_style
 
-        self.model.set_raw_name(self.convert_class_name(self.model.name), generated=self.model.is_name_generated)
+        self.model.set_raw_name(self.convert_class_name(
+            self.model.name), generated=self.model.is_name_generated)
 
     @cached_method
     def convert_class_name(self, name):
-        return prepare_label(name, convert_unicode=self.convert_unicode, to_snake_case=False)
+        return prepare_label(name, convert_unicode=self.convert_unicode, to_snake_case=False,
+                             allow_words=self.allow_words)
 
     @cached_method
     def convert_field_name(self, name):
-        return prepare_label(name, convert_unicode=self.convert_unicode, to_snake_case=True)
+        return prepare_label(name, convert_unicode=self.convert_unicode, to_snake_case=True,
+                             allow_words=self.allow_words)
 
     def generate(self, nested_classes: List[str] = None, bases: str = None, extra: str = "") \
             -> Tuple[ImportPathList, str]:
@@ -142,9 +152,11 @@ def decorators(self) -> Tuple[ImportPathList, List[str]]:
             if str_fields and decorator_kwargs:
                 imports.extend([
                     *decorator_imports,
-                    ('json_to_models.models.string_converters', ['convert_strings']),
+                    ('json_to_models.models.string_converters',
+                     ['convert_strings']),
                 ])
-                decorators.append(self.STR_CONVERT_DECORATOR.render(str_fields=str_fields, kwargs=decorator_kwargs))
+                decorators.append(self.STR_CONVERT_DECORATOR.render(
+                    str_fields=str_fields, kwargs=decorator_kwargs))
         return imports, decorators
 
     def field_data(self, name: str, meta: MetaData, optional: bool) -> Tuple[ImportPathList, dict]:
@@ -156,7 +168,8 @@ def field_data(self, name: str, meta: MetaData, optional: bool) -> Tuple[ImportP
         :param optional: Is field optional
         :return: imports, field data
         """
-        imports, typing = metadata_to_typing(meta, types_style=self.types_style)
+        imports, typing = metadata_to_typing(
+            meta, types_style=self.types_style)
 
         data = {
             "name": self.convert_field_name(name),
@@ -171,13 +184,15 @@ def fields(self) -> Tuple[ImportPathList, List[str]]:
 
         :return: imports, list of fields as string
         """
-        required, optional = sort_fields(self.model, unicode_fix=not self.convert_unicode)
+        required, optional = sort_fields(
+            self.model, unicode_fix=not self.convert_unicode)
         imports: ImportPathList = []
         strings: List[str] = []
         for is_optional, fields in enumerate((required, optional)):
             fields = self._filter_fields(fields)
             for field in fields:
-                field_imports, data = self.field_data(field, self.model.type[field], bool(is_optional))
+                field_imports, data = self.field_data(
+                    field, self.model.type[field], bool(is_optional))
                 imports.extend(field_imports)
                 strings.append(self.FIELD.render(**data))
         return imports, strings
@@ -256,7 +271,8 @@ def generate_code(structure: ModelsStructureType, class_generator: Type[GenericM
     """
     root, mapping = structure
     with AbsoluteModelRef.inject(mapping):
-        imports, classes = _generate_code(root, class_generator, class_generator_kwargs or {})
+        imports, classes = _generate_code(
+            root, class_generator, class_generator_kwargs or {})
         imports_str = ""
     if imports:
         imports_str = compile_imports(imports) + objects_delimiter
@@ -284,7 +300,8 @@ def sort_kwargs(kwargs: dict, ordering: Iterable[Iterable[str]]) -> dict:
     return sorted_dict
 
 
-def prepare_label(s: str, convert_unicode: bool, to_snake_case: bool) -> str:
+def prepare_label(s: str, convert_unicode: bool, to_snake_case: bool,
+                  allow_words: frozenset = frozenset()) -> str:
     if convert_unicode:
         s = unidecode(s)
     s = re.sub(r"\W", "", s)
@@ -293,6 +310,6 @@ def prepare_label(s: str, convert_unicode: bool, to_snake_case: bool) -> str:
             s = ones[int(s[0])] + "_" + s[1:]
     if to_snake_case:
         s = inflection.underscore(s)
-    if s in blacklist_words:
+    if s in (blacklist_words - allow_words):
         s += "_"
     return s