JsonFileUpdater pre-final

.gitignore

@@ -164,6 +164,7 @@ cython_debug/
 
 # Tests
 tests.py
+tests.json
 
 # PyPi
 .pypirc

ufpy/__init__.py

@@ -34,7 +34,7 @@ def new_func(*args, **kwargs):
 UStack = __deprecated("UStack", Stack, '0.2', '0.5')
 
 # Path package
-__path_version__ = '0.1'
+__path_version__ = '0.2'
 from ufpy.path import *
 
 # GitHub package

ufpy/path/__init__.py

@@ -1,2 +1,3 @@
 from ufpy.path.files import *
+from ufpy.path.json_file_updater import *
 from ufpy.path.tools import *

ufpy/path/json_file_updater.py

@@ -0,0 +1,91 @@
+from __future__ import annotations
+
+__all__ = (
+    'JsonFileUpdater',
+)
+
+from typing import Any, Generic, TypeVar
+from ujson import dumps, loads
+
+VT = TypeVar('VT')
+
+class JsonFileUpdater(Generic[VT]):
+    def __init__(self, json_file_path: str, indent: int = 4) -> None:
+        self.path = json_file_path
+        self.indent = indent
+        self.__d: dict[str, VT] | None = None
+
+    def __load(self) -> dict[str, VT]:
+        with open(self.path, encoding='utf-8') as f:
+            r = loads(f.read())
+        return r
+
+    def __write(self, d: dict[str, VT]) -> None:
+        with open(self.path, 'w', encoding='utf-8') as f:
+            f.write(dumps(
+                d,
+                ensure_ascii=False,
+                indent=self.indent
+            ))
+
+    def __get_dict(self, path: str, __dict: dict[str, Any]) -> dict[str, Any]:
+        if not ' / ' in path:
+            return __dict
+        keys = path.split(' / ')[:-1]
+
+        r = __dict
+        for i in keys:
+            r = r[i]
+        return r
+
+    def __getitem__(self, key: str) -> VT:
+        if self.__d == None:
+            d = self.__load()
+        else:
+            d = self.__d
+
+        keys = key.split(' / ')
+
+        return self.__get_dict(key, d)[keys[-1]]
+
+    def __setitem__(self, key: str, value: VT) -> None:
+        if self.__d == None:
+            d = self.__load()
+
+            keys = key.split(' / ')
+
+            r = d
+            for i in keys:
+                r.setdefault(i, {})
+                r = r[i]
+
+            d2 = self.__get_dict(key, d)
+            d2[keys[-1]] = value
+
+            self.__write(d)
+        else:
+            keys = key.split(' / ')
+
+            r = self.__d
+            for i in keys:
+                r.setdefault(i, {})
+                r = r[i]
+
+            d2 = self.__get_dict(key, self.__d)
+            d2[keys[-1]] = value
+    def __enter__(self) -> JsonFileUpdater:
+        self.__d = self.__load()
+        return self
+
+    def __exit__(self, exception_type, exception_value, traceback) -> None:
+        self.__write(self.__d)
+        self.__d = None
+
+    def __repr__(self) -> str:
+        if self.__d == None:
+            return dumps(
+                self.__load(),
+                ensure_ascii=False,
+                indent=self.indent
+            )
+        return repr(self.__d)