chore(elementsinteractive#153): Use FileHandler in ConfigHandler

Author: Daniel Sanz

src/twyn/config/config_handler.py

@@ -1,8 +1,6 @@
 import logging
 from dataclasses import asdict, dataclass
 from enum import Enum
-from os import getcwd
-from pathlib import Path
 from typing import Optional
 
 from tomlkit import TOMLDocument, dumps, parse, table
@@ -18,6 +16,8 @@
     AllowlistPackageDoesNotExistError,
     TOMLError,
 )
+from twyn.file_handler.exceptions import PathNotFoundError
+from twyn.file_handler.file_handler import FileHandler
 
 logger = logging.getLogger("twyn")
 
@@ -47,8 +47,9 @@ class ReadTwynConfiguration:
 class ConfigHandler:
     """Manage reading and writing configurations for Twyn."""
 
-    def __init__(self, file_path: Optional[str] = None, enforce_file: bool = True):
-        self._file_path = file_path or DEFAULT_PROJECT_TOML_FILE
+    def __init__(self, file_path: Optional[str] = None, enforce_file: bool = True) -> None:
+        file_path = file_path or DEFAULT_PROJECT_TOML_FILE
+        self.file_handler = FileHandler(file_path)
         self._enforce_file = enforce_file
 
     def resolve_config(
@@ -119,36 +120,19 @@ def _write_config(self, toml: TOMLDocument, config: ReadTwynConfiguration) -> No
         if "twyn" not in toml["tool"]:  # type: ignore[operator]
             toml["tool"]["twyn"] = {}  # type: ignore[index]
         toml["tool"]["twyn"] = twyn_toml_data  # type: ignore[index]
+
         self._write_toml(toml)
 
+    def _write_toml(self, toml: TOMLDocument) -> None:
+        self.file_handler.write(dumps(toml))
+
     def _read_toml(self) -> TOMLDocument:
         try:
-            fp = self._get_toml_file_pointer()
-        except FileNotFoundError:
-            if not self._enforce_file and self._file_path == DEFAULT_PROJECT_TOML_FILE:
+            return parse(self.file_handler.read())
+        except PathNotFoundError:
+            if not self._enforce_file and self.file_handler.is_handler_of_file(DEFAULT_PROJECT_TOML_FILE):
                 return TOMLDocument()
-            raise TOMLError(f"Error reading toml from {self._file_path}") from None
-
-        with open(fp, "r") as f:
-            content = parse(f.read())
-        return content
-
-    def _get_toml_file_pointer(self) -> Path:
-        """Create a path for the toml file with the format <current working directory>/self.file_path."""
-        fp = Path(getcwd()) / Path(self._file_path)
-
-        if not fp.is_file():
-            raise FileNotFoundError(f"File not found at path '{fp}'.")
-
-        return fp
-
-    def _write_toml(self, toml: TOMLDocument) -> None:
-        with open(self._get_toml_file_pointer(), "w") as f:
-            try:
-                f.write(dumps(toml))
-            except Exception:
-                logger.exception("Error writing toml file")
-                raise TOMLError(f"Error writing toml to {self._file_path}") from None
+            raise TOMLError(f"Error reading toml from {self.file_handler.file_path}") from None
 
 
 def _get_logging_level(

src/twyn/dependency_parser/abstract_parser.py

@@ -3,7 +3,7 @@
 from abc import ABC, abstractmethod
 from pathlib import Path
 
-from twyn.file_handler.file_handler import FileHandlerPathlib
+from twyn.file_handler.file_handler import FileHandler
 
 logger = logging.getLogger("twyn")
 
@@ -17,7 +17,7 @@ class AbstractParser(ABC):
 
     def __init__(self, file_path: str) -> None:
         self.file_path = Path(os.path.abspath(os.path.join(os.getcwd(), file_path)))
-        self.file_handler = FileHandlerPathlib(file_path=self.file_path)
+        self.file_handler = FileHandler(file_path=self.file_path)
 
     def __str__(self) -> str:
         return self.__class__.__name__

src/twyn/file_handler/file_handler.py

@@ -10,14 +10,20 @@
 
 
 class BaseFileHandler(Protocol):
-    def __init__(self, file_path: str) -> None: ...
     def read(self) -> str: ...
     def file_exists(self) -> bool: ...
+    def write(self, data: str) -> None: ...
 
 
-class FileHandlerPathlib(BaseFileHandler):
+class FileHandler(BaseFileHandler):
     def __init__(self, file_path: str) -> None:
-        self.file_path = Path(os.path.abspath(os.path.join(os.getcwd(), file_path)))
+        self.file_path = self._get_file_path(file_path)
+
+    def _get_file_path(self, file_path: str) -> Path:
+        return Path(os.path.abspath(os.path.join(os.getcwd(), file_path)))
+
+    def is_handler_of_file(self, name: str) -> bool:
+        return self._get_file_path(name) == self.file_path
 
     def read(self) -> str:
         self._raise_for_file_exists()
@@ -40,3 +46,7 @@ def _raise_for_file_exists(self) -> None:
 
         if not self.file_path.is_file():
             raise PathIsNotFileError
+
+    def write(self, data: str) -> None:
+        self._raise_for_file_exists()
+        self.file_path.write_text(data)

tests/core/test_config_handler.py

@@ -11,19 +11,20 @@
     AllowlistPackageDoesNotExistError,
     TOMLError,
 )
+from twyn.file_handler.exceptions import PathNotFoundError
 
 
 class TestConfig:
     def throw_exception(self):
-        raise FileNotFoundError
+        raise PathNotFoundError
 
-    @patch("twyn.config.config_handler.ConfigHandler._get_toml_file_pointer")
+    @patch("twyn.file_handler.file_handler.FileHandler.read")
     def test_enforce_file_error(self, mock_is_file):
         mock_is_file.side_effect = self.throw_exception
         with pytest.raises(TOMLError):
             ConfigHandler(enforce_file=True).resolve_config()
 
-    @patch("twyn.config.config_handler.ConfigHandler._get_toml_file_pointer")
+    @patch("twyn.file_handler.file_handler.FileHandler.read")
     def test_no_enforce_file_on_non_existent_file(self, mock_is_file):
         """Resolving the config without enforcing the file to be present gives you defaults."""
         mock_is_file.side_effect = self.throw_exception
@@ -49,10 +50,10 @@ def test_read_config_values(self, pyproject_toml_file):
         assert config.allowlist == {"boto4", "boto2"}
 
     def test_get_twyn_data_from_file(self, pyproject_toml_file):
-        handler = ConfigHandler(file_path=pyproject_toml_file)
+        handler = ConfigHandler(pyproject_toml_file)
 
         toml = handler._read_toml()
-        twyn_data = ConfigHandler(file_path=pyproject_toml_file)._get_read_config(toml)
+        twyn_data = ConfigHandler(pyproject_toml_file)._get_read_config(toml)
         assert twyn_data == ReadTwynConfiguration(
             dependency_file="my_file.txt",
             selector_method="my_selector",
@@ -62,7 +63,7 @@ def test_get_twyn_data_from_file(self, pyproject_toml_file):
         )
 
     def test_write_toml(self, pyproject_toml_file):
-        handler = ConfigHandler(file_path=pyproject_toml_file)
+        handler = ConfigHandler(pyproject_toml_file)
         toml = handler._read_toml()
 
         initial_config = handler.resolve_config()
@@ -103,12 +104,12 @@ def test_write_toml(self, pyproject_toml_file):
 
 
 class TestAllowlistConfigHandler:
-    @patch("twyn.config.config_handler.ConfigHandler._write_toml")
+    @patch("twyn.file_handler.file_handler.FileHandler.write")
     @patch("twyn.config.config_handler.ConfigHandler._read_toml")
     def test_allowlist_add(self, mock_toml, mock_write_toml):
         mock_toml.return_value = TOMLDocument()
 
-        config = ConfigHandler()
+        config = ConfigHandler("some-file")
 
         config.add_package_to_allowlist("mypackage")
 

tests/file_handler/test_file_handler.py

@@ -2,24 +2,24 @@
 
 import pytest
 from twyn.file_handler.exceptions import PathIsNotFileError, PathNotFoundError
-from twyn.file_handler.file_handler import FileHandlerPathlib
+from twyn.file_handler.file_handler import FileHandler
 
 
-class TestFileHandlerPathlib:
+class TestFileHandler:
     def test_file_exists(self, pyproject_toml_file: str):
-        parser = FileHandlerPathlib(pyproject_toml_file)
+        parser = FileHandler(pyproject_toml_file)
         assert parser.file_exists() is True
 
     def test_read_file_success(self, pyproject_toml_file: str):
-        parser = FileHandlerPathlib(pyproject_toml_file)
+        parser = FileHandler(pyproject_toml_file)
         read = parser.read()
         assert len(read) > 1
         assert isinstance(read, str)
 
     def test_read_file_does_not_exist(
         self,
     ):
-        parser = FileHandlerPathlib("")
+        parser = FileHandler("")
         with pytest.raises(PathIsNotFileError):
             parser.read()
 
@@ -33,5 +33,5 @@ def test_raise_for_valid_file(self, mock_is_file, mock_exists, file_exists, is_f
         mock_exists.return_value = file_exists
         mock_is_file.return_value = is_file
 
-        parser = FileHandlerPathlib("fake.txt")
+        parser = FileHandler("fake.txt")
         assert parser.file_exists() is False