Drop Python 3.8 support and modernize type annotations

- Updated minimum Python version to 3.9 in pyproject.toml
- Removed Python 3.8 from CI matrix and tox environments
- Modernized type annotations to use built-in types (list, dict, set) instead of typing.List, Dict, Set
- Updated tool configurations (ruff, black, mypy) to target Python 3.9
- This eliminates compatibility issues and simplifies our CI pipeline

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: ritwik-g

.github/workflows/ci.yml

@@ -13,15 +13,11 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
-        python-version: ["3.8", "3.9", "3.10", "3.11", "3.12"]
+        python-version: ["3.9", "3.10", "3.11", "3.12"]
         exclude:
           # Skip some combinations to reduce CI time
-          - os: macos-latest
-            python-version: "3.8"
           - os: macos-latest
             python-version: "3.9"
-          - os: windows-latest
-            python-version: "3.8"
           - os: windows-latest
             python-version: "3.9"
 

coverage.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" ?>
-<coverage version="7.9.1" timestamp="1749999842814" lines-valid="910" lines-covered="735" line-rate="0.8077" branches-covered="0" branches-valid="0" branch-rate="0" complexity="0">
+<coverage version="7.9.1" timestamp="1750000013912" lines-valid="910" lines-covered="735" line-rate="0.8077" branches-covered="0" branches-valid="0" branch-rate="0" complexity="0">
 	<!-- Generated by coverage.py: https://coverage.readthedocs.io/en/7.9.1 -->
 	<!-- Based on https://raw.githubusercontent.com/cobertura/web/master/htdocs/xml/coverage-04.dtd -->
 	<sources>

helm_values_manager/errors.py

@@ -1,6 +1,6 @@
 """Centralized error handling utilities for consistent error formatting."""
 
-from typing import List, Optional
+from typing import Optional
 
 import typer
 from rich.console import Console
@@ -31,7 +31,7 @@ def print_warning(message: str) -> None:
         error_console.print(f"[yellow]Warning:[/yellow] {message}")
 
     @staticmethod
-    def print_errors(errors: List[str], context: Optional[str] = None) -> None:
+    def print_errors(errors: list[str], context: Optional[str] = None) -> None:
         """Print multiple errors at once."""
         if not errors:
             return

helm_values_manager/generator.py

@@ -1,7 +1,7 @@
 """Generator module for creating values.yaml from schema and values."""
 
 import os
-from typing import Any, Dict
+from typing import Any
 
 import yaml
 
@@ -10,7 +10,7 @@
 from helm_values_manager.utils import is_secret_reference
 
 
-def resolve_secret(secret: Dict[str, Any], key: str) -> str:
+def resolve_secret(secret: dict[str, Any], key: str) -> str:
     """Resolve a secret reference to its actual value.
 
     Args:
@@ -37,7 +37,7 @@ def resolve_secret(secret: Dict[str, Any], key: str) -> str:
     return value
 
 
-def build_nested_dict(flat_values: Dict[str, Any], schema: Schema) -> Dict[str, Any]:
+def build_nested_dict(flat_values: dict[str, Any], schema: Schema) -> dict[str, Any]:
     """Build a nested dictionary from flat values using schema paths.
 
     Args:
@@ -80,7 +80,7 @@ def build_nested_dict(flat_values: Dict[str, Any], schema: Schema) -> Dict[str,
     return result
 
 
-def generate_values(schema: Schema, values: Dict[str, Any], env: str) -> str:
+def generate_values(schema: Schema, values: dict[str, Any], env: str) -> str:
     """Generate values.yaml content from schema and environment values.
 
     Args:

helm_values_manager/models.py

@@ -1,4 +1,4 @@
-from typing import Any, Dict, List, Literal, Optional, Union
+from typing import Any, Literal, Optional, Union
 
 from pydantic import BaseModel, Field, RootModel
 
@@ -18,7 +18,7 @@ class SchemaValue(BaseModel):
 
 class Schema(BaseModel):
     version: str = Field(default="1.0", description="Schema version")
-    values: List[SchemaValue] = Field(default_factory=list, description="List of value definitions")
+    values: list[SchemaValue] = Field(default_factory=list, description="List of value definitions")
 
 
 class SecretReference(BaseModel):
@@ -27,10 +27,10 @@ class SecretReference(BaseModel):
 
 
 # Type for a value in the values file - can be a regular value or a secret reference
-ValueEntry = Union[str, int, float, bool, List, Dict, SecretReference]
+ValueEntry = Union[str, int, float, bool, list, dict, SecretReference]
 
 
-class ValuesFile(RootModel[Dict[str, Any]]):
+class ValuesFile(RootModel[dict[str, Any]]):
     """Represents a values file for an environment."""
 
-    root: Dict[str, Any] = Field(default_factory=dict)
+    root: dict[str, Any] = Field(default_factory=dict)

helm_values_manager/utils.py

@@ -1,6 +1,6 @@
 import json
 from pathlib import Path
-from typing import Any, Dict, Optional
+from typing import Any, Optional
 
 from helm_values_manager.models import Schema
 
@@ -51,7 +51,7 @@ def get_values_file_path(env: str, values_path: Optional[str] = None) -> str:
     return f"values-{env}.json"
 
 
-def load_values(env: str, values_path: Optional[str] = None) -> Dict[str, Any]:
+def load_values(env: str, values_path: Optional[str] = None) -> dict[str, Any]:
     """Load values for an environment."""
     path = Path(get_values_file_path(env, values_path))
     if not path.exists():
@@ -63,7 +63,7 @@ def load_values(env: str, values_path: Optional[str] = None) -> Dict[str, Any]:
     return data
 
 
-def save_values(values: Dict[str, Any], env: str, values_path: Optional[str] = None) -> None:
+def save_values(values: dict[str, Any], env: str, values_path: Optional[str] = None) -> None:
     """Save values for an environment."""
     path = get_values_file_path(env, values_path)
     with open(path, "w") as f:

helm_values_manager/validator.py

@@ -3,7 +3,7 @@
 import json
 import os
 from pathlib import Path
-from typing import Dict, List, Any, Optional, Set
+from typing import Any, Optional
 
 from rich.console import Console
 from rich.text import Text
@@ -47,7 +47,7 @@ class Validator:
     def __init__(self, schema_path: Path, values_base_path: Optional[Path] = None):
         self.schema_path = schema_path
         self.values_base_path = values_base_path or Path(".")
-        self.errors: List[ValidationError] = []
+        self.errors: list[ValidationError] = []
 
     def validate_all(self, env: Optional[str] = None) -> bool:
         """Validate schema and optionally values for specific environment."""
@@ -88,8 +88,8 @@ def _validate_schema(self):
             self.errors.append(ValidationError("Schema", f"Unsupported version: {schema.version}"))
 
         # Validate each entry
-        seen_keys: Set[str] = set()
-        seen_paths: Set[str] = set()
+        seen_keys: set[str] = set()
+        seen_paths: set[str] = set()
 
         for entry in schema.values:
             # Check for duplicate keys
@@ -248,7 +248,7 @@ def print_errors(self):
             console.print(f"  - {str(error)}")
 
 
-def validate_single_environment(schema: Schema, values: Dict[str, Any], env: str) -> List[str]:
+def validate_single_environment(schema: Schema, values: dict[str, Any], env: str) -> list[str]:
     """Validate schema and values for a single environment and return list of errors.
 
     Args:
@@ -303,7 +303,7 @@ def validate_single_environment(schema: Schema, values: Dict[str, Any], env: str
     return errors
 
 
-def _validate_schema_integrity(schema: Schema) -> List[str]:
+def _validate_schema_integrity(schema: Schema) -> list[str]:
     """Validate schema for duplicate keys and paths."""
     errors = []
 

pyproject.toml

@@ -3,7 +3,7 @@ name = "helm-values-manager"
 version = "1.0.0"
 description = "A schema-driven tool for managing Helm values with environment-specific configurations and secret management"
 readme = "README.md"
-requires-python = ">=3.8"
+requires-python = ">=3.9"
 dependencies = [
     "typer>=0.16.0",
     "rich>=14.0.0",
@@ -31,14 +31,14 @@ dev-dependencies = [
 
 [tool.ruff]
 line-length = 100
-target-version = "py38"
+target-version = "py39"
 
 [tool.black]
 line-length = 100
-target-version = ["py38"]
+target-version = ["py39"]
 
 [tool.mypy]
-python_version = "3.8"
+python_version = "3.9"
 strict = true
 
 [tool.pytest.ini_options]

tox.ini

@@ -1,5 +1,5 @@
 [tox]
-envlist = py38,py39,py310,py311,py312,lint,type-check
+envlist = py39,py310,py311,py312,lint,type-check
 isolated_build = true
 
 [testenv]
@@ -20,9 +20,6 @@ setenv =
     TERM = dumb
 
 # Python version specific environments
-[testenv:py3.8]
-basepython = python3.8
-
 [testenv:py3.9]
 basepython = python3.9