feat(shared): add config trailing slash sanitizer (#1870)

shared/libretime_shared/config.py

@@ -1,19 +1,23 @@
 import sys
 from os import environ
 from pathlib import Path
-from typing import Any, Dict, List, Optional, Union
+from typing import TYPE_CHECKING, Any, Dict, List, Optional, Union
 
 from loguru import logger
 
 # pylint: disable=no-name-in-module
-from pydantic import AnyHttpUrl, BaseModel, ValidationError
+from pydantic import AnyHttpUrl, BaseModel, ValidationError, validator
 from pydantic.fields import ModelField
 from pydantic.utils import deep_update
 from yaml import YAMLError, safe_load
 
+if TYPE_CHECKING:
+    from pydantic.typing import AnyClassMethod
+
 DEFAULT_ENV_PREFIX = "LIBRETIME"
 DEFAULT_CONFIG_FILEPATH = Path("/etc/libretime/config.yml")
 
+
 # pylint: disable=too-few-public-methods
 class BaseConfig(BaseModel):
     """
@@ -103,16 +107,30 @@ class BaseConfig(BaseModel):
         return {}
 
 
+def no_trailing_slash_validator(key: str) -> "AnyClassMethod":
+    # pylint: disable=unused-argument
+    def strip_trailing_slash(cls: Any, value: str) -> str:
+        return value.rstrip("/")
+
+    return validator(key, pre=True, allow_reuse=True)(strip_trailing_slash)
+
+
 # pylint: disable=too-few-public-methods
 class GeneralConfig(BaseModel):
     public_url: AnyHttpUrl
     api_key: str
 
+    # Validators
+    _public_url_no_trailing_slash = no_trailing_slash_validator("public_url")
+
 
 # pylint: disable=too-few-public-methods
 class StorageConfig(BaseModel):
     path: str = "/srv/libretime"
 
+    # Validators
+    _path_no_trailing_slash = no_trailing_slash_validator("path")
+
 
 # pylint: disable=too-few-public-methods
 class DatabaseConfig(BaseModel):

shared/tests/config_test.py

@@ -3,21 +3,31 @@ from pathlib import Path
 from typing import List
 from unittest import mock
 
-from pydantic import BaseModel
+from pydantic import AnyHttpUrl, BaseModel
 from pytest import mark, raises
 
-from libretime_shared.config import BaseConfig, DatabaseConfig, RabbitMQConfig
+from libretime_shared.config import (
+    BaseConfig,
+    DatabaseConfig,
+    RabbitMQConfig,
+    no_trailing_slash_validator,
+)
 
 
 # pylint: disable=too-few-public-methods
 class FixtureConfig(BaseConfig):
+    public_url: AnyHttpUrl
     api_key: str
     allowed_hosts: List[str] = []
     database: DatabaseConfig
     rabbitmq: RabbitMQConfig = RabbitMQConfig()
 
+    # Validators
+    _public_url_no_trailing_slash = no_trailing_slash_validator("public_url")
+
 
 FIXTURE_CONFIG_RAW = """
+public_url: http://libretime.example.com/
 api_key: "f3bf04fc"
 allowed_hosts:
   - example.com
@@ -49,6 +59,7 @@ def test_base_config(tmp_path: Path):
     ):
         config = FixtureConfig(filepath=config_filepath)
 
+        assert config.public_url == "http://libretime.example.com"
         assert config.api_key == "f3bf04fc"
         assert config.allowed_hosts == ["example.com", "sub.example.com"]
         assert config.database.host == "localhost"