feat: introduce pydantic-settings for config definition and validation (#5202)

Co-authored-by: -LAN- <laipz8200@outlook.com>

api/tests/unit_tests/settings/test_dify_settings.py

@@ -0,0 +1,62 @@
+from textwrap import dedent
+
+import pytest
+from flask import Flask
+
+from configs.app_configs import DifyConfigs
+
+EXAMPLE_ENV_FILENAME = '.env'
+
+
+@pytest.fixture
+def example_env_file(tmp_path, monkeypatch) -> str:
+    monkeypatch.chdir(tmp_path)
+    file_path = tmp_path.joinpath(EXAMPLE_ENV_FILENAME)
+    file_path.write_text(dedent(
+        """
+        CONSOLE_API_URL=https://example.com
+        """))
+    return str(file_path)
+
+
+def test_dify_configs_undefined_entry(example_env_file):
+    # load dotenv file with pydantic-settings
+    settings = DifyConfigs(_env_file=example_env_file)
+
+    # entries not defined in app settings
+    with pytest.raises(TypeError):
+        # TypeError: 'AppSettings' object is not subscriptable
+        assert settings['LOG_LEVEL'] == 'INFO'
+
+
+def test_dify_configs(example_env_file):
+    # load dotenv file with pydantic-settings
+    settings = DifyConfigs(_env_file=example_env_file)
+
+    # constant values
+    assert settings.COMMIT_SHA == ''
+
+    # default values
+    assert settings.EDITION == 'SELF_HOSTED'
+    assert settings.API_COMPRESSION_ENABLED is False
+    assert settings.SENTRY_TRACES_SAMPLE_RATE == 1.0
+
+
+def test_flask_configs(example_env_file):
+    flask_app = Flask('app')
+    flask_app.config.from_mapping(DifyConfigs(_env_file=example_env_file).model_dump())
+    config = flask_app.config
+
+    # configs read from dotenv directly
+    assert config['LOG_LEVEL'] == 'INFO'
+
+    # configs read from pydantic-settings
+    assert config['COMMIT_SHA'] == ''
+    assert config['EDITION'] == 'SELF_HOSTED'
+    assert config['API_COMPRESSION_ENABLED'] is False
+    assert config['SENTRY_TRACES_SAMPLE_RATE'] == 1.0
+
+    # value from env file
+    assert config['CONSOLE_API_URL'] == 'https://example.com'
+    # fallback to alias choices value as CONSOLE_API_URL
+    assert config['FILES_URL'] == 'https://example.com'