Fixen

Author: mattgodbolt

app/config.py

@@ -1,3 +1,5 @@
+from functools import lru_cache
+
 from pydantic_settings import BaseSettings, SettingsConfigDict
 
 
@@ -10,4 +12,11 @@ class Settings(BaseSettings):
     model_config = SettingsConfigDict(env_file=".env")
 
 
-settings = Settings()
+@lru_cache
+def get_settings():
+    """Return the application settings.
+
+    A function so the actual construction is deferred until needed (avoiding test issues), and
+    lru_cached for efficiency.
+    """
+    return Settings()

app/main.py

@@ -6,7 +6,7 @@
 from fastapi.middleware.cors import CORSMiddleware
 from mangum import Mangum
 
-from app.config import settings
+from app.config import get_settings
 from app.explain import process_request
 from app.explain_api import (
     AvailableOptions,
@@ -21,7 +21,7 @@
 logger = logging.getLogger()
 logger.setLevel(logging.INFO)
 
-app = FastAPI(root_path=settings.root_path)
+app = FastAPI(root_path=get_settings().root_path)
 
 # Configure CORS - allows all origins for public API
 app.add_middleware(
@@ -34,7 +34,7 @@
 )
 handler = Mangum(app)
 
-anthropic_client = Anthropic(api_key=settings.anthropic_api_key)
+anthropic_client = Anthropic(api_key=get_settings().anthropic_api_key)
 logger.info(f"Anthropic SDK version: {anthropic_version}")
 
 

app/metrics.py

@@ -5,7 +5,7 @@
 from aws_embedded_metrics.logger.metrics_logger import MetricsLogger
 from aws_embedded_metrics.logger.metrics_logger_factory import create_metrics_logger
 
-from app.config import settings
+from app.config import get_settings
 
 
 class MetricsProvider(ABC):
@@ -52,7 +52,7 @@ async def get_metrics_provider() -> AsyncGenerator[MetricsProvider]:
     When metrics are enabled, creates a CloudWatch metrics provider and ensures
     proper flushing. When disabled, provides a no-op implementation.
     """
-    if settings.metrics_enabled:
+    if get_settings().metrics_enabled:
         metrics_logger = create_metrics_logger()
         metrics_logger.set_namespace("CompilerExplorer")
         provider = CloudWatchMetricsProvider(metrics_logger)