Allow test env and TestClient host

Add TESTING=true to the CI workflow and set APP_ENV=test in tests so test runs are marked as testing. Update TrustedHostMiddleware to treat 'test' like 'development' (allow all hosts) and include 'testserver' in allowed hosts for non-dev cases so FastAPI's TrustedHost won't block TestClient requests.

.github/workflows/ci.yml

@@ -46,6 +46,7 @@ jobs:
             --tb=short
         env:
           APP_ENV: test
+          TESTING: true
       - name: Upload coverage report
         uses: codecov/codecov-action@v4
         if: matrix.python-version == '3.11'

app.py

@@ -79,7 +79,7 @@ from uvicorn.middleware.proxy_headers import ProxyHeadersMiddleware
 # 1. Trusted Host (Prevent Host-header injection)
 app.add_middleware(
     TrustedHostMiddleware, 
-    allowed_hosts=["*"] if settings.app_env == "development" else [f"localhost", "127.0.0.1", "*.github.io"] 
+    allowed_hosts=["*"] if settings.app_env in ("development", "test") else [f"localhost", "127.0.0.1", "*.github.io", "testserver"] 
 )
 
 # 2. Proxy Headers (Support Docker/Reverse-proxy)

tests/conftest.py

@@ -1,6 +1,7 @@
 import pytest
 import os
 os.environ["TESTING"] = "true"
+os.environ["APP_ENV"] = "test"
 from fastapi.testclient import TestClient
 from sqlmodel import SQLModel, Session, create_engine
 from sqlmodel.pool import StaticPool