API: Integrate OpenAPI export script

Move OpenAPI export as an env var within the main function. This
allows for easy export by running main.

In addition, an env variable provides global and explicit state to
disable conditional wheel imports (ex. Exl2 and torch) which caused
errors at first.

Signed-off-by: kingbri <bdashore3@proton.me>

main.py

@@ -1,6 +1,8 @@
 """The main tabbyAPI module. Contains the FastAPI server and endpoints."""
 
 import asyncio
+import aiofiles
+import json
 import os
 import pathlib
 import signal
@@ -15,7 +17,7 @@ from common.logger import setup_logger
 from common.networking import is_port_in_use
 from common.signals import signal_handler
 from common.utils import unwrap
-from endpoints.server import start_api
+from endpoints.server import export_openapi, start_api
 
 
 async def entrypoint(args: Optional[dict] = None):
@@ -27,6 +29,15 @@ async def entrypoint(args: Optional[dict] = None):
     signal.signal(signal.SIGINT, signal_handler)
     signal.signal(signal.SIGTERM, signal_handler)
 
+    if os.getenv("EXPORT_OPENAPI"):
+        openapi_json = export_openapi()
+
+        async with aiofiles.open("openapi.json", "w") as f:
+            await f.write(json.dumps(openapi_json))
+            logger.info("Successfully wrote OpenAPI spec to openapi.json")
+
+        return
+
     # Load from YAML config
     config.from_file(pathlib.Path("config.yml"))