Unable to run PydanticAI

Hi, I have been trying for days to deploy the python code with pydanticai. Locally, everything works well, but on vercel, I am constantly getting FUNCTION_INVOCATION_FAILED error. when I check the log, I see the following:

Traceback (most recent call last):
File "/var/task/vc__handler__python.py", line 14, in <module>
__vc_spec.loader.exec_module(__vc_module)
File "<frozen importlib._bootstrap_external>", line 995, in exec_module
File "<frozen importlib._bootstrap>", line 488, in _call_with_frames_removed
File "/var/task/src/main_vercel.py", line 1, in <module>
from fastapi import FastAPI, Request, WebSocket
File "/var/task/fastapi/__init__.py", line 7, in <module>
from .applications import FastAPI as FastAPI
File "/var/task/fastapi/applications.py", line 16, in <module>
from fastapi import routing
File "/var/task/fastapi/routing.py", line 24, in <module>
from fastapi import params
File "/var/task/fastapi/params.py", line 5, in <module>
from fastapi.openapi.models import Example
File "/var/task/fastapi/openapi/models.py", line 4, in <module>
from fastapi._compat import (
File "/var/task/fastapi/_compat.py", line 21, in <module>
from fastapi.exceptions import RequestErrorModel
File "/var/task/fastapi/exceptions.py", line 3, in <module>
from pydantic import BaseModel, create_model
File "<frozen importlib._bootstrap>", line 1412, in _handle_fromlist
File "/var/task/pydantic/__init__.py", line 421, in __getattr__
module = import_module(module_name, package=package)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/var/lang/lib/python3.12/importlib/__init__.py", line 90, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/var/task/pydantic/main.py", line 34, in <module>
from ._internal import (
File "/var/task/pydantic/_internal/_model_construction.py", line 25, in <module>
from ._generate_schema import GenerateSchema
File "/var/task/pydantic/_internal/_generate_schema.py", line 42, in <module>
from uuid import UUID
File "/var/task/uuid.py", line 138
if not 0 <= time_low < 1<<32L:
^
SyntaxError: invalid decimal literal
Python process exited with exit status: 1. The logs above can help with debugging the issue.

the main_vercel.py script is the following:

from fastapi import FastAPI, Request, WebSocket
from fastapi.middleware.cors import CORSMiddleware
from dotenv import load_dotenv
import os
from src.routers import (
    image_router, 
    auth_router, 
    financial_stats_router, 
    receipt, 
    financial_analytics_router, 
    store, 
    tags,
    spending_sheet,
    categories,
    user_settings_router
)
from src.websockets.websocket_manager import manager
from src.database.db_utils import init_db
from src.type_defs.dynamic_types import initialize_types
from contextlib import asynccontextmanager

# Load environment variables
load_dotenv()

# Define lifespan first
@asynccontextmanager
async def lifespan(app: FastAPI):
    """Lifespan context manager for FastAPI app"""
    # Startup
    await init_db()
    await initialize_types()
    yield
    # Shutdown
    # Add any cleanup code here

# Create FastAPI app instance ONCE with lifespan
app = FastAPI(
    title="Expenzor API",
    description="Backend API for Expenzor expense tracking application",
    version="1.0.0",
    lifespan=lifespan
)

# Configure CORS
origins = os.getenv("ALLOWED_ORIGINS", https://expenzor.com,https://www.expenzor.com").split(",")

app.add_middleware(
    CORSMiddleware,
    allow_origins=origins,
    allow_credentials=True,
    allow_methods=["*"],  # Allows all methods
    allow_headers=["*"],  # Allows all headers
    expose_headers=["*"]  # Exposes all headers
)

# Add request logging middleware for production
@app.middleware("http")
async def log_requests(request: Request, call_next):
    # Log basic request info
    print(f"
--- Request ---")
    print(f"Method: {request.method}")
    print(f"URL: {request.url}")
    
    # Skip body logging for multipart/form-data (file uploads)
    if not request.headers.get("content-type", "").startswith("multipart/form-data"):
        body = await request.body()
        try:
            print(f"Body: {body.decode()}")
        except UnicodeDecodeError:
            print("Body: <binary data>")
    else:
        print("Body: <file upload>")
    
    response = await call_next(request)
    print(f"Response status code: {response.status_code}")
    return response

# WebSocket endpoint
@app.websocket("/ws/{client_id}")
async def websocket_endpoint(websocket: WebSocket, client_id: str):
    print(f"WebSocket connection attempt from client: {client_id}")
    await manager.connect(websocket, client_id)
    try:
        while True:
            data = await websocket.receive_text()
            print(f"Received message from client {client_id}: {data}")
    except Exception as e:
        print(f"WebSocket error for client {client_id}: {e}")
    finally:
        print(f"WebSocket connection closed for client {client_id}")
        await manager.disconnect(websocket, client_id)

# Include routers
app.include_router(image_router)
app.include_router(auth_router)
app.include_router(financial_stats_router)
app.include_router(receipt.router)
app.include_router(financial_analytics_router)
app.include_router(store.router)
app.include_router(tags.router)
app.include_router(spending_sheet.router)
app.include_router(categories.router)
app.include_router(user_settings_router)

# Root endpoint
@app.get("/")
async def root():
    return {"message": "Welcome to Expenzor API"}

# Health check endpoint
@app.get("/health")
async def health_check():
    return {"status": "ok"}

if __name__ == "__main__":
    import uvicorn
    import sys
    
    # Determine environment
    env = os.getenv("ENV", "development")
    
    # Configure server settings based on environment
    host = "0.0.0.0"
    port = int(os.getenv("PORT", "8000"))
    reload_enabled = env == "development"
    
    # Check if running in debug mode
    is_debug = sys.gettrace() is not None
    
    if is_debug:
        print("Debug mode detected. Use the 'FastAPI' launch configuration to debug with the server running.")
    else:
        print(f"Starting server in {env} mode")
        print(f"Host: {host}")
        print(f"Port: {port}")
        print(f"Auto-reload: {'enabled' if reload_enabled else 'disabled'}")
        
        if reload_enabled:
            # When reload is enabled, we need to use the import string
            uvicorn.run(
                "src.main:app",
                host=host,
                port=port,
                reload=True,
                log_level="info"
            )
        else:
            # When reload is disabled, we can use the app instance directly
            uvicorn.run(
                app,
                host=host,
                port=port,
                reload=False,
                log_level="info"
            )

these are essential imports in some other script:

from dataclasses import dataclass
import asyncio
from pydantic import BaseModel, Field
from pydantic_ai import Agent, RunContext
from uuid import UUID, uuid4

this is the requirements.txt file:

aiohappyeyeballs==2.4.4
aiohttp==3.11.11
aiosignal==1.3.2
annotated-types==0.7.0
anyio==4.8.0
asyncpg==0.29.0
attrs==25.1.0
bcrypt==4.2.1
boto3==1.29.0
botocore==1.32.7
cachetools==5.5.1
certifi==2025.1.31
cffi==1.17.1
charset-normalizer==3.4.1
click==8.1.8
colorama==0.4.6
cryptography==44.0.0
deprecation==2.1.0
distro==1.9.0
dnspython==2.7.0
ecdsa==0.19.0
email_validator==2.2.0
eval_type_backport==0.2.2
fastapi==0.115.0
fastavro==1.10.0
filelock==3.17.0
frozenlist==1.5.0
fsspec==2025.2.0
google-auth==2.38.0
greenlet==3.1.1
griffe==1.5.6
h11==0.14.0
h2==4.2.0
hpack==4.1.0
httpcore==1.0.7
httptools==0.6.4
httpx==0.28.1
httpx-sse==0.4.0
huggingface-hub==0.28.1
hyperframe==6.1.0
idna==3.10
jiter==0.8.2
jmespath==1.0.1
jsonpath-python==1.0.6
logfire-api==3.5.0
multidict==6.1.0
mypy-extensions==1.0.0
ollama==0.4.7
openai==1.61.0
packaging==24.2
passlib==1.7.4
Pillow==10.1.0
postgrest==0.19.3
propcache==0.2.1
pyasn1==0.6.1
pyasn1_modules==0.4.1
pycparser==2.22
pydantic-ai==0.0.21
pydantic_core==2.27.2
python-dateutil==2.9.0.post0
python-dotenv==1.0.0
python-jose==3.3.0
python-magic==0.4.27
python-multipart==0.0.6
PyYAML==6.0.2
realtime==2.3.0
requests==2.32.3
rsa==4.9
s3transfer==0.7.0
six==1.17.0
sniffio==1.3.1
SQLAlchemy==2.0.23
storage3==0.11.3
StrEnum==0.4.15
supabase==2.12.0
supafunc==0.9.3
tokenizers==0.21.0
tqdm==4.67.1
types-requests==2.32.0.20241016
typing-inspect==0.9.0
typing_extensions==4.12.2
urllib3==2.0.7
uvicorn==0.30.6
uvloop==0.21.0
watchfiles==1.0.4
websockets==12.0
yarl==1.18.3

I would be thankful if anyone helped me with solving the issue. I suspect there might be an issue with pydantic v2.x but I can't use older version due to other dependencies.

""" Patched UUID module for Python 3.12 compatibility. This module provides a drop-in replacement for the standard uuid module. """ import os import random from typing import Optional, Union, Tuple # Constants from the original UUID module NAMESPACE_DNS = '6ba7b810-9dad-11d1-80b4-00c04fd430c8' NAMESPACE_URL = '6ba7b811-9dad-11d1-80b4-00c04fd430c8' NAMESPACE_OID = '6ba7b812-9dad-11d1-80b4-00c04fd430c8' NAMESPACE_X500 = '6ba7b814-9dad-11d1-80b4-00c04fd430c8' class UUID: def __init__(self, hex: Optional[str] = None, bytes_: Optional[bytes] = None, int_: Optional[int] = None, version: Optional[int] = None): if [hex, bytes_, int_].count(None) != 2: raise TypeError('Need exactly one of hex, bytes_, or int_') if hex is not None: hex = hex.replace('urn:', '').replace('uuid:', '') hex = hex.strip('{}').replace('-', '') if len(hex) != 32: raise ValueError('Invalid UUID string') self._int = int(hex, 16) elif bytes_ is not None: if len(bytes_) != 16: raise ValueError('Invalid UUID bytes') self._int = int.from_bytes(bytes_, byteorder='big') elif int_ is not None: self._int = int_ if version is not None: if not 1 <= version <= 5: raise ValueError('Invalid version number') # Set version self._int &= ~(0xf000) self._int |= version << 12 @property def bytes(self) -> bytes: return self._int.to_bytes(16, byteorder='big') @property def hex(self) -> str: return '%032x' % self._int @property def int(self) -> int: return self._int def __str__(self) -> str: hex = self.hex return f'{hex[:8]}-{hex[8:12]}-{hex[12:16]}-{hex[16:20]}-{hex[20:]}' def __repr__(self) -> str: return f'UUID({str(self)})' def __eq__(self, other: object) -> bool: if isinstance(other, UUID): return self._int == other._int return NotImplemented def __hash__(self) -> int: return hash(self._int) def uuid4() -> UUID: """Generate a random UUID (version 4).""" # Get 16 random bytes random_bytes = os.urandom(16) # Set version 4 and variant bits random_bytes = bytearray(random_bytes) random_bytes[6] = (random_bytes[6] & 0x0f) | 0x40 # version 4 random_bytes[8] = (random_bytes[8] & 0x3f) | 0x80 # variant return UUID(bytes_=bytes(random_bytes)) # Expose the main functions and constants __all__ = ['UUID', 'uuid4', 'NAMESPACE_DNS', 'NAMESPACE_URL', 'NAMESPACE_OID', 'NAMESPACE_X500']

Traceback (most recent call last): File "/var/task/vc__handler__python.py", line 14, in <module> __vc_spec.loader.exec_module(__vc_module) File "<frozen importlib._bootstrap_external>", line 995, in exec_module File "<frozen importlib._bootstrap>", line 488, in _call_with_frames_removed File "/var/task/src/main_vercel.py", line 1, in <module> from fastapi import FastAPI, Request, WebSocket File "/var/task/fastapi/__init__.py", line 7, in <module> from .applications import FastAPI as FastAPI File "/var/task/fastapi/applications.py", line 16, in <module> from fastapi import routing File "/var/task/fastapi/routing.py", line 24, in <module> from fastapi import params File "/var/task/fastapi/params.py", line 5, in <module> from fastapi.openapi.models import Example File "/var/task/fastapi/openapi/models.py", line 4, in <module> from fastapi._compat import ( File "/var/task/fastapi/_compat.py", line 21, in <module> from fastapi.exceptions import RequestErrorModel File "/var/task/fastapi/exceptions.py", line 3, in <module> from pydantic import BaseModel, create_model File "<frozen importlib._bootstrap>", line 1412, in _handle_fromlist File "/var/task/pydantic/__init__.py", line 421, in __getattr__ module = import_module(module_name, package=package) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/var/lang/lib/python3.12/importlib/__init__.py", line 90, in import_module return _bootstrap._gcd_import(name[level:], package, level) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/var/task/pydantic/main.py", line 34, in <module> from ._internal import ( File "/var/task/pydantic/_internal/_model_construction.py", line 25, in <module> from ._generate_schema import GenerateSchema File "/var/task/pydantic/_internal/_generate_schema.py", line 42, in <module> from uuid import UUID File "/var/task/uuid.py", line 138 if not 0 <= time_low < 1<<32L: ^ SyntaxError: invalid decimal literal Python process exited with exit status: 1. The logs above can help with debugging the issue.

from fastapi import FastAPI, Request, WebSocket from fastapi.middleware.cors import CORSMiddleware from dotenv import load_dotenv import os from src.routers import ( image_router, auth_router, financial_stats_router, receipt, financial_analytics_router, store, tags, spending_sheet, categories, user_settings_router ) from src.websockets.websocket_manager import manager from src.database.db_utils import init_db from src.type_defs.dynamic_types import initialize_types from contextlib import asynccontextmanager # Load environment variables load_dotenv() # Define lifespan first @asynccontextmanager async def lifespan(app: FastAPI): """Lifespan context manager for FastAPI app""" # Startup await init_db() await initialize_types() yield # Shutdown # Add any cleanup code here # Create FastAPI app instance ONCE with lifespan app = FastAPI( title="Expenzor API", description="Backend API for Expenzor expense tracking application", version="1.0.0", lifespan=lifespan ) # Configure CORS origins = os.getenv("ALLOWED_ORIGINS", https://expenzor.com,https://www.expenzor.com").split(",") app.add_middleware( CORSMiddleware, allow_origins=origins, allow_credentials=True, allow_methods=["*"], # Allows all methods allow_headers=["*"], # Allows all headers expose_headers=["*"] # Exposes all headers ) # Add request logging middleware for production @app.middleware("http") async def log_requests(request: Request, call_next): # Log basic request info print(f" --- Request ---") print(f"Method: {request.method}") print(f"URL: {request.url}") # Skip body logging for multipart/form-data (file uploads) if not request.headers.get("content-type", "").startswith("multipart/form-data"): body = await request.body() try: print(f"Body: {body.decode()}") except UnicodeDecodeError: print("Body: <binary data>") else: print("Body: <file upload>") response = await call_next(request) print(f"Response status code: {response.status_code}") return response # WebSocket endpoint @app.websocket("/ws/{client_id}") async def websocket_endpoint(websocket: WebSocket, client_id: str): print(f"WebSocket connection attempt from client: {client_id}") await manager.connect(websocket, client_id) try: while True: data = await websocket.receive_text() print(f"Received message from client {client_id}: {data}") except Exception as e: print(f"WebSocket error for client {client_id}: {e}") finally: print(f"WebSocket connection closed for client {client_id}") await manager.disconnect(websocket, client_id) # Include routers app.include_router(image_router) app.include_router(auth_router) app.include_router(financial_stats_router) app.include_router(receipt.router) app.include_router(financial_analytics_router) app.include_router(store.router) app.include_router(tags.router) app.include_router(spending_sheet.router) app.include_router(categories.router) app.include_router(user_settings_router) # Root endpoint @app.get("/") async def root(): return {"message": "Welcome to Expenzor API"} # Health check endpoint @app.get("/health") async def health_check(): return {"status": "ok"} if __name__ == "__main__": import uvicorn import sys # Determine environment env = os.getenv("ENV", "development") # Configure server settings based on environment host = "0.0.0.0" port = int(os.getenv("PORT", "8000")) reload_enabled = env == "development" # Check if running in debug mode is_debug = sys.gettrace() is not None if is_debug: print("Debug mode detected. Use the 'FastAPI' launch configuration to debug with the server running.") else: print(f"Starting server in {env} mode") print(f"Host: {host}") print(f"Port: {port}") print(f"Auto-reload: {'enabled' if reload_enabled else 'disabled'}") if reload_enabled: # When reload is enabled, we need to use the import string uvicorn.run( "src.main:app", host=host, port=port, reload=True, log_level="info" ) else: # When reload is disabled, we can use the app instance directly uvicorn.run( app, host=host, port=port, reload=False, log_level="info" )

aiohappyeyeballs==2.4.4 aiohttp==3.11.11 aiosignal==1.3.2 annotated-types==0.7.0 anyio==4.8.0 asyncpg==0.29.0 attrs==25.1.0 bcrypt==4.2.1 boto3==1.29.0 botocore==1.32.7 cachetools==5.5.1 certifi==2025.1.31 cffi==1.17.1 charset-normalizer==3.4.1 click==8.1.8 colorama==0.4.6 cryptography==44.0.0 deprecation==2.1.0 distro==1.9.0 dnspython==2.7.0 ecdsa==0.19.0 email_validator==2.2.0 eval_type_backport==0.2.2 fastapi==0.115.0 fastavro==1.10.0 filelock==3.17.0 frozenlist==1.5.0 fsspec==2025.2.0 google-auth==2.38.0 greenlet==3.1.1 griffe==1.5.6 h11==0.14.0 h2==4.2.0 hpack==4.1.0 httpcore==1.0.7 httptools==0.6.4 httpx==0.28.1 httpx-sse==0.4.0 huggingface-hub==0.28.1 hyperframe==6.1.0 idna==3.10 jiter==0.8.2 jmespath==1.0.1 jsonpath-python==1.0.6 logfire-api==3.5.0 multidict==6.1.0 mypy-extensions==1.0.0 ollama==0.4.7 openai==1.61.0 packaging==24.2 passlib==1.7.4 Pillow==10.1.0 postgrest==0.19.3 propcache==0.2.1 pyasn1==0.6.1 pyasn1_modules==0.4.1 pycparser==2.22 pydantic-ai==0.0.21 pydantic_core==2.27.2 python-dateutil==2.9.0.post0 python-dotenv==1.0.0 python-jose==3.3.0 python-magic==0.4.27 python-multipart==0.0.6 PyYAML==6.0.2 realtime==2.3.0 requests==2.32.3 rsa==4.9 s3transfer==0.7.0 six==1.17.0 sniffio==1.3.1 SQLAlchemy==2.0.23 storage3==0.11.3 StrEnum==0.4.15 supabase==2.12.0 supafunc==0.9.3 tokenizers==0.21.0 tqdm==4.67.1 types-requests==2.32.0.20241016 typing-inspect==0.9.0 typing_extensions==4.12.2 urllib3==2.0.7 uvicorn==0.30.6 uvloop==0.21.0 watchfiles==1.0.4 websockets==12.0 yarl==1.18.3