PythonFastServer/main.py

from fastapi import FastAPI, Form, File, Request
from fastapi.responses import HTMLResponse, RedirectResponse, JSONResponse
from jinja2 import Template
import os
from typing import Annotated
from pydantic import BaseModel
import tempfile
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
import ipaddress
import psycopg2
from dateutil.parser import parse
from datetime import datetime
from fastapi.exceptions import RequestValidationError
from starlette.exceptions import HTTPException as StarletteHTTPException
from fastapi.exceptions import RequestValidationError
from fastapi.responses import PlainTextResponse, JSONResponse
from fastapi.exception_handlers import (
    http_exception_handler,
    request_validation_exception_handler,
)
import threading
import socket
import struct
from zoneinfo import ZoneInfo

temp_dir = r"/home/td/WebTemp"
tempfile.tempdir = temp_dir

app = FastAPI(title="user manager", description="User session management.", version="0.0.0.1",
               docs_url="/server/docs", redoc_url="/server/redoc", openapi_url="/server/openapi.json")

app.mount("/server/static", StaticFiles(directory="static"), name="static")
templates = Jinja2Templates(directory="templates")
distance_value = 0.0
last_updated = None
distance_value_rev = 0.0

def get_udp_water_value():
    sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
    sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
    count = 0
    while True:
        try:
            sock.bind(('', 8176))
            sock.settimeout(5.0)
            break
        except Exception as e:
            count+=1
            print("Exception: e", e)
            time.sleep(5)
            if count >= 100:
                raise e
    zone = ZoneInfo("Asia/Kolkata");
    print("Bound to address: 8176")
    global distance_value
    global last_updated
    global distance_value_rev
    while True:
        try:
            data, addr = sock.recvfrom(4)
            print(f"Got data: {data.hex()}")
            distance_value = struct.unpack('>f', data)
            distance_value_rev = struct.unpack('<f', data)
            print(f"Updated distance_value to: {distance_value}")
            last_updated = datetime.now(zone).strftime("%d/%m/%y %H:%M:%S");
        except Exception as e:
            print("Did not get any data in 5 seconds: ", e)

thread = threading.Thread(target=get_udp_water_value)
thread.start();


@app.get("/server/waterlevel", response_class=JSONResponse)
async def get_water_level(request: Request):
    global distance_value
    global last_updated
    global distance_value_rev
    return {"water_level": distance_value, "water_level_rev": distance_value_rev, "updated_on": last_updated}


# @app.post("/api/users/create", response_class=RedirectResponse)
# async def root(username: Annotated[str, Form()], password: Annotated[str, Form()],
#                new_user: Annotated[str, Form()], new_password: Annotated[str, Form()]):
#      global internal_status
#      val = helper.validate_credentials(username, password)
#      print("Validation result: ", val)
#      if val == "valid":
#         print("Valid creds")
#         helper.status_type = 'success'
#         helper.internal_status = "Created New User"
#         helper.create_new_user(new_user, new_password)
#         return RedirectResponse(url=f"/api/users/", status_code=303)
#      elif val == "invalid":
#          print("Invalid creds")
#          helper.status_type = 'danger'
#          helper.internal_status = "Invalid Credentials"
#          return RedirectResponse(url=f"/api/users/", status_code=303)
#      else:
#         print("Validation issue: ", val)
#         helper.status_type = 'danger'
#         helper.internal_status = val
#         return RedirectResponse(url="/api/users/", status_code=303)
     
# @app.post("/api/users/login")
# async def root(user: User, request: Request):
#     ip = request.headers['X-Real-IP']
#     if ipaddress.ip_address(ip) not in ipaddress.ip_network('192.168.0.0/16'):
#         return {"message": "unknown user"}
#     val = helper.validate_credentials(user.username, user.password)
#     if val == 'valid':
#         print("Valid creds generating session key")
#         (session_key, expiry_date) = helper.create_new_session_key(user.username)
#         return {"message": "credentials validated", "session_key": session_key, "expiry_date": expiry_date}
#     elif val == 'invalid':
#         print("Invalid creds.")
#         return {"message": "invalid credentials"}
#     elif val == 'session_active':
#         print("session is active.")
#         return {"message": "active session"}
    

# @app.post("/api/users/logout")
# async def root(user: User, request: Request):
#     ip = request.headers['X-Real-IP']
#     if ipaddress.ip_address(ip) not in ipaddress.ip_network('192.168.0.0/16'):
#         return {"message": "unknown user"}
#     val = helper.validate_credentials(user.username, user.password)
#     if val == 'valid':
#         print(f"User {user.username} is not active.")
#         return {"message", "user not active"}
#     elif val == 'session_active':
#         print(f"Logging out user: {user.username}, bye!")
#         ret = helper.logout_user(user.username)
#         return {"message": f"logout status: {str(ret)}"}
#     else:
#         print(f"invalid credentials.")
#         return {"message": "invalid credentials"}





# @app.exception_handler(RequestValidationError)
# async def validation_exception_handler(request, exc):
#     print(exc)
#     return PlainTextResponse(str(exc), status_code=400)


# @app.exception_handler(StarletteHTTPException)
# async def custom_http_exception_handler(request, exc):
#     print(f"OMG! An HTTP error!: {repr(exc)}")
#     return await http_exception_handler(request, exc)


# @app.exception_handler(RequestValidationError)
# async def validation_exception_handler(request, exc):
#     print(f"OMG! The client sent invalid data!: {exc}")
#     return await request_validation_exception_handler(request, exc)