main.py

import models
from database import SessionLocal,engine
from models import Stock

from sqlalchemy.orm import Session
from fastapi import FastAPI, Request, Depends, BackgroundTasks
from fastapi.templating import Jinja2Templates
from pydantic import BaseModel
import yfinance

app = FastAPI()

models.Base.metadata.create_all(bind=engine)

templates = Jinja2Templates(directory="templates")

class StockRequest(BaseModel):
    symbol: str


def get_db():
    try:
        db = SessionLocal()
        yield db
    finally:
        db.close()


@app.get('/')
#pydantic: Pre-verification of data.
#get request for the base route returns this jason
def dashboard(request:Request,forward_pe=None,dividend_yield=None,ma50=False,ma200=False,db:Session = Depends(get_db)):
    """
    Exibe a pagina inicial do stock screener
    """
    stocks = db.query(Stock)

    if(forward_pe):
        stocks = stocks.filter(Stock.forward_pe < forward_pe)

    if(dividend_yield):
        stocks = stocks.filter(Stock.dividend_yield > dividend_yield)
    if(ma50):
        stocks = stocks.filter(Stock.price > Stock.ma50)
    if(ma200):
        stocks = stocks.filter(Stock.price > Stock.ma200)



    return templates.TemplateResponse("dashboard.html",{
        "request":request,
        'stocks':stocks,
        'dividend_yield':dividend_yield,
        'forward_pe':forward_pe,
        'ma200':ma200,
        'ma50':ma50
    })


def fetch_stock_data(id:int):
    db = SessionLocal()
    stock = db.query(Stock).filter(Stock.id == id).first()

    yahoo_data = yfinance.Ticker(stock.symbol)

    stock.ma200 = yahoo_data.info['twoHundredDayAverage']
    stock.ma50 = yahoo_data.info['fiftyDayAverage']
    stock.price = yahoo_data.info['previousClose']
    stock.forward_pe = yahoo_data.info['forwardPE']
    stock.forward_eps = yahoo_data.info['forwardEps']
    if(yahoo_data.info['dividendYield'] is not None):
        stock.dividend_yield = yahoo_data.info['dividendYield']*100

    db.add(stock)
    db.commit()

@app.post('/stock')
#a variavel db depende da funcao get_db.
async def create_stock(stock_request:StockRequest,background_tasks: BackgroundTasks,
    db:Session = Depends(get_db)):

    """
    Cria uma stock e guarda na base de dados
    """

    stock = Stock()
    stock.symbol = stock_request.symbol

    db.add(stock)
    db.commit()

    background_tasks.add_task(fetch_stock_data,stock.id)

    return {
        "code":"sucess",
        "message":"stock created"
    }