model.py

import os
from dotenv import load_dotenv

from datetime import datetime, UTC

from sqlalchemy import create_engine, Column, Integer,  String, DateTime, ForeignKey
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker, relationship

load_dotenv() # load env
DATA_DIR = os.getenv("DATA_DIR")
DB_URL = f"sqlite:////{DATA_DIR.strip('/')}/pdf_server.db"

Base = declarative_base()

class pdfs(Base):
    __tablename__ = "pdfs"
    id = Column(Integer, primary_key=True, index = True)
    path = Column(String, unique = True, nullable = False)
    created_at = Column(DateTime, default = datetime.now(UTC))

    # to access logs
    logs = relationship("changeLogs", back_populates="pdf", cascade="all, delete-orphan")

class changeLogs(Base):
    __tablename__ = "change_logs"
    id = Column(Integer, primary_key=True, index = True)
    pdf_id = Column(Integer, ForeignKey("pdfs.id"), nullable= False)
    temp_path = Column(String)
    timestamp = Column(DateTime, default = datetime.now(UTC))

    pdf = relationship("pdfs", back_populates="logs")


##### Engine and Table Creation #####
engine = create_engine(DB_URL, connect_args={"check_same_thread": False})
SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)

def init_db():
    # This command checks if tables exist; if not, it creates them.
    Base.metadata.create_all(bind=engine)

if __name__ == "__main__":
    init_db()
    print("Database initialized and tables created.")