csv-library-website/library/application/user/forgotpassword.py

from datetime import datetime
from uuid import uuid1

from app import db
from flask import render_template
from flask_mail import Message
from application.forms.forgotpasswordform import ForgotPasswordForm
from sqlalchemy.exc import (
    DatabaseError,
    DataError,
    InterfaceError,
    InvalidRequestError,
)
from application.models.usermodel import User


def ForgotPassword():
    forgotpasswordform = ForgotPasswordForm()
    if forgotpasswordform.validate_on_submit():
        user = User.query.filter_by(
            email=forgotpasswordform.email.data
        ).first()
        if user is not None:
            resethash = AddResetPasswordHash(user, forgotpasswordform)
            ResetPassWordMessage(user, resethash, mail)
        forgotpasswordform.email.errors.append(
            f"""If {forgotpasswordform.email.data} exists, an email is send with
            a password reset link. (If your inbox doesn't
            contain any new mail, please check your spam folder.)"""
        )
    return render_template(
        "user/forgotpassword.html", forgotpasswordform=forgotpasswordform
    )


def AddResetPasswordHash(user, forgotpasswordform):
    resethash = uuid1().hex
    try:
        user.resettime = datetime.now()
        user.resethash = resethash
        db.session.commit()
    except (InvalidRequestError, DataError, InterfaceError, DatabaseError):
        forgotpasswordform.email.errors.append("Something went wrong!")
        db.session.rollback()
    return resethash


def ResetPassWordMessage(user, resethash, mail):
    msg = Message(
        "Forgotten Password ",
        sender=("mailer", "test@this.com"),
        recipients=[user.email],
    )
    msg.html = f"""{user.username} has requested a password reset for
libary website.<br><hr>
<a href='http://localhost:5000/resetpassword/{resethash}'>Click here to
reset your password.</a>"""
    mail.send(msg)