DoorAdmin/imaginaerraum_door_admin/webapp.py

from flask import render_template, request, flash, redirect, session, send_file, Blueprint, current_app
from werkzeug.utils import secure_filename
from flask_wtf import FlaskForm
from wtforms.fields import DateField, EmailField
from wtforms.fields import StringField, BooleanField
from wtforms.validators import DataRequired, ValidationError, EqualTo
from flask_security import auth_required, hash_password, \
    current_user, roles_required
from flask_security.views import change_password
from email_validator import validate_email

import json
import secrets
from pathlib import Path
import tempfile

from datetime import date, datetime, timedelta

def validate_valid_thru_date(form, field):
    if form.limit_validity.data:  # only check date format if limited validity of token is set
        try:
            if not field.data >= date.today():
                raise ValueError
        except ValueError as e:
            flash("Ungültiges Datum")
            raise ValidationError
    return True


class TokenForm(FlaskForm):
    name = StringField('Name', validators=[DataRequired()])
    email = EmailField('E-Mail', validators=[DataRequired()])
    organization = StringField('Organization', validators=[DataRequired()])
    limit_validity = BooleanField('Gültigkeit begrenzen?')
    valid_thru = DateField('Gültig bis', validators=[validate_valid_thru_date])
    active = BooleanField('Aktiv?')
    dsgvo = BooleanField('Einwilligung Nutzungsbedingungen erfragt?', validators=[DataRequired()])


class ConfirmDeleteForm(FlaskForm):
    name = StringField('Name', validators=[DataRequired(), EqualTo('name_confirm', 'Name stimmt nicht überein')])
    name_confirm = StringField('Name confirm')


class AdminCreationForm(FlaskForm):
    name = StringField('Name', validators=[DataRequired()])
    email = EmailField('E-Mail', validators=[DataRequired()])

door_app = Blueprint('door_app', __name__,
                        template_folder='templates')



# we override the change_password view from flask security to only allow local users to change their passwords
# LDAP users should use the LDAP self service for changing passwords
# this route needs to be defined before the Flask Security setup
@door_app.route('/change', methods=['GET', 'POST'])
@auth_required()
def change_pw():
    if current_user.has_role('local'):
        # local users can change their password
        return change_password()
    else:
        # LDAP users get redirected to the LDAP self service
        return redirect('https://ldap.imaginaerraum.de/')

# admin user management
@door_app.route('/manage_admins', methods=['GET', 'POST'])
@roles_required('super_admin')
def manage_admins():
    form = AdminCreationForm()
    if request.method == 'GET':
        users = user_datastore.user_model.query.all()
        admin_data = [{'username': u.username, 'email': u.email, 'active': u.is_active,
                       'admin': u.has_role('admin'), 'super_admin': u.has_role('super_admin'),
                       } for u in users]
        return render_template('admins.html', admin_data=admin_data, form=form)
    elif form.validate():
        if user_datastore.find_user(username=form.name.data) is not None or \
                user_datastore.find_user(email=form.email.data) is not None:
            flash("Ein Benutzer mit diesem Nutzernamen oder dieser E-Mail-Adresse existiert bereits!")
            return redirect('/manage_admins')
        else:
            pw = secrets.token_urlsafe(16)
            new_user = user_datastore.create_user(username=form.name.data, email=form.email.data,
                                                  password=hash_password(pw))
            user_datastore.add_role_to_user(new_user, 'local')
            current_app.logger.info(
                f"Super admin {current_user.username} created new user account for {new_user.username} <{new_user.email}>")
            flash(f"Ein Account für den Nutzer {new_user.username} wurde erstellt. Verwende das Passwort {pw} um den Nutzer einzuloggen.")
            db.session.commit()
            return redirect('/manage_admins')

@door_app.route('/delete_admins/<username>', methods=['GET', 'POST'])
@roles_required('super_admin')
def delete_admins(username):
    user = user_datastore.find_user(username=username)
    if user is None:
        flash(f"Ungültiger Nutzer {username}")
        return redirect('/manage_admins')
    if user.has_role('super_admin'):
        flash('Super-Admins können nicht gelöscht werden!')
        return redirect('/manage_admins')
    if user.is_active:
        flash('Aktive Nutzer können nicht gelöscht werden! Bitte den Benutzer zuerst deaktivieren.')
        return redirect('/manage_admins')

    # set up form for confirming deletion
    form = ConfirmDeleteForm()
    form.name_confirm.data = username

    if request.method == 'GET':
        # return page asking the user to confirm delete
        return render_template('delete_user.html', username=username, form=form)
    elif form.validate():
        user_datastore.delete_user(user)
        flash(f"Benutzer {username} wurde gelöscht.")
        current_app.logger.info(f"Super admin {current_user.username} deleted admin user {username}")
        db.session.commit()
        return redirect('/manage_admins')
    else:
        flash("Der eingegebene Nutzername stimmt nicht überein. Der Benutzer wurde nicht gelöscht!")
        return redirect('/manage_admins')

@door_app.route('/admin_toggle_active/<username>')
@roles_required('super_admin')
def admin_toggle_active(username):
    user = user_datastore.find_user(username=username)
    if user is None:
        flash(f"Ungültiger Nutzer {username}")
        return redirect('/manage_admins')
    if user.has_role('super_admin'):
        flash('Super-Admins können nicht deaktiviert werden!')
        return redirect('/manage_admins')
    user_datastore.toggle_active(user)
    if user.is_active:
        current_app.logger.info(f"Super admin {current_user.username} activated access for admin user {username}")
    else:
        current_app.logger.info(f"Super admin {current_user.username} deactivated access for admin user {username}")
    db.session.commit()
    return redirect('/manage_admins')

@door_app.route('/promote_admin/<username>')
@roles_required('super_admin')
def promote_admin(username):
    user = user_datastore.find_user(username=username)
    if user is None:
        flash(f"Ungültiger Nutzer {username}")
        return redirect('/manage_admins')
    if user.has_role('admin'):
        flash(f'Benutzer {username} hat bereits Admin-Rechte!')
        return redirect('/manage_admins')
    user_datastore.add_role_to_user(user, 'admin')
    current_app.logger.info(f"Super admin {current_user.username} granted admin privileges to user {username}")
    db.session.commit()
    return redirect('/manage_admins')

@door_app.route('/demote_admin/<username>')
@roles_required('super_admin')
def demote_admin(username):
    user = user_datastore.find_user(username=username)
    if user is None:
        flash(f"Ungültiger Nutzer {username}")
        return redirect('/manage_admins')
    if user.has_role('super_admin'):
        flash(f'Benutzer {username} hat Super-Admin-Rechte und kann nicht verändert werden!')
        return redirect('/manage_admins')
    if user.has_role('admin'):
        user_datastore.remove_role_from_user(user, 'admin')
        current_app.logger.info(f"Super admin {current_user.username} revoked admin privileges of user {username}")
        db.session.commit()
    else:
        flash(f'Benutzer {username} ist bereits kein Admin!')
    return redirect('/manage_admins')

@door_app.route('/backup_user_datastore')
@roles_required('super_admin')
def backup_user_datastore():
    # get list of defined admin users for backup
    users = user_datastore.user_model.query.all()
    user_data = [{'username': u.username, 'email': u.email, 'active': u.is_active, 'password_hash': u.password,
                  'roles': [r.name for r in u.roles]}
                 for u in users if not u.has_role('super_admin')]
    try:
        with tempfile.TemporaryDirectory() as tmpdir:
            file = Path(tmpdir, 'user_data.txt')
            file.write_text(json.dumps(user_data))
            return send_file(file, as_attachment=True, cache_timeout=-1)
    except Exception as e:
        return str(e)

@door_app.route('/restore_user_datastore', methods=['POST'])
@roles_required('super_admin')
def restore_user_datastore():
    # check if the post request has the file part
    if 'file' not in request.files:
        flash('Keine Datei ausgewählt!')
        return redirect(request.url)
    file = request.files['file']
    # if user does not select file, browser also
    # submit an empty part without filename
    if file.filename == '':
        flash('Keine Datei ausgewählt!')
        return redirect('/manage_admins')
    filename = secure_filename(file.filename)
    if file and filename.endswith('.txt'):
        data = file.stream.read()
        try:
            # check validity of user data
            user_data = json.loads(data)
            valid = type(user_data) == list
            valid &= all(type(d) == dict for d in user_data)
            if valid:
                for d in user_data:
                    entry_valid = set(d.keys()) == { 'active', 'email', 'password_hash', 'username', 'roles'}
                    entry_valid &= all(len(d[key]) > 0 for key in ['email', 'password_hash', 'username'])
                    entry_valid &= type(d['active']) == bool
                    entry_valid &= type(d['roles']) == list
                    validate_email(d['email'])
                    if entry_valid:
                        existing_user = user_datastore.find_user(username=d['username'], email=d['email'])
                        if existing_user is None:
                            user_datastore.create_user(username=d['username'], email=d['email'],
                                                       password=d['password_hash'], active=d['active'],
                                                       roles=d['roles'])
                            flash(f"Account für Benutzer '{d['username']} wurde wiederhergestellt.")
                        else:
                            flash(f"Benutzer '{d['username']} existiert bereits. Eintrag wird übersprungen.")
                    else:
                        raise ValueError(f"Ungültige Daten für User Entry {d}")
            else:
                raise ValueError("Admin User Datei hat ungültiges Format.")
        except Exception as e:
            flash(f"Die Datei konnte nicht gelesen werden. Exception: {e}")
            return redirect('/manage_admins')
        flash("Benutzer aus Datei gelesen.")
        db.session.commit()
    else:
        flash("Ungültige Dateiendung")
    return redirect('/manage_admins')
# main page
@door_app.route('/')
def door_lock():
    with current_app.app_context():
        return render_template('index.html', door_state=current_app.door.state, encoder_position=current_app.door.encoder_position)

# token overview
@door_app.route('/tokens')
@roles_required('admin')
def list_tokens():
    tokens = current_app.door.get_tokens()
    assigned_tokens = {t: data for t, data in tokens.items() if not data['inactive']}
    inactive_tokens = {t: data for t, data in tokens.items() if data['inactive']}
    return render_template('tokens.html', assigned_tokens=assigned_tokens, inactive_tokens=inactive_tokens)

@door_app.route('/token-log')
@roles_required('super_admin')
def token_log():
    log = []
    try:
        with open(current_app.config['NFC_LOG']) as f:
            log += f.readlines()
        log.reverse()
        log = [l.split(' - ') for l in log]
        return render_template('token_log.html', log=log)
    except Exception as e:
        flash(f"NFC logfile {Path(current_app.config['NFC_LOG']).absolute()} konnte nicht gelesen werden. Exception: {e}")
        return redirect('/')

# routes for registering, editing and deleting tokens
@door_app.route('/register-token', methods=['GET', 'POST'])
@roles_required('admin')
def register():
    """Register new token for locking and unlocking the door.

    This route displays the most recently scanned invalid token as reported in the logfile and provides a form for
    entering user info (name, email, valid thru date (optional)) for the new token.

    If the route is called via POST the provided form data is checked and if the check succeeds the /store-token route
    will be called which adds the new token to the database.
    """
    token = current_app.door.get_most_recent_token()

    recent_token = {}
    if {'token', 'timestamp'}.issubset(set(token.keys())):
        dt = datetime.utcnow() - token['timestamp']
        if  dt < timedelta(minutes=10):
            recent_token = token
            recent_token['timedelta_minutes'] = int(dt.total_seconds() / 60.0)

    form = TokenForm()
    if request.method == 'GET':
        # set default valid thru date to today to make sure form validity check passes
        # (will not be used if limited validity is disabled)
        form.valid_thru.data = date.today()

        return render_template('register.html', token=recent_token, form=form)
    elif request.method == 'POST' and form.validate():
        # store data in session cookie
        session['token'] = current_app.door.get_most_recent_token()['token']
        session['name'] = form.name.data
        session['email'] = form.email.data
        session['organization'] = form.organization.data
        if form.limit_validity.data:
            session['valid_thru'] = form.valid_thru.data.isoformat()
        else:
            session['valid_thru'] = ''
        session['inactive'] = not form.active.data
        return redirect('/store-token')
    else:
        return render_template('register.html', token=recent_token, form=form)

@door_app.route('/edit-token/<token>', methods=['GET', 'POST'])
@roles_required('admin')
def edit_token(token):
    """Edit data in the token file (name, email, valid_thru date, active/inactive).

    If the route is accessed via GET it will provide a form for editing the currently stored data for the user.
    If the route is accessed via POST it will check if the form data is good and then store the modified user data in
    the database (by redirecting to the /store-token route)

    Parameters
    ----------
    token : str
        The token for which data should be edited.
    """
    form = TokenForm(request.form)
    form.dsgvo.validators = []  # we skip the validation of the DSGVO checkbox here because we assume the user agreed
    # to it before
    if request.method == 'GET':
        tokens = current_app.door.get_tokens()
        if token in tokens:
            # set default for form according to values from the token file
            et = tokens[token]
            form.active.data = not et['inactive']
            form.name.data = et['name'] if et['name'] else ''
            form.email.data = et['email'] if et['email'] else ''
            form.organization.data = et['organization'] if et['organization'] else ''

            # for the valid thru date we use today's date in case there is not valid date in the database
            try:
                form.valid_thru.data = date.fromisoformat(et['valid_thru'])
                form.limit_validity.data = True
            except Exception:
                form.valid_thru.data = date.today()

            return render_template('edit.html', token=token, form=form)
        else:
            # flash an error message if the route is accessed with an invalid token
            flash(f'Ausgewaehlter Token {token} in Tokenfile nicht gefunden.')
            return redirect('/tokens')
    elif request.method == 'POST':
        if form.validate():
            # store data in session cookie
            session['token'] = token
            session['name'] = form.name.data
            session['organization'] = form.organization.data
            session['email'] = form.email.data
            if form.limit_validity.data:
                session['valid_thru'] = form.valid_thru.data.isoformat()
            else:
                session['valid_thru'] = ''
            session['inactive'] = not form.active.data
            return redirect(f'/store-token')
        else:
            return render_template('edit.html', token=token, form=form)

@door_app.route('/store-token')
@roles_required('admin')
def store_token():
    """Store token to the token file on disk.

    This will use the token id and the associated data stored in the session cookie (filled by register_token() or
     edit_token()) and create/modify a token and store the new token file to disk.
    """
    token = session['token']
    tokens = current_app.door.get_tokens()
    tokens[token] = {'name': session['name'],
                     'email': session['email'],
                     'valid_thru': session['valid_thru'],
                     'inactive': session['inactive'],
                     'organization': session['organization']}
    try:
        current_app.door.store_tokens(tokens)
        current_app.logger.info(f"Token {token} stored in database by admin user {current_user.username}")
    except Exception as e:
        flash(f"Error during store_tokens. Exception: {e}")
    return redirect('/tokens')

@door_app.route('/delete-token/<token>', methods=['GET', 'POST'])
@roles_required('admin')
def delete_token(token):
    """Delete the given token from the token file and store the new token file to disk

    Parameters
    ----------
    token : str
        The token to delete from the database.
    """
    tokens = current_app.door.get_tokens()

    if token in tokens:
        token_to_delete = tokens[token]

        # set up form for confirming deletion
        form = ConfirmDeleteForm()
        form.name_confirm.data = token_to_delete['name']

        if request.method == 'GET':
            # return page asking the user to confirm delete
            return render_template('delete.html', token=token_to_delete, form=form)
        elif form.validate():
            # form validation successful -> can delete the token
            tokens.pop(token)
            try:
                current_app.door.store_tokens(tokens)
                current_app.logger.info(f"Token {token} was deleted from database by admin user {current_user.username}")
            except Exception as e:
                flash(f"Error during store_tokens. Exception: {e}")
            flash(f"Token {token} wurde gelöscht!")
            return redirect('/tokens')
        else:
            # form validation failed -> return to token overview and flash message
            flash(
                f"Der eingegebene Name stimmt nicht überein. Der Token {token} von {token_to_delete['name']} wurde nicht gelöscht.")
            return redirect('/tokens')
    else:
        flash(f'Ungültiger Token {token} für Löschung.')
        return redirect('/tokens')

@door_app.route('/deactivate-token/<token>')
@roles_required('admin')
def deactivate_token(token):
    """Deactivate access for the given token. This updates the token file on disk.

    Parameters
    ----------
    token : str
        The token to deactivate.
    """
    tokens = current_app.door.get_tokens()
    if token in tokens:
        tokens[token]['inactive'] = True
        try:
            current_app.door.store_tokens(tokens)
            current_app.logger.info(f"Token {token} deactivated by admin user {current_user.username}")
        except Exception as e:
            flash(f"Error during store_tokens. Exception: {e}")
    return redirect('/tokens')

@door_app.route('/backup_tokens')
@roles_required('admin')
def backup_tokens():
    # get list of defined admin users for backup
    tokens = current_app.door.get_tokens()
    try:
        with tempfile.TemporaryDirectory() as tmpdir:
            file = Path(tmpdir, 'token_data.txt')
            file.write_text(json.dumps(tokens))
            return send_file(file, as_attachment=True, cache_timeout=-1)
    except Exception as e:
        return str(e)

@door_app.route('/open')
@auth_required()
def open_door():
    try:
        current_app.door.open_door(user=current_user.username)
        current_app.logger.info(f"Door opened by admin user {current_user.username}")
    except Exception as e:
        flash(f'Could not open door. Exception: {e}')
    return redirect('/')

# routes for opening and closing the door via the web interface
@door_app.route('/close')
@auth_required()
def close_door():
    try:
        current_app.door.close_door(user=current_user.username)
        current_app.logger.info(f"Door closed by admin user {current_user.username}")
    except Exception as e:
        flash(f'Could not close door. Exception: {e}')
    return redirect('/')