Im learning about Flask and Angular and i tried to make a web app, i want to implement a register watching some examples an other things, so im doing one but i want it to do like a filter, the typical filter of the email, a filter that validates that you have a domain and not only pipo123, or validates that there are not numbers in the names.

This is my code:

@app.route('/user/register', methods=['POST'])
def register():
    r_first_name=request.get_json()['first_name']
    r_last_name=request.get_json()['last_name']
    r_email=request.get_json()['email']
    r_password=bcrypt.generate_password_hash(request.get_json()['password']).decode('utf-8')
    result=""
    if user_database_service.if_user_exists(r_email):
        result="user already exists"
        return jsonify({'result': result})
    new_user=LocalUser(first_name=r_first_name, last_name=r_last_name, email=r_email, password=r_password, created=datetime.utcnow())
    added=user_database_service.add_user(new_user)
    if added is True:
        result="user successfully added"
    else:
        result="unable to add"
    return jsonify({'result': result})

and this is the user_database_service

from sqlalchemy import create_engine, false
from sqlalchemy import exc

from sqlalchemy.orm import sessionmaker
from user_database_setup import Base, LocalUser

engine=create_engine('sqlite:///users.db')
Base.metadata.bind=engine
DBSession=sessionmaker(bind=engine)

def get_user(r_email):
    session=DBSession()
    q=session.query(LocalUser).filter(r_email == LocalUser.email).first()
    session.close()
    if q:
        resulted_user=LocalUser(id=q.id, first_name=q.first_name, last_name=q.last_name, email=q.email, password=q.password, created=q.created)
        return resulted_user
    else:
        return None

def if_user_exists(r_email):
    session=DBSession()
    q=session.query(LocalUser).filter(r_email == LocalUser.email).first()
    session.close()
    if q is None:
        return False
    else:
        return True


def add_user(new_user):
    try:
        session=DBSession()
        session.add(new_user)
        session.flush()
        session.commit()
        session.close()
        return True
    except exc.SQLAlchemyError as e:
        return False

def get_user(r_email):
    session=DBSession()
    q=session.query(LocalUser).filter(r_email == LocalUser.email).first()
    session.close()

    if q:
        result=LocalUser(id=q.id, first_name=q.first_name, last_name=q.last_name, email=q.email, password=q.password, created=q.created)
        return result
    else:
        return None

I apreciate all your tips! Thanks!

CodePudding user response：

You can check if an email adress is valid using regular expressions regex. A regex is a string that specifies some rules that you want to check.

A quick intro to regex

• [a-z] is for checking for a character between a and z
• [0-9] is for checking for digits from 0 to 9 then you can check for strings that have a letter followed by a hashtag then by a number with this regex: [a-z]#[0-9]. Some strings that satisfy this regex are a#4, s#1.

This way you can make a regex for emails, and checking if a username does not start with a number

Python library re is quite easy to use for these purposes

Here are some useful sites

https://www.w3schools.com/jsref/jsref_obj_regexp.asp

https://www.w3schools.com/python/python_regex.asp

Hope that helps!