Chapter 5

app/forms.py

@@ -1,6 +1,7 @@
 from flask_wtf import FlaskForm
 from wtforms import StringField, PasswordField, BooleanField, SubmitField
-from wtforms.validators import DataRequired
+from wtforms.validators import DataRequired, EqualTo, Email, ValidationError
+from app.models import User
 
 
 class LoginForm(FlaskForm):
@@ -8,3 +9,23 @@ class LoginForm(FlaskForm):
     password = PasswordField("Password", validators=[DataRequired()])
     remember_me = BooleanField("Remember Me")
     submit = SubmitField("Sign In")
+
+
+class RegistrationForm(FlaskForm):
+    username = StringField("Username", validators=[DataRequired()])
+    email = StringField("Email", validators=[DataRequired(), Email()])
+    password = PasswordField("Password", validators=[DataRequired()])
+    password2 = PasswordField(
+        "Repeat Password", validators=[DataRequired(), EqualTo("password")]
+    )
+    submit = SubmitField("Register")
+
+    def validate_username(self, username):
+        user = User.query.filter_by(username=username.data).first()
+        if user is not None:
+            raise ValidationError("Please use a different username.")
+
+    def validate_email(self, email):
+        user = User.query.filter_by(email=email.data).first()
+        if user is not None:
+            raise ValidationError("Please use a different email address.")