I have 2 forms on my page - login form and registration form. Now I want to use AJAX to validate those forms so I can see input errors without refreshing the page. I tried to add all that AJAX things to the forms I already had but now it seems like the form validation doesn't work.
routes.py
@users.route('/login', methods=['GET', 'POST'])
def login():
loginForm = LoginForm()
registerForm = RegisterForm()
if request.method == 'POST':
if registerForm.validate():
return'wow it works'
return 'something is wrong'
return render_template("login.html", loginForm=loginForm, registerForm=registerForm)
P.S. also I'd like to know how to check which form to valide when sending a POST request? Right now I'm just trying to figure out how to fix the problem so I only use registration form. But when I have both how to valide one form and ignore another one?
login.html
const signUpButton = document.getElementById("signUp");
const signInButton = document.getElementById("signIn");
const container = document.getElementById("container");
signUpButton.addEventListener('click', () => {
container.classList.add("right-panel-active");
});
signInButton.addEventListener('click', () => {
container.classList.remove("right-panel-active");
});
const fields = {
username: {
input: document.getElementById('username'),
error: document.getElementById('username-error')
},
email: {
input: document.getElementById('email'),
error: document.getElementById('email-error')
},
password: {
input: document.getElementById('password'),
error: document.getElementById('password-error')
},
confirm_password: {
input: document.getElementById('confirm_password'),
error: document.getElementById('confirm-password-error')
}
}
var regForm = document.getElementById('register-form');
regForm.addEventListener('submit', async (e) => {
e.preventDefault();
const response = await fetch('/login', {
method: 'POST',
headers: {
'Content-Type': 'application/json'
},
body: JSON.stringify({
username: fields.username.input.value,
email: fields.email.input.value,
password: fields.password.input.value,
confirm_password: fields.confirm_password.input.value
})
});
if (response.ok) {
alert('yes');
console.log(response);
}
else {
const errors = await response.json();
Object.key(errors).forEach((key) => {
fields[key].input.classList.add('input-invalid');
fields[key].error.innerHTML = errors[key][0];
});
}
});<div class="form-container sign-up-container">
<form id="register-form" action="" method="POST">
{{ registerForm.hidden_tag() }}
<h1>Create an account</h1>
<fieldset class="uk-fieldset">
<div class="uk-margin form-group">
{% if registerForm.username.errors %} {{ registerForm.username(class="uk-input input-invalid") }}
<div class="input-erros" id="username-error">
{% for error in registerForm.username.errors %}
<span>{{ error }}</span> {% endfor %}
</div>
{% else %} {{ registerForm.username(class="uk-input") }} {% endif %}
</div>
<div class="uk-margin form-group" id="email-error">
{% if registerForm.email.errors %} {{ registerForm.email(class="uk-input input-invalid") }}
<div class="input-erros">
{% for error in registerForm.email.errors %}
<span>{{ error }}</span> {% endfor %}
</div>
{% else %} {{ registerForm.email(class="uk-input") }} {% endif %}
</div>
<div class="uk-margin form-group" id="password-error">
{% if registerForm.password.errors %} {{ registerForm.password(class="uk-input input-invalid") }}
<div class="input-erros">
{% for error in registerForm.password.errors %}
<span>{{ error }}</span> {% endfor %}
</div>
{% else %} {{ registerForm.password(class="uk-input") }} {% endif %}
</div>
<div class="uk-margin form-group" id="confirm-password-error">
{% if registerForm.confirm_password.errors %} {{ registerForm.confirm_password(class="uk-input input-invalid") }}
<div class="input-errors">
{% for error in registerForm.confirm_password.errors %}
<span>{{ error }}</span> {% endfor %}
</div>
{% else %} {{ registerForm.confirm_password(class="uk-input") }} {% endif %}
</div>
<div class="uk-margin form-group">
</div>
</fieldset>
<button class="form-button">Create an account</button>
</form>
</div>
<div class="form-container sign-in-container">
<form action="#">
<h1>Sign In</h1>
<fieldset class="uk-fieldset">
<div class="uk-margin">
{{ loginForm.usernameLogin(class="uk-input") }}
</div>
<div class="uk-margin">
{{ loginForm.passwordLogin(class="uk-input") }}
</div>
<div class="uk-margin">
{{ loginForm.submit(class="form-button") }}
</div>
</fieldset>
</form>
</div>
<div class="overlay-container">
<div class="overlay">
<div class="overlay-panel overlay-left">
<h1>Don't have an account yet?</h1>
<!-- <p>just sign in</p> -->
<button class="ghost form-button" id="signUp">Create an account</button>
</div>
<div class="overlay-panel overlay-right">
<h1>Already have an account?</h1>
<!-- <p>become a part of the community</p> -->
<button class="ghost form-button" id="signIn">Sign In</button>
</div>
</div>
</div>forms.py
class RegisterForm(FlaskForm):
username = StringField('username',
validators=[
DataRequired("username is required"),
Length(min=5,
max=15,
message="must be between 5 and 15 characters")
],
render_kw={"placeholder": "username"})
email = StringField('e-mail',
validators=[
DataRequired("e-mail is required"),
Email(message="probably not e-mail")
],
render_kw={"placeholder": "e-mail"})
password = PasswordField('password',
validators=[DataRequired("password is required")],
render_kw={"placeholder": "password"})
confirm_password = PasswordField('confirm password',
validators=[
DataRequired("confirm password"),
EqualTo('password')
],
render_kw={"placeholder": "confirm password"})
def validate_username(self, username):
pass
def validate_email(self, email):
pass
def validate_password(self, password):
pswd = password.data
flag = 0
while True:
if (len(pswd)<8):
flag = -1
break
elif not re.search("[a-z]", pswd):
flag = -1
break
elif not re.search("[A-Z]", pswd):
flag = -1
break
elif not re.search("[0-9]", pswd):
flag = -1
break
else:
flag = 0
break
if flag == -1:
raise ValidationError('the password is too simple')
When I submit the registration form it seems like only DataRequired validator works. Because I can put anything into email and password and I still get that 'yes' alert like the response is ok.
Validating a JSON request using WTForms is slightly different to handling a normal, urlencoded form request.
Here's simple example that uses the RegisterForm from the question.
# imports here
...
import wtforms_json
# Initialise wtforms_json
wtforms_json.init()
app = Flask(__name__)
app.config['SECRET_KEY'] = b'secret'
@app.route('/login', methods=['POST'])
def login():
# Get the JSON data from the request.
formdata = request.get_json()
# Create the form using the from_json constructor
registerForm = RegisterForm.from_json(formdata=formdata)
# Return a dict, which will automatically be serialised as JSON.
if registerForm.validate_on_submit():
return {'result': 'success'}
return registerForm.errors
app.run()
Notable features:
wtforms_json.init() must be called to add JSON features to the Form classIf this data is sent to the app, error validation is as expected:
$ cat register.json
{
"username": "Tharg",
"email": "Banana",
"password": "red",
"confirm_password": "blue",
"csrf_token": "secret"
}
$ curl -X POST -H "Content-Type: application/json" -d @register.json http://localhost:5000/login
{"confirm_password":["Field must be equal to password."],"csrf_token":["The CSRF token is missing."],"email":["probably not e-mail"],"password":["the password is too simple"]}