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Flask - commit FieldList to database using SQLAlchemy?

I am trying to commit fields generated from a FiedList but getting the error:
AttributeError: 'str' object has no attribute 'data'
What I'm trying to do is add a list of fields to the database which I can then retrieve and display on the page.
#App.py
#app.route('/', methods=['GET', 'POST'])
def index():
form = MainSubscriptionForm()
if form.validate_on_submit():
for x in form.subscription:
sub = Subscription(company=x.company.data, description=x.description.data)
db.session.add(sub)
db.session.commit()
elif request.method == 'GET':
list = Subscription.query.all()
return render_template('index.html', title="Home", form=form, list=list)
#forms.py
class SubscriptionForm(FlaskForm):
company = StringField(('Company'), validators=[DataRequired(), Length(min=0, max=20)])
description = StringField(('Description'), validators=[Length(min=0, max=120)])
save = SubmitField('Save')
class MainSubscriptionForm(FlaskForm):
subscription = FieldList(FormField(SubscriptionForm), min_entries=1)
#models.py
class Subscription(db.Model):
id = db.Column(db.Integer, primary_key=True)
company = db.Column(db.String(20))
description = db.Column(db.String(120))
#index.html
{% extends "base.html" %}
{% from 'bootstrap/form.html' import render_form_row %}
{% block content %}
<form method="post">
{{ form.csrf_token() }}
{% for sub in form.subscription %}
{{ render_form_row(sub) }}
{% endfor %}
</form>
{{ list }}
{% endblock %}

The issue was that a dictionary was being sent and therefore it was crashing on the below line:
sub = Subscription(company=x.company.data, description=x.description.data)
The solution was to get the key value as per below:
sub = Subscription(company=x.data['company'], description=x.data['description'])

Form isn't validating despite having a csrf token

I have seen a few similar questions here, but none of the solutions seem to apply here(the problem is usually that it lacks a csrf token, which is not the case here).
I have a form with four fields- 3 drop down lists with SelectField and one StringField- built using flask wtforms. I tried adding an edit feature to this, which uses the same HTML template, but this it isn't getting validated(not entering the form.validate_on_submit section). This is the code for the function:
#app.route('/movements/<int:movement_id>/edit', methods=['GET', 'POST'])
def edit_movement(movement_id):
movement = Movement.query.get_or_404(movement_id)
form = MovementForm()
if form.validate_on_submit():
product = Product.query.filter_by(id=form.product.data).first()
from_location = Location.query.filter_by(id=form.from_location.data).first()
to_location = Location.query.filter_by(id=form.to_location.data).first()
if int((Balance.query.filter_by(product = product.name).filter_by(location = from_location.name).first()).balance) < int(form.quantity.data) and from_location.name != "":
flash("Invalid movement. Quantity of the product is insufficient.")
else:
movement.product_id = product.id
movement.product = product.name
movement.from_location_id = from_location.id
movement.from_location = from_location.name
movement.to_location_id = to_location.id
movement.to_location = to_location.name
movement.quantity = form.quantity.data
db.session.commit()
flash('The product movement has been edited!', 'success')
return redirect(url_for('movements'))
elif request.method == 'GET':
form.product.choices = [(product.id,product.name) for product in Product.query.all()]
form.from_location.choices = [(location.id,location.name) for location in Location.query.all()]
form.to_location.choices = [(location.id,location.name) for location in Location.query.all()]
form.quantity.data = movement.quantity
edit_button = True
return render_template('movements.html',form=form, edit_button=edit_button)
This is the code for the form:
class MovementForm(FlaskForm):
product = SelectField("Product", choices = [])
from_location = SelectField("From Location", choices = [], coerce=int)
to_location = SelectField("To Location", choices = [], coerce=int)
quantity = StringField("Quantity", validators=[DataRequired()])
add_movement = SubmitField("Add Movement")
And this is the model for the table:
class Movement(db.Model):
id = db.Column(db.Integer, primary_key=True)
product_id = db.Column(db.Integer, db.ForeignKey('product.id'), nullable=False)
product = db.Column(db.String(50), nullable=False)
from_location_id = db.Column(db.Integer, db.ForeignKey('location.id'))
from_location = db.Column(db.String(50))
to_location_id = db.Column(db.Integer, db.ForeignKey('location.id'))
to_location = db.Column(db.String(50))
quantity = db.Column(db.Integer, nullable=False)
timestamp = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
The HTML code for the form:
<form action="" method="POST">
{{ form.csrf_token }}
{{ form.product.label }}
{{ form.product }}
{{ form.from_location.label }}
{{ form.from_location }}
{{ form.to_location.label }}
{{ form.to_location }}
{{ form.quantity.label }}
{{ form.quantity }}
{% if edit_button %}
<input type="submit" value="Edit Movement">
{% else %}
{{ form.add_movement }}
{% endif %}
</form>

validate_on_submit is a convenient function that combines a check for whether the form was submitted (i.e., a POST, PUT, PATCH, or DELETE) with call to form.validate. If validation fails, the dictionary held byform.errors will get populated with useful information.
A useful step to debug your problem would be to log (print) the contents of form.errors if validate_on_submit returns False.

The form.errors in your code is as follows:
{'product': ['Not a valid choice'], 'from_location': ['Not a valid choice'], 'to_location': ['Not a valid choice']}
So it is reasonable for the validate_on_submit to return False.
If you comment out these fields and leave only the quantity it should work. The following changes worked for me and I managed to update the quantity in the DB. If it works also for you then you could try to uncomment each field and debug further.
Change the form to:
class MovementForm(FlaskForm):
quantity = StringField("Quantity", validators=[DataRequired()])
add_movement = SubmitField("Add Movement")
and the route to:
#app.route('/movements/<int:movement_id>/edit', methods=['GET', 'POST'])
def edit_movement(movement_id):
movement = Movement.query.get_or_404(movement_id)
form = MovementForm()
if form.validate_on_submit():
movement.quantity = form.quantity.data
db.session.commit()
flash('The product movement has been edited!', 'success')
return redirect(url_for('movements'))
elif request.method == 'GET':
form.quantity.data = movement.quantity
print(form.errors)
edit_button = True
return render_template('movements.html', form=form, edit_button=edit_button)
Change the template to:
<form action="" method="POST">
{{ form.csrf_token }}
{{ form.quantity.label }}
{{ form.quantity }}
{% if edit_button %}
<input type="submit" value="Edit Movement">
{% else %}
{{ form.add_movement }}
{% endif %}
</form>
Update:
The issue you are facing is described here.
Please try the following and if it works as expected then set similarly the remaining fields (it worked for me and I managed to update the quantity and the from_location/id in the DB):
the form:
class MovementForm(FlaskForm):
fromloc = [(location.id,location.name) for location in Location.query.all()]
from_location_id = SelectField("From Location ID", choices = fromloc, coerce=int)
quantity = StringField("Quantity", validators=[DataRequired()])
add_movement = SubmitField("Add Movement")
the route:
#app.route('/movements/<int:movement_id>/edit', methods=['GET', 'POST'])
def edit_movement(movement_id):
movement = Movement.query.get_or_404(movement_id)
form = MovementForm()
if form.validate_on_submit():
movement.from_location_id = form.from_location_id.data
movement.from_location = (Location.query.filter_by(id = form.from_location_id.data).first()).name
movement.quantity = form.quantity.data
db.session.commit()
flash('The product movement has been edited!', 'success')
return redirect(url_for('movements'))
elif request.method == 'GET':
form.from_location_id.choices = [(location.id,location.name) for location in Location.query.all()]
form.quantity.data = movement.quantity
print(form.errors)
edit_button = True
return render_template('movements.html', form=form, edit_button=edit_button)
the template:
<form action="" method="POST">
{{ form.csrf_token }}
{{ form.from_location_id.label }}
{{ form.from_location_id }}
{{ form.quantity.label }}
{{ form.quantity }}
{% if edit_button %}
<input type="submit" value="Edit Movement">
{% else %}
{{ form.add_movement }}
{% endif %}
</form>

I'm still not quite sure why my form wasn't validating, but my function started working after I replaced if form.validate_on_submit() with if request.method == 'POST'.

form.as_hidden doesn't pass values to POST

My form has initial values in it. I use form.as_hidden to hide the values and pass those values through a POST request. However, the hidden values are not passing through. Is there a way through this?
views.py
def car_detail_view(request, id):
if request.method == "POST":
form = CarForm(request.POST)
print(form.is_valid())
if form.is_valid():
car_save = form.instance
get_car = Car.objects.get(number_plate=car_save.number_plate)
get_car.available = False
get_car.save()
return redirect('/')
else:
print(form.errors)
else:
car = Car.objects.get(id=id)
form = CarForm(initial={'brand':car.brand, 'number_plate':car.number_plate, 'price':car.price,
'available':car.available})
args = {
'car':car,
'form':form
}
return render(request, 'map/confirmation.html', args)
confirmation.html
<h1>Confirmation of Booking</h1>
{% block content %}
<p>Brand: {{ car.brand }}</p>
<p>Number Plate: {{ car.number_plate }}</p>
<p>Price: {{ car.price }}</p>
<p> Are you sure you want to book? <p>
<form class="" method="post">
{% csrf_token %}
{{ form.as_hidden }}
<input type="submit" value="Book {{ car.brand }}">
</form>
{% endblock %}
Error
<ul class="errorlist"><li>brand<ul class="errorlist"><li>This field is required.</li></ul></li><li>number_plate<ul class="errorlist"><li>This field is required.</li></ul></li><li>price<ul class="errorlist"><li>This field is required.</li></ul></li></ul>

Django doesn't have a form.as_hidden method. Therefore {{ form.as_hidden }} will render as the empty string '' in your template.
You can use the as_hidden method for individual form fields.
{{ form.number_plate.as_hidden }}
If you use values from hidden fields, you might need to add code to prevent the user altering the field values (e.g. with their browser's developer tools). However, in your case you don't need to get the values from the form, you can fetch them from the database.
def car_detail_view(request, id):
if request.method == "POST":
car = Car.objects.get(id=id)
car.available = False
car.save()
return redirect('/')
else:
car = Car.objects.get(id=id)
args = {
'car':car,
}
return render(request, 'map/confirmation.html', args)
Once you've got this working, you might want to think about what happens if two users try to book the same car at once.

Django update model entry using form fails

I want to update a model entry using a form. the problem is that instead of updating the entry it creates a new entry.
def edit(request, c_id):
instance = get_object_or_404(C, id=int(c_id))
if request.POST:
form = CForm(request.POST, instance=instance)
if form.is_valid():
form.save()
return redirect('/a/b', c_id)
else:
form = CForm(instance=instance)
args = {}
args.update(csrf(request))
args['form'] = form
args['c_id'] = c_id
return render_to_response('a/b.html', args)
HTML code:
<form action="/a/edit/{{ c_id }}/" method="post">
{% csrf_token %}
{% for field in form %}
<div class="fieldWrapper">
{{ field.errors }}
{{ field.label_tag }} {{ field }}
{% if field.help_text %}
<p class="help">{{ field.help_text|safe }}</p>
{% endif %}
</div>
{% endfor %}
<input type="submit" value="Submit"/>
</form>
CForm class code
class CForm(forms.ModelForm):
class Meta:
model = C
fields = ['name', 'code']

You're checking the request for a POST method incorrectly. request.POST isn't a boolean, it contains a dictionary of post variables and is always going to have the CSRF token in it so it will always be "truthy". What you need is request.method.
Instead of:
if request.POST:
Replace it with:
if request.method == "POST":

Can Dynamic number of formset be used in a single view and passed o a single Template

I have the following view,template and form through which i am implementing the formset. I intend to implement multiple formsets in a single view/template but my number of formsets is dynamic based on user input. How can i have multiple dynamic number of formsets in this code?
Can i do this with dictionary element i.e by creating a dictionary of formsets??
My view is as follows:
def show (request):
b = request.session["s1"] # count of no of period ids
c = request.session["s2"] # account number inserted by user
d = request.session["s3"] # year inserted by customer
a = account_period.objects.filter(year=d).values('id')
e = account_period.objects.filter(year=d).values('month')
f = account_period.objects.filter(id = a).values('year')
butt = formset_factory(bu, extra=b)
if request.method == 'POST'
formset = butt(request.POST)
if formset.is_valid():
z = account_tab.objects.get(account_number=c)
pr = date.today()
i=0
for form in formset.forms:
x = form.cleaned_data['value']
y = account_period.objects.get(id=a[i:(i+1)])
try:
uip = budget.objects.get(account_no = c,account_period = a[i:(i+1)])
if uip.budget_amount != x
uip.budget_amount = x
uip.save()
except budget.DoesNotExist:
w = budget(account_no = z, account_period = y, budget_amount = x, created_by_login = 'me')
w.save()
i=i+1
pass
return HttpResponse('thanks')
form is
class bu(forms.Form):
value = forms.CharField()
template is
<html>
<head>
<title>BUDGET</title>
</head>
<body>
<p>BUDGET MANAGEMENTS</p>
<p>Your Account Number is : {{ account_number }}.</p> <p>You Chose {{ period }} {{month}} as period<p>
{% if form.errors %}
<p style="color: red;">
Please correct the error{{ form.errors|pluralize }} below.
</p>
{% endif %}
<form action="." method="post">{% csrf_token %}
{{ formset.management_form }}
<table>
{% for form in formset.forms %}
{{ form }}
{% endfor %}
</table>
<input type="submit" value="Submit">
</form>
</body>
</html>
#
#rohan
my GET method return has many variables which has to be passed into template so i tried to pass the dictionary formsetlist (after appying the changes u suggested) in following 2ways
1)
formset = butt( return render_to_response('budgetfinalform.html', {'account_number': c,'period':d,'month':e,'year':f,'formset': formset},context_instance=RequestContext(request))
2)
ctx ={'formsetlist': formset}
formset = butt( return render_to_response('budgetfinalform.html', {'account_number': c,'period':d,'month':e,'year':f,ctx,context_instance=RequestContext(request))
but obtained "unboundlocalerror : local variable 'formset' referenced before assignment"

I would do something like:
def show (request):
#initial view processing
# fomset_count taken as parameter or user input
formsetlist = []
#create formset list
for i in range(0, formset_count):
formsetlist.append(formset_factory(bu, extra=b))
# other view related code
# for GET method
ctx = { 'formsetlist': formset }
return render_to_response('your_template_name', ctx,
context_instance = RequestContext(request)
)
In template:
<form action="." method="post">{% csrf_token %}
{% for formset in formsetlist %}
{{ formset.management_form }}
<table>
{% for form in formset.forms %}
{{ form }}
{% endfor %}
</table>
{%endfor%}
<input type="submit" value="Submit">