How do I get the data from a WTForms form after submitting it? I want to get the email entered in the form.
class ApplicationForm(Form):
email = StringField()
#app.route('/', methods=['GET', 'POST'])
def index():
form = ApplicationForm()
if form.validate_on_submit():
return redirect('index')
return render_template('index.html', form=form)
<form enctype="multipart/form-data" method="post">
{{ form.csrf_token }}
{{ form.email }}
<input type=submit>
</form>
Each field has a data attribute containing the processed data.
the_email = form.email.data
Working with form data is described in the getting started doc.
The most probable place for you to do things with the Form.attrs is in the index function. I have added some conditional guards on the method param. You want to do different things if they are using GET or POST as well. There are other ways to do all of this but I didn't want to change too much at once. But you should think about it clearly this way. If I have no form data because I've just made the initial request, I'm going to be using GET. Once I render the form in the template, I'm going to be sending a POST (as you can see in the top of your template). So I need those two cases dealt with firstly.
Then, once the form is rendered and returned I will have data or no data. So dealing with the data is going to happen in the POST branch of the controller.
#app.route('/index', methods=['GET', 'POST'])
def index():
errors = ''
form = ApplicationForm(request.form)
if request.method == 'POST':
if form.is_submitted():
print "Form successfully submitted"
if form.validate_on_submit():
flash('Success!')
# Here I can assume that I have data and do things with it.
# I can access each of the form elements as a data attribute on the
# Form object.
flash(form.name.data, form.email.data)
# I could also pass them onto a new route in a call.
# You probably don't want to redirect to `index` here but to a
# new view and display the results of the form filling.
# If you want to save state, say in a DB, you would probably
# do that here before moving onto a new view.
return redirect('index')
else: # You only want to print the errors since fail on validate
print(form.errors)
return render_template('index.html',
title='Application Form',
form=form)
elif request.method == 'GET':
return render_template('index.html',
title='Application Form',
form=form)
To help, I'm adding a simple example from some of my working code. You should be able to follow it given your code and my walk through.
def create_brochure():
form = CreateBrochureForm()
if request.method == 'POST':
if not form.validate():
flash('There was a problem with your submission. Check the error message below.')
return render_template('create-brochure.html', form=form)
else:
flash('Succesfully created new brochure: {0}'.format(form.name.data))
new_brochure = Brochure(form.name.data,
form.sales_tax.data,
True,
datetime.datetime.now(),
datetime.datetime.now())
db.session.add(new_brochure)
db.session.commit()
return redirect('brochures')
elif request.method == 'GET':
return render_template('create-brochure.html', form=form)
Related
MODELS.PY
class Campaign(models.Model):
user = models.ForeignKey(User, on_delete=models.CASCADE)
campaign_image = models.ImageField(default="profilepic.jpg",upload_to="campaign_pictures")
FORMS.PY
class RaiseFundsFrom3(forms.ModelForm):
class Meta:
model = Campaign
fields = ['campaign_image']
VIEWS.PY
#login_required
def raise_funds_medical_3(request):
if request.method == 'POST':
form = RaiseFundsFrom3(request.POST, request.FILES or None, instance=request.user)
if form.is_valid():
check = form.save(commit=False)
check.save()
return HttpResponse('form worked')
else:
form = RaiseFundsFrom3()
return render(request,'funds/raise_funds_medical_3.html',{'form':form})
URLS.PY
path('raise/medical/photo', views.raise_funds_medical_3, name="raise_funds_medical_3"),
raise_funds_medical_3.html
<form method="post" enctype="multipart/form-data">
{% csrf_token %}
<div class="form-group pt-2">
<small>Photo formats must be PNG / JPG / JPEG</small>
<input type="file" name="campaign_image" />
</div>
<button class="btn btn-lg button_bfg_blue" type="submit"> <small><b> NEXT </b></small> </button>
</form>
on form submit, i do not get any error, but image is not uploaded to the required folder.
however, in the raise_funds_medical_3 function within views.py, if i remove instance=request.user, the image gets uploaded but i get following error : NOT NULL constraint failed: funds_campaign.user_id
Your form is a ModelForm for a Campaign, so its instance needs to be a Campaign. Don't assign request.user as its instance!
Now, your form isn't including the user field which is required to save a Campaign, so you should assign that yourself in the view before saving to the database:
campaign = form.save(commit=False) # this gives your the form's instance
campaign.user = request.user # this assigns the user
campaign.save() # this commits to the database
Also you should handle the case where the form isn't valid. This is quite simple, just un-indent the last return in your view function, so that return render(...) is also called in case the form isn't valid.
Finally, instead of returning a response when the form is valid, it's good practice to redirect to another view. This way, when the user refreshes the page, the form isn't submitted again. Your final code should look like this:
#login_required
def raise_funds_medical_3(request):
if request.method == 'POST':
form = RaiseFundsFrom3(request.POST, request.FILES or None)
if form.is_valid():
check = form.save(commit=False)
check.user = request.user
check.save()
return redirect(<url_pattern>)
else:
form = RaiseFundsFrom3()
return render(request,'funds/raise_funds_medical_3.html',{'form':form})
Supplementary answer to dirkgroten's one
I have come to completely hate the conventional structuring of a Django Function-based View. They can be re-factored by inverting the validity test and adding one line so that one and only one instantiation of a form is present. The result is IMO far easier to read, and easily generalizes for a view displaying two or more forms.
def raise_funds_medical_3(request):
args = [request.POST, request.FILES or None] if request.method == "POST" else []
form = RaiseFundsFrom3(*args)
if request.method != "POST" or not form.is_valid():
# unbound form or form not valid
return render(request,'funds/raise_funds_medical_3.html',{'form':form})
# form is valid so do the processing and redirect
check = form.save(commit=False)
check.user = request.user
check.save()
return redirect(<url_pattern>)
If you want to process >1 form, the test becomes
if request.method != "POST" or any(
[ not form.is_valid(), not form2.is_valid(), ...]):
which forces evaluation of .is_valid() for all forms, even if the first was not valid, so that all the error messages are shown to the user.
In a complex business application, the processing of a successful form submission may be quite a few more lines of code than this simple example. Having it at the end, not indented, isolated from all the boilerplate save the return redirect(...), makes things much easier!
I want to reset the form after it validates. Currently the form will still show the previous data after it is submitted and valid. Basically, I want the form to go back to the original state with all fields clean. What is the correct to do this?
#mod.route('/', methods=['GET', 'POST'])
def home():
form = NewRegistration()
if form.validate_on_submit():
#save in db
flash(gettext(u'Thanks for the registration.'))
return render_template("users/registration.html", form=form)
The issue is that you're always rendering the form with whatever data was passed in, even if that data validated and was handled. In addition, the browser stores the state of the last request, so if you refresh the page at this point the browser will re-submit the form.
After handling a successful form request, redirect to the page to get a fresh state.
#app.route('/register', methods=['GET', 'POST'])
def register():
form = RegistrationForm()
if form.validate_on_submit():
# do stuff with valid form
# then redirect to "end" the form
return redirect(url_for('register'))
# initial get or form didn't validate
return render_template('register.html', form=form)
davidism answer is correct.
But once I had to reload a form with only a few fields that had to be resetted.
So, I did this, maybe it's not the cleanest way but it worked for me:
form = MyForm()
if form.validate_on_submit():
# save all my data...
myvar1 = form.field1.data
myvar2 = form.field2.data
# etc...
# at first GET and at every reload, this is what gets executed:
form.field1.data = "" # this is the field that must be empty at reload
form.field2.data = someobject # this is a field that must be filled with some value that I know
return render_template('mypage.html', form=form)
You can clear a form by passing formdata=None
#mod.route('/', methods=['GET', 'POST'])
def home():
form = NewRegistration()
if form.validate_on_submit():
#save in db
######### Recreate form with no data #######
form = NewRegistration(formdata=None)
flash(gettext(u'Thanks for the registration.'))
return render_template("users/registration.html", form=form)
you can also return new form object using render_template if form does not validates you can also pass message
#mod.route('/', methods=['GET', 'POST'])
def home():
form = NewRegistration()
if form.validate_on_submit():
#save in db
return render_template("user/registration.html", form = NewRegistration())
return render_template("users/registration.html", form=form)
I would like to pre-populate my form with data from my database to make necessary changes and modify my database with these changes.
However when i run the following code below, when the form.validate_on_submit() method is initialised, the form's data is the pre-populated data from the database and not the edited version. How do i access the edited value of the form data?
#auth.route('/edit_projects', methods=['GET', 'POST'])
#auth.route('/edit_projects/<project>', methods=['GET', 'POST'])
#login_required
def edit_projects(project=None):
form = ProjectForm()
project_db = Project.query.all()
edit_project_db = Project.query.filter_by(id=project).first()
if project != None:
form.name.data=edit_project_db.name
form.project_brief.data=edit_project_db.project_brief
form.project_description.data=edit_project_db.project_description
if form.validate_on_submit():
edit_project_db.name = form.name.data
edit_project_db.project_brief = form.project_brief.data
edit_project_db.project_description = form.project_description.data
db.session.commit()
flash('Product %s updated.' %(str(form.name.data)))
I think it could help to distinguish between 'GET' and 'POST', on 'GET' you prepopulate the fields, but on 'POST' you want to see if the user has actually edited the form content.
I would split the code like:
if request.method == 'GET':
# prepopulate
if project != None:
form.name.data=edit_project_db.name
form.project_brief.data=edit_project_db.project_brief
elif request.method == 'POST':
# check form validates
if form.validate_on_submit():
# keep the rest as it is
...
Hope this offers some help.
I have a survey form. After submitting the form, I'd like to handle saving the data then redirect to a "success" view. I'm using the following code right now, but it just stays on the current url, while I'd like to go to /success. How can I do this?
#app.route('/surveytest', methods=['GET', 'POST'])
def surveytest():
if request.method == 'GET':
return render_template('test.html', title='Survey Test', year=datetime.now().year, message='This is the survey page.')
elif request.method == 'POST':
name = request.form['name']
address = request.form['address']
phone = request.form['phone']
email = request.form['email']
company = request.form['company']
return render_template('success.html', name=name, address=address, phone = phone, email = email, company = company)
You have the right goal: it's good to redirect after handling form data. Rather than returning render_template again, use redirect instead.
from flask import redirect, url_for, survey_id
#app.route('/success/<int:result_id>')
def success(result_id):
# replace this with a query from whatever database you're using
result = get_result_from_database(result_id)
# access the result in the tempalte, for example {{ result.name }}
return render_template('success.html', result=result)
#app.route('/survey', methods=["GET", "POST"])
def survey():
if request.method == 'POST':
# replace this with an insert into whatever database you're using
result = store_result_in_database(request.args)
return redirect(url_for('success', result_id=result.id))
# don't need to test request.method == 'GET'
return render_template('survey.html')
The redirect will be handled by the user's browser, and the new page at the new url will be loaded, rather than rendering a different template at the same url.
Though I am not specifically answering your current question I found myself with a similar problem with getting the page to redirect after the submission button had been clicked. So I hope this solution could potentially work for others that find themselevs in a similar predicament.
This example uses Flask forms for handling forms and submissions.
from flast_wtf import FlaskForm
#app.route("/", methods=["GET", "POST"])
def home():
stock_form = StockForm()
tick = stock_form.text_field.data
if tick != None:
return redirect(f'/{tick}', code=302)
return render_template("home.html", template_form=stock_form, ticker=tick)
The if statement checks that the submission after being clicked has a value, then redirects to your chosen link. This code is a copy and paste from a badly programmed stock price lookup.
I am using the Flask-login's #login_required decorator for some routes in my app. When navigating to those routes while not logged in I am redirected to the login page. So far so good.
The redirected url looks like this: /login?next=%2Fusers
Looks like it url-encoded the next parameter, something I haven't seen in the examples I've run across. After logging in the redirect back to next is always failing and falling back to the index page. I think this is because next is url-encoded.
Should I be going about this a different way? I'm just starting to dive into the Flask framework and working off of examples so I don't know much about the best ways to do things.
Here's an example route:
login_manager.login_view = 'login'
#app.route('users')
#login_required
def users():
return 'Test'
And my login route looks like this:
#app.route('/login')
def login():
error = None
next = request.args.get('next')
if request.method == 'POST':
username = request.form['username']
password = request.form['password']
if authenticate_user(username, password):
user = User.query.filter_by(username=username).first()
if login_user(user):
flash("You have logged in")
session['logged_in'] = True
return redirect(next or url_for('index', error=error))
error = "Login failed"
return render_template('login.html', login=True, next=next, error=error)
Thanks in advance for the help.
I figured it out, navigating to a login-protected route (/requests in this example) would cause a redirect to the login page with the next parameter.
/login?next=%2Frequests
In my login template, I had this:
<form action="{{ url_for('login') }}" method='POST'>
This caused the form to be posted to the /login route without any parameters. Removing the action attribute or changing it to action="" causes the form to be posted to its own url, which includes the original query string. Another option would be including next=next in url_for.
<form action="{{ url_for('login', next=next) }}" method='POST'>
Here you go:
import urllib
#app.route('/login')
def login():
error = None
next = urllib.unquote_plus(request.args.get('next'))
...
In case anyone finds this question like I did, here was the implementation that worked for me. The issue was that the login's POST form was only going to /login, causing the next URL is get thrown away. Following Kevan's suggestion, if you add next=request.args.get('next')) to the login form's action, it will pass the next argument with it.
Inside my login function
#app.route('/login', methods = ['GET', 'POST'])
def login():
next = request.args.get('next')
if request.method == 'POST':
...Confirm User...
if next:
return redirect(next)
else:
return redirect('/')
Inside my login form
<form method="post" action="{{ url_for('login', next=request.args.get('next')) }}" enctype="multipart/form-data">
For security reasons, it should be considered the check for the next parameter, as suggested in
https://flask-login.readthedocs.io/en/latest/#login-example
#app.route('/login', methods=['GET', 'POST'])
def login():
# Here we use a class of some kind to represent and validate our
# client-side form data. For example, WTForms is a library that will
# handle this for us, and we use a custom LoginForm to validate.
form = LoginForm()
if form.validate_on_submit():
# Login and validate the user.
# user should be an instance of your `User` class
login_user(user)
flask.flash('Logged in successfully.')
next = flask.request.args.get('next')
# is_safe_url should check if the url is safe for redirects.
# See http://flask.pocoo.org/snippets/62/ for an example.
if not is_safe_url(next):
return flask.abort(400)
return flask.redirect(next or flask.url_for('index'))
return flask.render_template('login.html', form=form)