I am currently working on a web-application based "database-explorer" for a university project.
Basically I create a site for each relation of the database, where the user can view the data and additionally I want them to be able to add data.
For that I use wtforms. I take the inputs, create a simple "SQL string" with it and execute it.
To make the input easier, I want to use dynamic SelectFields.
This is my approute:
#app.route('/table/fact_angestellte')
def fact_angestellte():
if current_user.is_authenticated:
mycursor.execute("SELECT * FROM dim_rolle WHERE ro_rolle !='Ansprechpartner' AND ro_rolle != 'Teilnehmer';")
choicesRolle = mycursor.fetchall()
form = InsertAngestelltenForm(choicesRolle)
print(form.choicesRolle)
mycursor.execute("SELECT * FROM fact_angestellte INNER JOIN dim_rolle ON fact_angestellte.an_rolle_fk = dim_rolle.ro_id_pk;")
data = mycursor.fetchall()
return render_template('tables/fact_angestellte.html', data=data, form=form)
else:
return redirect(url_for('login'))
The form gets created successfully and if I try to print form.choicesRolle (in the approute), it also gives me the correct output in the console. But when I go on my website, the SelectField still has the default value of choicesRolle.
class InsertAngestelltenForm(FlaskForm):
choicesRolle =[]
nachname = StringField('Nachname', validators=[DataRequired()])
vorname = StringField('Vorname',validators=[DataRequired()])
geschlecht = SelectField('Geschlecht', choices=[('maennlich', 'männlich'), ('weiblich', 'weiblich')], validators=[DataRequired()])
postleitzahl = StringField('Postleitzahl | FK', validators=[DataRequired()])
strasse = StringField('Straße und Nummer', validators=[DataRequired()])
rolle = SelectField('Rolle', choices=choicesRolle, validators=[DataRequired()])
submit = SubmitField('Eintrag hinzufügen')
def __init__(self, choicesRolle):
super().__init__()
self.choicesRolle = choicesRolle
print(self.choicesRolle)
So my problem is: the object has the correct attributes, but somehow they don't "reach" the template.
Any help is appreciated.
Greetings
Per the WTForms documentation, the choices keyword is only evaluated once. In your example, this means it's evaluating to the empty array you set in the choicesRolle class attribute, and that's what's being passed to Flask. You need to set the choices after the form is instantiated, not during it.
On your form class, remove the entire __init__ method, the choicesRolle class attribute, and the choices parameter from the rolle SelectField. Then, in your fact_angestellte view function, set the form's choices after you instantiate it, as follows:
choicesRolle = mycursor.fetchall()
form = InsertAngestelltenForm()
form.rolle.choices = choicesRolle
This should work...let me know. Note that I'm not sure what data is being returned from mycursor.fetchall() as you don't really describe, but the SelectField choices needs to be a list of values...WTForms by default coerces each value to unicode.
Related
I am developing an application using django where the UI needs to be updated when user interacts with it. For instance I have a Drop down field where the user selects a drink and submits it then based on that a dropdown with the places that drink is available, price and quantity at each place needs to be displayed. The user will then further submit the form for second process.
From my understanding the Forms in django are pre-defined and I am not able to think of a way using which I could achieve this.
What I could come up was defining a regular form class
class dform(forms.Form):
SOURCES_CHOICES = (
(A, 'A'),
(E, 'E'),
)
drink = forms.ChoiceField(choices = SOURCES_CHOICES)
location = forms.ChoiceField(choices = **GET THIS FROM DATABASE**)
quantity = forms.ChoiceField(choices = **GET THIS FROM DATABASE**)
.
.
.
My view is like,
def getdrink():
if request.method == 'POST':
#code for handling form
drink = dform.cleaned_data['drink']
#code to get values from database
I have no idea how to generate or populate or append the values i get from the database to the choicefield in my form. I did try looking up on SO but none of the solutions here explained properly how to do it. Also, due to certain requirements I am not using the models. So my database is not at all related to the models.
I am at a total loss Please help me out
class MyForm(forms.Form):
my_choice_field = forms.ChoiceField(choices=MY_CHOICES)
So if you want the values to be dynamic(or dependent of some logic) you can simply modify your code to something like this:
either
def get_my_choices():
# you place some logic here
return choices_list
class MyForm(forms.Form):
my_choice_field = forms.ChoiceField(choices=get_my_choices())
or
User_list = [ #place logic here]
class MyForm(forms.Form):
my_choice_field = forms.ChoiceField(choices=get_my_choices())
but once database value is updated, new data value will be popoulated only on restart of server.
So write a function like this in forms:
class MyForm(forms.Form):
def __init__(self, *args, **kwargs):
super(MyForm, self).__init__(*args, **kwargs)
self.fields['my_choice_field'] = forms.ChoiceField( choices=get_my_choices() )
or in place of the get_my_choices u can ad the USER_LIST too.
If you have models for location and quantity, a ModelChoiceField should work:
class dform(forms.Form):
location = forms.ModelChoiceField(queryset = Location.objects.all())
Otherwise, you'll need to query the database directly, for example:
class dform(forms.Form):
location = forms.ChoiceField(choices = get_location_choices())
# elsewhere
from django.db import connection
def get_location_choices():
cursor = connection.cursor()
cursor.execute("select location_id, name from location_table")
return cursor.fetchall()
The SQL query to use here depends on your database engine and table schema.
I think that, based on my understanding of your question, the best solution would be to include JSON objects with your form and load these using jQuery instead of submitting the form over and over. Included in your form, you should add something like:
class MyForm(forms.Form):
CHOICE_DICT = {
'choice_1': [
'option_1',
'option_2',
],
etc...
Then you should include form.CHOICE_DICT in your context, load that with jQuery, and render it depending on changes to other fields.
I'm currently working with django project. I had to filter the data store on the database based on the user input on form (at template) as looked below.
On form user either enter value or leave it blank. So what I have to do is first find the (valid) user input and then fire appropriate query to display data as user input in the form. So final result should be displayed on table at template.
As I'm new to django, how should I have to pass the data and fire query to represent data at multiple field. As help or link related to these type problem are expected. ( I just able to filter from the database with only one form and had no concept to solve this.)
Model of my temp project is as below.
class exReporter(models.Model):
first_name = models.CharField(max_length=30)
last_name = models.CharField(max_length=30)
email = models.EmailField()
gender = models.CharField(max_length=1)
age = models.IntegerField()
label = models.IntegerField()
There are a number of approaches you can take, but here is one solution you can use that involves chaining together the appropriate filters based on the form's posted data:
*Note: To conform to Python's naming convention, rename exReporter class to ExReporter.
# views.py
def process_ex_reporter_form(request):
if request.method == "POST":
# ExReporterForm implementation details not included.
ex_reporter_form = ExReporterForm(request.POST)
if ex_reporter_form.is_valid():
# If form field has no data, cleaned data should be None.
gender = ex_reporter_form.cleaned_data['gender']
age_start = ex_reporter_form.cleaned_data['age_start']
age_end = ex_reporter_form.cleaned_data['age_end']
aggregation_group = ex_reporter_form.cleaned_data['aggregation_group']
aggregation_id = ex_reporter_form.cleaned_data['aggregation_id']
ex_reporters = ExReporter.objects.get_ex_reporters(gender, age_start,
age_end, aggregation_group, aggregation_id)
else:
# Pass back form for correction.
pass
else:
# Pass new form to user.
pass
# models.py
class ExReporterManager(models.Manager):
def get_ex_reporters(self, gender, age_start, age_end, aggregation_group,
aggregation_id):
ex_reporters = super(ExReporterManager, self).get_query_set().all()
# Even though the filters are being applied in separate statements,
# database will only be hit once.
if ex_reporters:
if gender:
ex_reporters = ex_reporters.filter(gender=gender)
if age_start:
ex_reporters = ex_reporters.filter(age__gt=age_start)
if age_end:
ex_reporters = ex_reporters.filter(age__lt=age_end)
# Apply further filter logic for aggregation types supported.
return ex_reporters
I am trying to create a custom cleaning method which look in the db if the value of one specific data exists already and if yes raises an error.
I'm using a model form of a class (subsystem) who is inheriting from an other class (project).
I want to check if the sybsystem already exists or not when i try to add a new one in a form.
I get project name in my view function.
class SubsytemForm(forms.ModelForm):
class Meta:
model = Subsystem
exclude = ('project_name')
def clean(self,project_name):
cleaned_data = super(SubsytemForm, self).clean(self,project_name)
form_subsystem_name = cleaned_data.get("subsystem_name")
Subsystem.objects.filter(project__project_name=project_name)
subsystem_objects=Subsystem.objects.filter(project__project_name=project_name)
nb_subsystem = subsystem_objects.count()
for i in range (nb_subsystem):
if (subsystem_objects[i].subsystem_name==form_subsystem_name):
msg = u"Subsystem already existing"
self._errors["subsystem_name"] = self.error_class([msg])
# These fields are no longer valid. Remove them from the
# cleaned data.
del cleaned_data["subsystem_name"]
return cleaned_data
My view function :
def addform(request,project_name):
if form.is_valid():
form=form.save(commit=False)
form.project_id=Project.objects.get(project_name=project_name).id
form.clean(form,project_name)
form.save()
This is not working and i don't know how to do.
I have the error : clean() takes exactly 2 arguments (1 given)
My model :
class Project(models.Model):
project_name = models.CharField("Project name", max_length=20)
Class Subsystem(models.Model):
subsystem_name = models.Charfield("Subsystem name", max_length=20)
projects = models.ForeignKey(Project)
There are quite a few things wrong with this code.
Firstly, you're not supposed to call clean explicitly. Django does it for you automatically when you call form.is_valid(). And because it's done automatically, you can't pass extra arguments. You need to pass the argument in when you instantiate the form, and keep it as an instance variable which your clean code can reference.
Secondly, the code is actually only validating a single field. So it should be done in a specific clean_fieldname method - ie clean_subsystem_name. That avoids the need for mucking about with _errors and deleting the unwanted data at the end.
Thirdly, if you ever find yourself getting a count of something, iterating through a range, then using that index to point back into the original list, you're doing it wrong. In Python, you should always iterate through the actual thing - in this case, the queryset - that you're interested in. However, in this case that is irrelevant anyway as you should query for the actual name directly in the database and check if it exists, rather than iterating through checking for matches.
So, putting it all together:
class SubsytemForm(forms.ModelForm):
class Meta:
model = Subsystem
exclude = ('project_name')
def __init__(self, *args, **kwargs):
self.project_name = kwargs.pop('project_name', None)
super(SubsystemForm, self).__init__(*args, **kwargs)
def clean_subsystem_name(self):
form_subsystem_name = self.cleaned_data.get("subsystem_name")
existing = Subsystem.objects.filter(
project__project_name=self.project_name,
subsytem_name=form_subsystem_name
).exists()
if existing:
raise forms.ValidationError(u"Subsystem already existing")
return form_subsystem_name
When you do form=form.save(commit=False) you store a Subsystem instance in the variable form but the clean method is defined in SubsystemForm. Isn't it?
I have a page to insert value to db.
After inserting am loading another page with a drop down listing the db values
But the inserted value is not listing in dropdown
The problem is not with transaction/commit etc. The query to retrieve the data for the drop down in second form is correct.
Form1(first page)
class Organization(forms.Form):
orgList = getOrgUnitList()
orgUnit = forms.CharField(label=u'Organization Name',
max_length=50,
error_messages={'required':'Organization name is required field.'})
parentOrg= forms.ChoiceField(label=u'Parent Organization',
choices=[(u'Select',u'Select')]+orgList,
error_messages={'required':'Organization name is required field.'})
Form2(Second page)
class User(forms.Form):
orgUnitList = getOrgUnitList()
email = forms.EmailField(label=u'Email',
max_length=50,
error_messages={'required':'Email is required field'})
orgUnit = forms.ChoiceField(label=u'Organizational Unit',
choices=orgUnitList,
error_messages={'required':'Organizational unit is required field'})
Query
def getOrgUnitList():
orgUnitList = list(OrganizationUnit.objects.values_list
('OrgUnitID','OrgUnitName').order_by('OrgUnitName'))
return orgUnitList
but when i tried to bind the choices in view it is working
working code
*view*
def user()
template = get_template('AddUser.html')
form = AddUser()
orgUnitList = getOrgUnitList()
del objAdminUIDA
form.fields['orgUnit'].widget.choices=orgUnitList
variables = RequestContext(request,{'form':form})
output = template.render(variables)
del form
return HttpResponse(output)
But i cant give the dropdown choice in view i want to give choices in form.i need a solution for form2
Firstly, the orgList is evaluated in form definition, that's why choices don't change. You should place getOrgUnitList in form's __init__ (or in some other method).
Secondly, you don't pass any data to the form, may be you want
form = AddUser(request.POST or None)
I am trying to access data.get_age_display in my email template. I can't seem to get the display of this. I am not sure what I am doing wrong, I've using get_FIELD_display numerous times before but passed as context to a normal template. Is there something different with forms?
class RequestForm(forms.Form):
ADULT = 1
SENIOR = 2
STUDENT = 3
AGE_GROUP = (
(ADULT, 'Adult'),
(SENIOR, 'Senior'),
(STUDENT, 'Student'),
)
name = forms.CharField(max_length=255)
phone = forms.CharField(max_length=15)
age = forms.ChoiceField(choices=AGE_GROUP)
details = forms.CharField(widget=forms.Textarea())
def save(self):
order = Order(
name = self.cleaned_data['name'],
phone = self.cleaned_data['phone'],
age = self.cleaned_data['age'],
details = self.cleaned_data['details'],
)
order.save()
template = loader.get_template('request_email.txt')
# send over the order object in an email extracted so they can handle the ticket order
context = Context({
'data': order,
})
#import pdb; pdb.set_trace()
email_subject = 'Request Tickets'
mail_managers(email_subject, template.render(context))
in my request_email.txt all I am doing is {{ data.get_age_display }} any ideas?
Jeff
You haven't shown the code for the Order model that you're creating. Are you sure that the age field on the model has choices set?
Any reason you're not using a ModelForm? You're creating an Order object within the form's save() method, but not returning it. A modelform would do that for you, as well as removing the need to redeclare the fields for the form.
I know this is coming WAAAAAY later than the question being posted but here's my answer for completeness and anyone else who might benefit from it :-)
I'm going to assume that in AGE_GROUP, ADULT, SENIOR and STUDENT are integers. Your form cleaning will NOT automatically clean the string contained in the POST and return an integer. So in this code:
context = Context({
'data': order,
})
you would think order.age is referring to an integer but that is, in fact, incorrect. It's burned me a few times before because this will correctly save the integer to the physical table, but the order instance still has the string representation of the age field.
You could do one of two things:
1. Clean this in the field:
clean_age(self):
return int(self.cleaned_data['age'])
or create a new field type:
def MyChoiceField(forms.ChoiceField):
def clean(self, value):
if not value:
if self.required:
raise forms.ValidationError(self.error_messages['required'])
return None
else:
return None
return int(value)
link that to the form field:
age = MyChoiceField(choices=AGE_GROUP)
and then you'll be able to apply this logic to any other such choice field in future. Personally, I find the latter approach the best one and I stick all my custom field types into a form_utils file so that I can use them everywhere. Another gotcha is that forms.charField doesn't automatically strip the entered text and you can use this approach to fix that too.