I need some clarification as to what the best practice is regarding this. So, say you have a Django form which has many fields that the user can fill out. Say you also have corresponding fields in the models file, but the models file contains some extra fields that the user cannot modify, e.g. unique reference number. Say also, you want to access these hidden fields in the views so that you can present this reference number to the user.
What's the best way of accessing these "hidden" fields that are created when a valid form is submitted? I was thinking of grabbing the latest entry by date, though if there's concurrent requests at the same time, the wrong data may be pulled?
Try using Django's HiddenInput widget. This will allow you to associate data with a form without allowing the user to modify it.
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I have a ManyToMany relationship between two Django Models: Team and Member. A single Member can be part of multiple teams. I am able to successfully bind a Form class to a CreateView, and, using the standard ModelMultipleChoiceField,can successfully save the Form using the save_m2m method.
However, the default widget for the field is not suitable for my user experience. Instead of using a picklist, I would like to create a separate select box for each number of selectable Members per team. For example, if the Team can have 7 Members, I would like to show 7 select boxes, rather than one pick list that a user selects 7 different objects from.
I understand I may not get a complete answer, but would appreciate any pointers on if I should be looking into overriding the Field with a custom MultiWidget, or if using an inline formset might be a more appropriate route. Or, something else...
At the end of the day, I ultimately decided to stick with a single ModelForm for the Create Team form. Within this ModelForm, I dynamically create the number of fields I will need for the number of Member per team, and have created a function within the form that yields those fields.
I perform validation on those fields within the generic clean method of the ModelForm. I use the yield method within the Template to control displaying the individual fields.
I am sure it is not the most Django-y approach, as many people seem to use inlineformsets in theory, but this worked and the code does not seem overly hacky or unmaintainable.
I have a User model with some fields. Some of them will require feedback, are they correctly filled (if not, specific message will be displayed on user profile).
The problem is, how to represent 'invalid' fields in database. My idea is to create another model (call it ExtUser) with OneToOneField to User. And ExtUser should have same fields' names as User, but their types will be all boolean, determining whether field is filled in correctly. For example, if User has a field called email:
email = models.CharField(max_length=100)
ExtUser would have following field:
email = models.BooleanField(default=False)
Here's a problem with this approach. How am I supposed to create fields in ExtUser? Of course I can create them manually, but that would be breaking of DRY principle, and I'm not going to do that. The question is, can I add fields to model dynamically, and have them in database (so I assume it would require to be called before migrate)?
I have django 1.8 and I don't want to use any external modules/libraries.
If someone has an another idea of how to represent that data in database, please add comment, not a reply - as this question is about creating fields dynamically.
You will need to do this manually.
Python does not disallow this behavior; you can take a look at this SO response on dynamically created classes, but Django will not be able to interpret the output. In particular, Django relies on the models to create the SQL tables for the application, and there is essentially no way for this to occur if you model is not statically defined.
In this case, I don't think you have to worry much about DRY; if you need a separate model with fields which happen to be related to, but different from, another model, I think it's probably ok.
Finally, I'm unsure what your goal is, but you could probably define some functions which can determine how "correct" the fields of the user are. This is how I would recommend solving this problem (if it applies).
I'm new in django and python. I want to have a form in one of my website's page. When user fills the data, i want to create an xml file with user input. so i need to access the user's data (form data) from views.py. I want to know am i allowed to only have form in html? if yes, how can i use it's data in views.py? i mean should i have always a class defined in forms.py that contains my form fields? If the second way is a rule, what should i do with templates(html)? (It means if i define my fields in a class in forms.py, should i redefine them in templates(html) too? and how can i use data in views.py)
i need some kinds of input in my form: checkbox, input type:text and input type:file
I really need your answers. Thank you :)
You can totally define your form in raw html and write a view which just processes the post data. But then we come to point where you would invent the wheel once again. Django provides a bunch of field classes which provide html rendering and data validation (never trust user input).
I suggest you read the online documentation for forms.
Django: what approaches are there to 'parametising' the display and editability of form fields.
I have several forms where I want some fields to be simply missing from the form display (dependent on the current user) and some fields to be uneditable, depending on the user.
This needs to be enforced on the server, so that a malicious user cannot break the security by manually constructing a post request with the missing parameter.
Likewise fields which are not displayed to the user, must still come back in the form results, so that fields which are not displayed to a user and not 'wiped-out' when the model is written back to the DB.
I also need to solve the same hiding problem for templates.
The app will have dozens of forms, with different immutability/hiding requirements, so this needs to be a generic system. Coding permissions inside each form would be too prone to error.
Any help appreciated.
Chris.
For hidding fields from form display, simple delete unneeded fields in form's __init__ method. Constructing post request by adding deleted fields, will not have influence on the form.
Regarding disabled or readonly fields, check this article and another question. Basically, cleaning field should set it to initial state.
I have an app where user submitted data needs to go through a verification process before it shows up on the site. At the moment this means they cannot edit the item without removing it from the site (so our admins can check it's okay).
I'd like to write another model where I can store revisions. Basically three fields where I store the date submitted, a boolean saying if the user is ready for that revision to be considered and a third where I store all the changes (as a pickled/JSON dict).
The problem I have at the moment is I don't want to bombard the admins with a complete listing each time. I only want them to see the changed fields. This means I need a way of generating a list of which fields have changed when the user submits the edit ModelForm so I only save this data in the revision.
There are probably several ways of doing this but my post-pub-quiz brain is slightly numb and can't think of the best way. How would you do it?
In terms of where this would go, I'd probably write it as an abstract ModelForm-inheriting class that other forms use. I'd override save() to stop it writing the data directly back to database (I'd want to redirect it through this fancy new revisions model).
Come to think of it, is there an app that already does this generically?