Django Wagtail dynamically create form without new model - python-3.x

How would I allow my primary user to dynamically create forms they can issue to their end clients. Each of my primary users has their own unique information they would like to collect that I do not know before hand. I would like to avoid creating new models in code for their dynamic needs and then having to migrate the models.
I came across this which had an interesting response but it starts with disclaimer
The flexibility of Python and Django allow developers to dynamically create models to store and access data using Django’s ORM. But you need to be careful if you go down this road, especially if your models are set to change at runtime. This documentation will cover a number of things to consider when making use of runtime dynamic models.
Which leads me to believe a lot can go wrong.
However because I'm using wagtail I believe there is probably a way to use StructBlocks & StreamFields to accomplish it.
Any guidance would be helpful.

Wagtail provides a form builder module for this purpose.

I have two possible solutions for you, although it should be said that there is probably some library with Django that I don't know about that does this, but that being said.
Prompt your user for which fields they want and the field type.
Pass this as a dictionary to some function that would generate the HTML code for the form.
When this form is used, instead of worrying about storing the fields seperately, store a dictionary in the Models. There are two ways to do that here
Another way that you could do this, albeit more convoluted but more suited to your needs, is to use MongoDB for the database for Django instead. Because it is unstructured, it might be better suited for your use case. Instructions on using MongoDB for Django are here

Related

Best way to convert query results to domain entities

I am using Knex.js to build SQL queries. It works well but I need to convert my query results into domain entities (a type representing an object from the domain) for my graphql resolvers. I used Knex to avoid using an ORM because a number of people online made it seem like an ORM will make queries more difficult. My current best idea is to follow the Repository pattern and have the ugly code for converting results to classes in the repo class. Better ideas are welcome :)
As I understood you want to just make a db-call based on GraphQL query (which is mean you already have db and want to use simple ORM instead of EF for example).
I don't know which platform do you have, but if you have .net, you can take a look NReco.GraphQL. It allows to set db-connection and define graphql schema in the json file (graphql schmea to db-table including relation between schemas), definately, it's worth take a look.

Are the new fields on Processes and Tasks in Viewflow 1.6.0 for library users, or for internal use only

Viewflow 1.6.0 introduces new fields ("data" is a JSON field, and "artifact" support for a generic foreign key). They are present on both Processes and Tasks.
Are these intended to be available to library users, or are they Viewflow internal-use-only? I did not see anything in the docs or the github issues list to clarify the matter, so a pointer would be appreciated if I missed it.
Yep, it's for library users, that allows using proxy models instead of real tables for keeping process-only data
Data field is the JSON. So it could be used with jsonstore field - https://github.com/viewflow/jsonstore that makes JSON data exposed as a real Django field. So it could be used with ModelForms as usual
Ex: https://github.com/viewflow/viewflow/blob/master/demo/helloworld/models.py#L6
Articact allow to link process and your data models, without creating a separate table for that.
All of those allow avoiding joins to build all tasks from different flows for a user.

MEAN Stack: static list best practice

This is a general best practice question:
I am building a MEAN (mongo, express, angular, node) website. I have a user object that can have a gender [Mr or Miss] and a city [Paris, New York, Anything]
So this is quite a common problem: where should I store those lists that rarely change and never exceed, let's say, 50 rows.
1/ Is it better to have them stored in the database (mongo) with a foreign key in the user table. And so I have a gender table and a city table. But everytime I access these lists I need to read the base?
2/ Is it better to have them store in a file or in a controller? But this is a bit dangerous I think.
3/ Maybe there is another way that I don't know about.
I am not sure what is the best solution.
Are you concerned about an extra database call to get a list out?
If it was me I'd pick option 1 and I'd be storing it in a database. If you store value descriptions only front-end you'll run the risk of discrepancies if you end up updating your database's foreign keys but forget to update your controller or file and it seems rather untrustworthy. It also makes it more difficult to provide internationalization, because you'll have to start storing names and genders in files or controllers in multiple languages. Storing things is what a database is for and an additional call to get a list out is really not that big an impact on your performance.
Angular's $http object, which you are probably using to call your API has a caching option, which means you'll only need to retrieve the list once per app instantiation.
You could alternatively have a look at this post by Josh who found a way to pre populate a directive with JSON from the server before loading it.

dynamic ORM in node.js+mongodb

Is it possible to create a model where the relationships are dynamically generated by the application?
I saw the KeystoneJS project that does a nice job of defining the model (see: http://keystonejs.com/docs/database/#relationship-definitions)
But these need to be defined by node, I'm interested in creating these within the application. Are there any ORMs or framework projects that already do that? I I've seen frameworks like the MODxCMS that allow users to create additional fields, by putting everything from the custom (templatevar) values into one table. think mongodb would be great for setting this up without this single table approach.
Any idea how to go about setting this kind of system up? I'm not sure where to start.
I guess mongoose might help you here. And you may want to have a look at mongo-relation too.

yii objects and object fields

I'm not sure how to put this right.
I need to use yii to create an application which needs to use objects and fields.
Let's say that in my app I want to have those three objects: Computers, Servers, IPs. Each of these three objects will have it's own attributes:
Computer: CPU, Motherboard, Video adapter, IP (related to the object IP), Aquisition Date
Servers: Name, IP (related to object IP), etc...
IP: IP Address.
As you can see I also need a way to link my objects between them.
Every kind of attribute (object field) must be treated in it's own way, after it's own type. For example, we have a field called CPU which can be in a list of values. We have Aquisition Date and it must be treated like a date.
Well, the problem is that I need an extension to help me in creating those object types and setting their attributes. I don't know how to search for something appropriate.
Implementing this functionalities will take me a lot of time which I don't have right now. If there are no extensions, do you have any solution to implement one? I have some ideas for creating classes for every user field, classes which will implement an interface that render the methods properly for insert, update, etc.
Thank you!
You don't need any extension if you use Yii. You'd rather yake some time to read the tutorials. My advice is to begin with Larry Ullman's Learning Yii Series and then to go to the Definitive Guide
Once you have set your database and build your tables, you will only have to activate the Gii component of Yii framework and to use it's automated code generators to build your basic models, views and controllers.
The only thing you've left will be customization, of course. Yii + Gii save you all the repetitive work. But... read the docs.
[EDIT] after the OP comment below.
Is it an EAV model that you are looking for ? There is an unofficial Yii extension dealing with that : EAV Behavior. I have no idea whether it's good or not, as I definitely avoid to work with EAV databases. Let us know your opinion if you try to use it.

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