Add custom fields to object in ROR application - ruby-on-rails

Question

I'm working on CRM platform.
I would like my users to add, edit and delete custom fields in Client, Contact and Lead objects. Those fields may be plain textfield, list, checkbox, tag etc. Those fields may be required or not. Those fields may have custom validation (that user will define).
Say one company from financials would like to add income to Client object, another would add order configuration to Lead object.
Is there any "enterprise-level" solution (ROR gem) for my problem.
Of cause I know about Custom configuration and config gem, but it doesn't look extensible enough.

Answer 1

Hard question, but this is how I would try to deal with it: I would make all the objects to be derived from a CustomField object, then I would create a one to many relationship between it and a Field model. Something like this:
create_table :field_types do |t|
t.string :name # This would identify the fields: checkbox, plain text, etc
end
create_table :fields do |t|
t.belongs_to :custom_field, null: false, index: true
t.belongs_to :field_type, null: false, index: true
t.string :name
end
class Field < ApplicationRecord
belongs_to :custom_field
belongs_to :field_type
end
class CustomField < ApplicationRecord
has_many :fields
end
This way you could just look into the specified fields on the database and mount it at the view.
Then I would create a table for each type of field that could be used by the users to save the data from the CustomField objects. For instance, I would check the Client field specifier, mount a view with checkboxes A and B. Then, I would get the data from the checkboxes and save each of them at the table Checkboxes with an identifier, so that I could tell that it came from clients.
Depending on what you need to do, another idea that pops to my head is to save the data as a JSON string into the database. This way you could have different fields with different values, all you would need to do is serialize and deserialize to save and load it from the database, respectively.
Sorry if it was a little confusing. Hope it helps.

Answer 2

Assuming your database is relational:
I would suggest to use Entity-Attribute-Value pattern:
https://en.wikipedia.org/wiki/Entity%E2%80%93attribute%E2%80%93value_model.
Here is a gem for it:
https://github.com/iostat/eav_hashes
Also document-oriented database like MongoDB would be an option, if you ever consider changing database. It is schemaless, so you can have different attributes for different instance.

Answer 3

I'm not aware of any out of the box options available, but you might be better off rolling your own on something like this anyway. It will allow you more flexibility, and shouldn't be terrible to implement. In terms of models, I'd probably go with a single-table inheritance table for the fields, probably using a jsonb column for customization options (assuming postgres):
create_table :fields do |t|
t.string :type, null: false # TextField, ListField, etc.
t.jsonb :config, default: {}, null: false
t.belongs_to :contact
end
You can then subclass as necessary for different use-cases:
class Field < ApplicationRecord
belongs_to :contact
end
class TextField < Field
def required=(required)
config[:required] = required
end
end
class CheckboxField < Field
def default_checked=(default_checked)
config[:default_checked] = default_checked
end
end
You can look into something like jsonb_accessor to make for a cleaner interface to the jsonb column.
Likewise, single-table inheritance looks like it may also make sense for the contacts as well, not sure what the base table should be, but maybe something like:
create_table :contacts do |t|
t.string :type, null: false # Contact, Lead, Client
end
class Contact < ApplicationRecord
end
class Lead < Contact
end

Answer 4

Here are some examples I found helpful for custom fields:
http://railscasts.com/episodes/403-dynamic-forms?view=asciicast
And:
https://github.com/lab2023/postgresql_jsonb_ransack_rails_5
https://gist.github.com/ismailakbudak/2ca1feac945999ec3e7d9cf0a373497a