Using non associated models data in a form - ruby-on-rails

Is it possible to access another models attributes without having associations? For example I want to create a Prediciton record via a form using the fixture models attributes
<%= form_for #prediction do |f| %>
<%= f.fields_for :fixtures, #fixtures do |builder| %>
<%= builder.text_field :home_team %> VS <%= builder.text_field :away_team %><%= f.text_field :home_score %><%= f.text_field :away_score %><br>
<% end %>
<% end %>
how would i get the attributes of the fixture model without associating the two models?
Thanks

It's much easier if you create the association. If you are not going to create the association, such in the case where you are using a view not backed by a model and your are pulling in and modifying various models from it (assumption I am making) you can do something similar to this:
First make sure you setup routes.rb for whichever methods you are planning to use against the various models.
predictions model
#fixtures = Fixture.all
or specific attributes example
#fixtures = Fixture.select([:home_team, :away_team, :home_score, :away_score]).all
The above is if you are updating another models records. You will also need to modify the create method.
Your view you would want to change from a form_for to a form_tag:
form_tag('/predictions') do
Hopefully this gets you going in the right direction.

Related

Complex Rails Form Best Practices

I've got a relatively complex form I'm trying to code efficiently. Most online examples of nested forms deal with very clear hierarchical relationships, mine does not.
Below is the data model. The essential job of the form is to create a "Job Entry" record while at the same time creating a new "Entity" record - which is a person. Several relationships come to bear in this form.
A "Job" is already created. The Job has 1-to-many "Questions" which exist before the user hits this form. However, they must fill in "Answers" to the questions. They also choose one of many pre-created "Job Roles".
The question is how to leverage "form_with" and "fields_for" for all these inter-related models.
My assumption is to ditch built-in helpers and just use a form_tag and roll everything together manually. But maybe there is a "correct" way to roll forms that do not necessarily abide by parent-child relationships? In my example, there is no pure top-level object to start with since many child objects already have records, but maybe I am wrong and Entity should be the starting point?
Entity has_many Job_Roles
Entity has_many Job_Entries
Job has many Job_Roles
Job has_many Job_Entries
Job has_many Questions
Question has many Answers
Answers belong_to Entity
Agency has_many Job_Entries
etc...
There is no need to ditch the built-in helper: Rails has thought about that, it's called nested forms.
Here is an example:
<%= form_with model: #job do |f| %>
Job entries:
<ul>
<%= f.fields_for :job_entries do |je_form| %>
<li>
<%= je_form.label :kind %>
<%= je_form.text_field :kind %>
<%= je_form.label :street %>
<%= je_form.text_field :street %>
...
</li>
<% end %>
</ul>
<% end %>
You can nest as many children forms as you'd like using fields_for. Don't forget to use accepts_nested_attributes_for in the parent models.
Nested forms as Mike proposed are a rails-way solution of your problem. It is ok - but for complex forms, with lot of validations, it may not be the best solution). You could consider using a FormObject pattern instead.
FormObject is a simple ruby class that uou can keep it i.e. in Forms folder and use as below:
class JobEntryForm
include ActiveModel::Model
attr_accessor :customer_id, :agency_id, :name, :question_text #you can use atributes from different models
validates :customer_id, presence: true #you can validate yu attributes as you want - your in necessity to use model validation
def initialize(attributes:)
#customer_id = attributes[:customer_id]
#agency_id = attributes[:agency_id]
#name = attributes[:name]
#question_text = attributes[:question_text]
end
#implement whatever you need
end
than in you controller:
#form = JobEntryForm.new
and you your view:
<%= form_for #form do |f| %>
<%= f.label :customer_id, 'Customer' %>:
<%= f.text_field :customer_id %>
...
<%= f.submit %>
<% end %>
And - at the end - in your controller create method:
def create
#form = CreateJobEntry.new.call(attributes: form_params) #service object to keep your controller clean.
end

Accessing different model elements in Rails

I am inexperienced in Rails (version 4.2.5) and struggle with how views access database elements. I have worked through a number of different tutorials but still don't really understand why it doesn't work the way I think it does!
I have models that have been set up with references which I believe that establishes foreign keys in the database. I want to edit entries in the database that belong in a different model.
So, a Wines is a model that references Winemakers.
class Wine < ActiveRecord::Base
belongs_to :winemaker
end
In my _edit_form.html.erb file I have the following code which works but does not give me what I want:
<%= simple_form_for(#wine) do |f| %>
<div class="field">
<%= f.label :winemaker_id %>
<%= f.text_field :winemaker_id %>
</div>
This produces a simple box and in the box the integer that is winemaker_id is displayed but what I want is the actual name of the winemaker. I have tried :winemaker_id.name, #winemaker.name and many variations on those theme but I clearly do not understand how this works. I have tried reading various documentation but I am none the wiser.
Can someone please explain in simple terms how accessing different models works?
If your Winemaker model has been defined as follows:
class Winemaker < ActiveRecord::Base
has_many :wines
end
That means you can write the followings:
#winemaker.wines - returns all the wines belongs to a winemaker
#wine.winemaker - returns the winemaker to whom the wine belongs
If you want to show and edit the Winemaker name from Wine form, then you can do it using accepts_nested_attributes_for
Just modify your Wine model as follows:
class Wine < ActiveRecord::Base
belongs_to :winemaker
accepts_nested_attributes_for :winemaker
end
Now you can make a small change to your form as follows:
<%= form_for #wine do |f| %>
<%= f.fields_for :winemaker do |w|%>
<%= w.text_field :name%>
<% end %>
<%= f.submit%>
<% end %>
Try the following code:
<%= simple_form_for(#wine) do |f| %>
<div class="field">
<%= f.label :winemaker_id %>
<%= f.collection_select(:winemaker_id, Winemaker.all, :id, :name) %>
</div>
Have a look at http://apidock.com/rails/ActionView/Helpers/FormOptionsHelper/collection_select for more information.

Form Design: How to best display/add different statuses?

I am working on a rails form. Essentially, a person can have multiple statuses and switch between the different statuses. In database table, the display will be simple as follows:
status start_date end_date
work 1/1/15 1/10/15
sick 1/11/15 2/15/15
work 2/16/15 3/15/15
sick 1/15/15 1/14/15
I need to prompt user to input these information. I have made a status class which belongs to a person class. So basically, these fields will be a part of nested forms.
My question is: How can I dynamically display these information to make forms elegant and clean to use?
Thanks!
If I understood your domain, your Person has many Status, right?
The simplest way to do it is use the gem cocoon. Your view will look like this:
<%= form_for #person do |person_form| %>
<%= person_form.input :name %>
<%= person_form.fields_for :statuses do |status_form| %>
<%= status_form.field :start_date, :end_date %>
<!-- cocoon's method to dynamically add nested forms -->
<%= link_to_add_association 'add status', person_form, :statuses
<% end %>
<% end %>

Rails form for mailing

I'm trying to build a form which preloads content from two models (two variables being passed, being shown in the textfields) and then, not saves the data but sends the altered content (from the textfields) as two(?) variables to a mailer class.
I've managed to preload the data from one of the two models but am not sure how the form_for tag has to look like to get both models loaded as well as targeting the mailer class method instead of updating the model entity when pressing "send".
Do I need the accepts_nested_attributes_for attribute inside the model if I'm not saving anything?
I hope someone could give me an small example of the crucial parts. A thousand thanks!
You can use fields_for to include other models in same form. You can use it inside the same form_for what is present.
Checkout the example here from the api docs,
<%= form_for #person do |person_form| %>
First name: <%= person_form.text_field :first_name %>
Last name : <%= person_form.text_field :last_name %>
<%= fields_for #person.permission do |permission_fields| %>
Admin? : <%= permission_fields.check_box :admin %>
<% end %>
<%= f.submit %>
<% end %>
when you submit the data from this form, you can just use that data to pass to the mailer class from controller. UserMailer.get_user_info(params[:name], params[:address]).send
Creates a scope around a specific model object like #form_for, but doesn't create the form tags themselves. This makes #fields_for suitable for specifying additional model objects in the same form.
Refer Docs here:.
fields_for(record_name, record_object = nil, options = {}, &block)

how to handle multiple models in a rails form

http://weblog.rubyonrails.org/2009/1/26/nested-model-forms
This post helped in learning how to handle multiple models in a rails form. It works as long as the models are nested. what if they are not? lets say, I have a form, where the user fills personal details, address details and a bunch of checkboxes specifying her interests. There are at least 3 tables involved in this one single form, what is the best way to handle this, without having 3 different save buttons?
Two options:
First is ActivePresenter which works well for this.
Second is just to use fields_for:
<%= form_for #user do |f| %>
<%=f.label :name %>
<%=f.text_field :name %>
<%= fields_for #address do |fa| %>
<%=fa.label :city %>
<%=fa.text_field :city %>
<% end %>
<% end %>
Then in the controller, save the records.
#user = User.new(params[:user])
#address = Address.new(params[:address])
ActivePresenter works so well though.
Also found a railsforum post via Google, which would work well.
You can refer this tutorial by The Pragmatic Programmers
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