How do I create multiple submit buttons for the same form in Rails?

I need to have multiple submit buttons.

I have a form which creates an instance of Contact_Call.

One button creates it as normal.

The other button creates it but needs to have a different :attribute value from the default, and it also needs to set the attribute on a different, but related model used in the controller.

How do I do that? I can't change the route, so is there a way to send a different variable that gets picked up by [:params]?

And if I do then, what do I do in the controller, set up a case statement?

Solution 1:

You can create multiple submit buttons and provide a different value to each:

<% form_for(something) do |f| %>
    ..
    <%= f.submit 'A' %>
    <%= f.submit 'B' %>
    ..
<% end %>

This will output:

<input type="submit" value="A" id=".." name="commit" />
<input type="submit" value="B" id=".." name="commit" />

Inside your controller, the submitted button's value will be identified by the parameter commit. Check the value to do the required processing:

def <controller action>
    if params[:commit] == 'A'
        # A was pressed 
    elsif params[:commit] == 'B'
        # B was pressed
    end
end

However, remember that this tightly couples your view to the controller which may not be very desirable.

Solution 2:

There is also another approach, using the formaction attribute on the submit button:

<% form_for(something) do |f| %>
    ...
    <%= f.submit "Create" %>
    <%= f.submit "Special Action", formaction: special_action_path %>
<% end %>

The code stays clean, as the standard create button doesn't need any change, you only insert a routing path for the special button:

formaction:
The URI of a program that processes the information submitted by the input element, if it is a submit button or image. If specified, it overrides the action attribute of the element's form owner. Source: MDN

Solution 3:

You can alternatively recognized which button was pressed changing its attribute name.

<% form_for(something) do |f| %>
    ..
    <%= f.submit 'A', name: 'a_button' %>
    <%= f.submit 'B', name: 'b_button' %>
    ..
<% end %>

It's a little bit uncomfortable because you have to check for params keys presence instead of simply check params[:commit] value: you will receive params[:a_button] or params[:b_button] depending on which one was pressed.

Solution 4:

Similar solution to one suggested by @vss123 without using any gems:

resources :plan do
  post :save, constraints: lambda {|req| req.params.key?(:propose)}, action: :propose
  post :save, constraints: lambda {|req| req.params.key?(:finalize)}, action: :finalize
end

Notice that I avoid using value and use input name instead since submit button value is often internationalized / translated. Also, I'd avoid using this too much since it will quickly clutter your routes file.

Solution 5:

We solved using advanced constraints in rails.

The idea is to have the same path (and hence the same named route & action) but with constraints routing to different actions.

resources :plan do
  post :save, constraints: CommitParamRouting.new("Propose"), action: :propose
  post :save, constraints: CommitParamRouting.new("Finalize"), action: :finalize
end

CommitParamRouting is a simple class that has a method matches? which returns true if the commit param matches the given instance attr. value.

This available as a gem commit_param_matching.