form for - rails form_for create new entry instead of updating -

i using form_for in order create new entry.

in controller set:

def create_ab_campaign   @campaign = campaign.find_by(id: params[:id],  account_id: current_account.id)   @campaign_id = params[:id] end 

in view do:

<%= form_for (@campaign), :url => {:controller => "campaigns", :action => "create_new_ab_campaign"} |f| %> <div class="form-group"> <%= f.label :name, "name", class: "control-label" %> <%= f.text_field :name, class: "form-control", placeholder: "name" %> </div> <%= f.submit "save settings" %> 

on submit want to create new entry instead of updating existing one.

i did following in controller:

def create_ab_campaign_new   @campaign_new = campaign.new(create_a_new_ab_campaign)    if @campaign_new.save     redirect_to(:controller =>"campaigns", :action =>"index")    else     redirect_to(:action =>"new")    end end  private   def create_a_new_ab_campaign     params.require(:campaign).permit(:name)   end 

i following: nomethoderror in campaignscontroller#update

it tries still use update instead of "create_a_new_ab_campaign"

i used update updating records - works fine.

def update   @campaign = campaign.find_by(id:params[:id], account_id: current_account.id)   @new = create_new_campaign   if @campaign.update_attributes(@new)     redirect_to(:controller =>"campaigns", :action =>"index")   else     render 'edit'   end end 

but described instead of update/edit want case , create new entry out of record.

thanks lot help!

update:

full error log:

nomethoderror in campaignscontroller#update undefined method `update_attributes' nil:nilclass

extracted source (around line #124): 122 123 124 125 126 127

@new = create_new_campaign @new[:page_type].delete_if{ |x| x.empty? } if @campaign.update_attributes(@new)   redirect_to(:controller =>"campaigns", :action =>"index") else   render 'edit' 

rails.root: /users/sschindler/demostore

application trace | framework trace | full trace app/controllers/campaigns_controller.rb:124:in `update'

update routes

routes:

post "campaigns/create_new_ab_campaign"

get "campaigns/create_new_ab_campaign"

post "/campaigns/:id/edit" => "campaigns#edit"

get "/campaigns/:id/edit" => "campaigns#edit"

post "/campaigns/create_ab_campaign" => "campaigns#create_ab_campaign"

get "/campaigns/create_ab_campaign" => "campaigns#create_ab_campaign"

post "/campaigns/:id" => "campaigns#edit"

post "/campaigns/:id" => "campaigns#new"

get "/campaigns/:id" => "campaigns#edit"

get 'campaigns/show'

get 'campaigns/index'

post '/campaigns/edit'

get '/campaigns/edit'

i'm assuming create_ab_campaign new route , create_ab_campaign_new post route. although little confused because have params[:id] value in #create_ab_campaign

from looks of though, form trying update because you're passing form_for created campaign variable: @campaign = campaign.find_by(...)

rails form_for check if object instance in db or if new model. if been created, patch update route; if new model (but not created) post create route.

in #new route, need assign @campaign campaign.new(account_id:current_account.id) instead of finding 1 thats been made.

update
based on comments, want duplicate model, change of fields , save new record. in case, you'd want send id of campaign model want copy form, can retrieve in create route, use model.dup, modify params, save.

def create_ab_campaign   @campaign = campaign.new   @campaign_id = params[:id] end 

add hidden field form

<%= form_for (@campaign), :url => {:controller => "campaigns", :action => "create_new_ab_campaign"} |f| %> <div class="form-group"> <%= hidden_field_tag :campaign_id, @campaign_id <%= f.label :name, "name", class: "control-label" %> <%= f.text_field :name, class: "form-control", placeholder: "name" %> </div> <%= f.submit "save settings" %> 

create route
dup campaign, make modifications, , check validity. sure not have uniqueness validations on model or youll run bit of trouble

def create_ab_campaign_new   @campaign_new = campaign.find(params[:campaign_id]).dup   @campaign_new.update(create_a_new_ab_campaign)    if @campaign_new.save     redirect_to(:controller =>"campaigns", :action =>"index")    else     redirect_to(:action =>"new")    end end