How do I pass objects from one controller to another in rails? - ruby-on-rails

How do you pass an object built and submitted from one controller's show action to the create action of another controller while also retaining the instance variable of the former?
ItemsController:
def show
#item = Item.friendly.find(params[:id])
#trade = current_user.requested_trades.build
end
The form_for on my show page then makes a post request for #trade, with :wanted_item and :trade_requester as params.
TradesController:
def create
#item = ???
#trade = current_user.requested_trades.build
if #trade.save
format.html { redirect_to #item, notice: "success" }
else
format.html { redirect_to #item, notice "pick another number" }
end
etc...
end
Trade.rb:
belongs_to :trade_requester, class_name: "User"
belongs_to :trade_recipient, class_name: "User"
belongs_to :wanted_item, class_name: "Item"
belongs_to :collateral_item, class_name: "Item"
Routes.rb
resources :trades do
member do
post :accept
post :reject
end
end
Something about this feels wrong? Other questions on this subject seem to be about passing an object between different actions within the same controller - what I'm asking is not that.

First, I think I would make my routes more like:
resources :wanted_items do
resources :trades, shallow: true do
member do
post :accept
post :reject
end
end
end
Which would give you:
accept_trade POST /trades/:id/accept(.:format) trades#accept
reject_trade POST /trades/:id/reject(.:format) trades#reject
wanted_item_trades GET /wanted_items/:wanted_item_id/trades(.:format) trades#index
POST /wanted_items/:wanted_item_id/trades(.:format) trades#create
new_wanted_item_trade GET /wanted_items/:wanted_item_id/trades/new(.:format) trades#new
edit_trade GET /trades/:id/edit(.:format) trades#edit
trade GET /trades/:id(.:format) trades#show
PATCH /trades/:id(.:format) trades#update
PUT /trades/:id(.:format) trades#update
DELETE /trades/:id(.:format) trades#destroy
wanted_items GET /wanted_items(.:format) wanted_items#index
POST /wanted_items(.:format) wanted_items#create
new_wanted_item GET /wanted_items/new(.:format) wanted_items#new
edit_wanted_item GET /wanted_items/:id/edit(.:format) wanted_items#edit
wanted_item GET /wanted_items/:id(.:format) wanted_items#show
PATCH /wanted_items/:id(.:format) wanted_items#update
PUT /wanted_items/:id(.:format) wanted_items#update
DELETE /wanted_items/:id(.:format) wanted_items#destroy
Then in your form_for, I would do something like:
<% form_for wanted_item_trades_path(wanted_item: #wanted_item, trade: #trade) do |f| %>
...
<% end %>
That form_for syntax may not be exactly right, so you may need to futz with it.
This will generate a url something like:
/wanted_items/3/trades
Naturally, the '3' is just made up. It'll be whatever your #item.id is.
When you post the form, you should have a wanted_item_id in your params of 3. Then, in your TradesController, you'll do something like:
class TradesController < ApplicationController
def create
#wanted_item = Item.find_by(id: params[:wanted_item_id])
#trade = current_user.requested_trades.build(wanted_item: #wanted_item)
if #trade.save
format.html { redirect_to #item, notice: "success" }
else
format.html { redirect_to #item, notice "pick another number" }
end
end
...
end
BTW, it looks like you're using friendly_id. So, you could tweak all of the above to use a friendly_id instead of id. I don't use friendly_id, so you'll have to sort that on your own.

Related

How to implement retweet functionality in RoR?

I'm trying to implement retweet functionality on my app.
So I have my retweet_id in my tweets model
tweets schema
| user_id | content | created_at | updated_at | retweet_id
tweets.rb
belongs_to :user
has_many :retweets, class_name: 'Tweet', foreign_key: 'retweet_id'
user.rb
has_many :tweets
And in my tweets controller
tweets_controller.rb
...
def retweet
#retweet = Tweet.new(retweet_params)
if #retweet.save
redirect_to tweet_path, alert: 'Retweeted!'
else
redirect_to root_path, alert: 'Can not retweet'
end
end
Private
...
def retweet_params
params.require(:retweet).permit(:retweet_id, :content).merge(user_id: current_user.id)
end
In my view
tweets/show.html.erb
<%= link_to 'Retweet', retweet_tweet_path(#tweet.id), method: :post %>
My routes
resources :tweets do
resources :comments
resources :likes
member do
post :retweet
end
end
So when I try this I get an error
param is missing or the value is empty: retweet
So I remove .require from 'retweet_params' and that removes that error (though i'm unsure of how wise that is)
Then the link works but won't retweet - reverting to the fallback root_path specified in my action instead.
Unpermitted parameters: :_method, :authenticity_token, :id
Redirected to http://localhost:3000/
I'm not sure what i'm doing wrong. How can I get my retweets working? ty
The reason retweet_params raises an error is because your link link_to 'Retweet', retweet_tweet_path(#tweet.id), method: :post doesn't contain parameters like a new or edit form does. Instead you should create a new tweet that reference to tweet you want to retweet.
before_action :set_tweet, only: %i[show edit update destroy retweet]
def retweet
retweet = #tweet.retweets.build(user: current_user)
if retweet.save
redirect_to retweet, notice: 'Retweeted!'
else
redirect_to root_path, alert: 'Can not retweet'
end
end
private
def set_tweet
#tweet = Tweet.find(params[:id])
end
The above should automatically link the new tweet to the "parent". If this doesn't work for some reason you could manually set it by changing the above to:
retrweet = Tweet.new(retweet_id: #tweet.id, user: current_user)
The above approach doesn't save any content, since this is a retweet.
If you don't want to allow multiple retweets of the same tweet by the same user, make sure you have the appropriate constraints and validations set.
# migration
add_index :tweets, %i[user_id retweet_id], unique: true
# model
validates :retweet_id, uniqueness: { scope: :user_id }
How do we access the content of a retweet? The answer is we get the content form the parent or source (however you want to call it).
There is currently no association that lets you access the parent or source tweet. You currently already have:
has_many :retweets, class_name: 'Tweet', foreign_key: 'retweet_id'
To easily access the source content let's first add an additional association.
belongs_to :source_tweet, optional: true, inverse_of: :retweets, class_name: 'Tweet', foreign_key: 'retweet_id'
has_many :retweets, inverse_of: :source_tweet, class_name: 'Tweet', foreign_key: 'retweet_id'
With the above associations being set we can override the content getter and setter of the Tweet model.
def content
if source_tweet
source_tweet.content
else
super
end
end
def content=(content)
if source_tweet
raise 'retweets cannot have content'
else
super
end
end
# depending on preference the setter could also be written as validation
validates :content, absence: true, if: :source_tweet
Note that the above is not efficient when talking about query speed, but it's the easiest most clear solution. Solving parent/child queries is sufficiently difficult that it should get its own question, if speed becomes an issue.
If you are wondering why I set the inverse_of option. I would recommend you to check out the section Active Record Associations - 3.5 Bi-directional Associations.
Right now the error you're seeing is the one for strong params in Rails. If you can check your debugger or the HTTP post request that's being sent, you'd find that you don't have the params that you're "requiring" in retweet_params
def retweet_params
params.require(:retweet).permit(:retweet_id, :content).merge(user_id: current_user.id)
end
This is essentially saying that you expect a nested hash for the params like so
params = { retweet: { id: 1, content: 'Tweet' } }
This won't work since you're only sending the ID. How about something like this instead?
TweetsController.rb
class TweetsController < ApplicationController
def retweet
original_tweet = Tweet.find(params[:id])
#retweet = Tweet.new(
user_id: current_user.id,
content: original_tweet.content
)
if #retweet.save
redirect_to tweet_path, alert: 'Retweeted!'
else
redirect_to root_path, alert: 'Can not retweet'
end
end
end

Action Controller exception undefined method `merge' for xxx:String

I'm doing simple Reddit like site. I'm trying to add button to reporting posts. I create report model, using button_to i try to post data to report controller to create it but i received NoMethodError in ReportsController#create undefined method merge' for "post_id":String
model/report.rb
class Report < ApplicationRecord
belongs_to :reporting_user, class_name: 'Author'
has_one :post
end
report_controller.rb
class ReportsController < ApplicationController
def create
report = Report.new(report_params)
flash[:notice] = if report.save
'Raported'
else
report.errors.full_messages.join('. ')
end
end
def report_params
params.require(:post).merge(reporting_user: current_author.id)
end
end
and button in view
= button_to "Report", reports_path, method: :post, params: {post: post}
What cause that problem?
edit:
params
=> <ActionController::Parameters {"authenticity_token"=>"sX0DQfM0rp97q8i16LGZfXPoSJNx15Hk4mmP35uFVh52bzVa30ei/Bxk/Bm40gnFmd2NvFEqj+Wze8ted66kig==", "post"=>"1", "controller"=>"reports", "action"=>"create"} permitted: false>
To start with you want to use belongs_to and not has_one.
class Report < ApplicationRecord
belongs_to :reporting_user, class_name: 'Author'
belongs_to :post
end
This correctly places the post_id foreign key column on reports. Using has_one places the fk column on posts which won't work.
And a generally superior solution would be to make reports a nested resource:
# /config/routes.rb
resources :posts do
resources :reports, only: [:create]
end
# app/controller/reports_controller.rb
class ReportsController
before_action :set_post
# POST /posts/:post_id/reports
def create
#report = #post.reports.new(reporting_user: current_author)
if #report.save
flash[:notice] = 'Reported'
else
flash[:notice] = report.errors.full_messages.join('. ')
end
redirect_to #post
end
private
def set_post
#post = Post.find(params[:post_id])
end
end
This lets you simplify the button to just:
= button_to "Report", post_reports_path(post), method: :post
Since the post_id is part of the path we don't need to send any additional params.
If you do want to let the user pass additional info through a form in the future a better way to create/update resources with params and session data is by passing a block:
#report = #post.reports.new(report_params) do |r|
r.reporting_user = current_user
end
ActionController::Parameters#require returns the value of the required key in the params. Usually this would be an object passed back from a form. In this example require would return {name: "Francesco", age: 22, role: "admin"} and merge would work.
Your view is sending back parameters that Rails is formatting into {post: 'string'}. We would need to see your view code to determine what exactly needs to change.
Update: From the new code posted we can see that the parameter sent back is "post"=>"1". Normally we would be expecting post: {id: 1, ...}.
Update: The button in the view would need the params key updated to something ala params: {post: {id: post.id}} EDIT: I agree that params: {report: { post_id: post}} is a better format.
The problem seems to be in report_params. When you call params.require(:post), it fetches :post from params -> the result is string. And you are calling merge on this string.
I'd recommend change in view:
= button_to "Report", reports_path, method: :post, params: { report: { post_id: post} }
then in controller:
def report_params
params.require(:report).permit(:post_id).merge(reporting_user_id: current_author.id)
end
Note, that I changed also the naming according to conventions: model_id for id of the model, model or model itself.

Following Rails tutorial, undefined method 'create' for nil:NilClass, with nested resource

I'm following the Rails tutorial and making changes where appropriate, with the intention that my tutorial project will become a full-fledged production app after the completion of the tutorial.
I've run into a snag with the second model portion of the tutorial. Here is how I've written my second model.
In my policy.rb:
class Policy < ApplicationRecord
has_one :insured
end
In my insured.rb:
class Insured < ApplicationRecord
belongs_to :policy
end
In my routes.rb:
resources :policies do
resource :insured
end
In my insureds_controller.rb:
def create
#policy = Policy.find(params[:policy_id])
# next line is raising the error
#insured = #policy.insured.create(insured_params)
redirect_to #insured
end
private
def insured_params
params.permit(:name, :address, :phone, :email)
end
I've inspected the #policy object with render plain: #policy.inspect and can confirm that ActiveRecord is retrieving the policy correctly. When I inspect the attributes of #policy, using render plain: #policy.attribute_names.inspect, I don't see an insured attribute, which I thought Rails was supposed to automatically manage for me. In the tutorial, an article has_many :comments, and a comment is supposedly easily created and associated with the parent article with this call: #article.comments.create(comment_params). I also noticed that the tutorial uses params.require(:comment).permit(...) while I have to use params.permit(...), after inspecting the params hash I saw that the :insured attributes existed in the top-level of the hash, instead of being tied to an :insured key within the hash.
I tried manually saving and assigning the #insured object like so:
def create
#policy = Policy.find(params[:policy_id])
#insured = Insured.new(insured_params)
if #insured.save
#policy.insured = #insured
redirect_to #insured
end
end
Only to run into the following error in my .../insureds/new.html.erb:
<h1>New Insured</h1>
<h1><%= #policy.policy_number %></h2>
<%= render 'form' %>
<%= link_to 'Cancel', policy_path(#policy) %>
Which derives from my partial form .../insureds/_form.html.erb:
# the following line raises the error
<%= form_with model: #insured, local: true do |form| %>
# html omitted for brevity
<% end %>
Error: 'undefined method insureds_path'. This is weird because when I inspect the HTML I can see the form action for this view is /policies/[:id]/insured.
Sorry for the massive wall of text, I wanted to show you guys that I did try to figure out what is going wrong.
There is an error in your config/routes.rb file:
resources :policies do
# change it for:
collection do
get 'insured', to: 'policies#show_insured', as: 'show_policy_insured'
# maybe unnecessary to be here
# get 'insured/new', to: 'insureds#new', as: 'new_policy_insured'
# post 'insured/create', to: 'insureds#create', as: 'create_policy_insured'
# delete 'insured/delete', to: 'insureds#delete', as: 'delete_policy_insured'
end
end
# add resources here
resources :insureds
In policy_controller.rb:
def show_insured # 'policy/:id/insureds/
end
In insureds_controller.rb:
def show # '/insureds/:id'
end
def create
...
redirect_to show_policy_insured && return if #insured_policy
end
# before_filter or before_action
#policy = Policy.find(params[:id])
#insured_policy = #policy.insured
Check it and run this to see your routes:
$ bundle exec rake routes
get /policies/:id/insured => 'policies_controller#show_insured'
get /insureds/:id => 'insureds_controller#show'
get /insured/new => 'insureds_controller#new'
post /insureds/create => 'insureds_controller#create'
delete /insureds/:id/delete => 'insureds_controller#delete'
#maguri, that's not all necessary. The stumbling block I was running into was that Rails couldn't automatically determine the correct routes. When I provided my own urls in the form_with declarations, everything went smoothly.
Observe the following change in my _form.html.erb for the Insured model, which belongs_to Policy, which has_one Insured.
<%= form_with model: #insured, url: policy_insured_path(#policy) local: true do |form| %>
In my updated insureds_controller.rb file, using #Phlip's suggestion:
def create
#policy = Policy.find(params[:policy_id])
#insured = #policy.create_insured(insured_params)
if #policy.insured.save
redirect_to policy_insured_path(params[:policy_id])
else
render 'new'
end
end
This allows me to keep routes.rb clean and simple:
resources :policies do
resource: insured
end
Thank you for your answer, it helped me discover the problem was with my routes.

Ruby on Rails - Pass ID from another controller

I have two models. First is Taxirecord and second is Carpark. Each Taxirecord may have its own Carpark. I have a problem with passing taxirecord_id to Carpark record. I have route
car_new GET /taxidetail/:taxirecord_id/carpark/new(.:format) carparks#new
And i want to pass :taxirecord_id, which is id of taxirecord that im editing, to my create controller.
My carpark model:
class Carpark < ActiveRecord::Base
belongs_to :taxirecord
end
In controller im finding taxirecord_id by find function based on param :taxirecord_id, but id is nil when create is called. Can you please help me to find out what Im doing wrong and how Can I solve this problem? Thanks for any help!
My carpark controller
class CarparksController < ApplicationController
def new
#car = Carpark.new
end
def create
#car = Carpark.new(carpark_params, taxirecord_id: Taxirecord.find(params[:taxirecord_id]))
if #car.save
flash[:notice] = "Zaznam byl ulozen"
redirect_to root_path
else
flash[:notice] = "Zaznam nebyl ulozen"
render 'new'
end
end
private def carpark_params
params.require(:carpark).permit(:car_brand, :car_type, :driver_name, :driver_tel)
end
end
I finally get it work
Ive added <%=link_to 'New Carpark', {:controller => "carparks", :action => "new", :taxirecord_id => #taxi_record.id }%>
to my taxirecord form and to carpark form <%= hidden_field_tag :taxirecord_id, params[:taxirecord_id] %>
And to my carpark controller : #carpark.taxirecord_id = params[:taxirecord_id]
Thanks everyone for great support and help!
I'd lean towards using something like:
before_action :assign_taxirecord
...
private
def assign_taxirecord
#taxirecord = TaxiRecord.find(params[:taxirecord_id])
end
And then in the create action:
def create
#car = #taxirecord.build_carpark(carpark_params)
...
end
Obviously there's a little tailoring needed to your requirements (i.e. for what actions the before_action is called), but I hope that helps!
No need to send taxirecord id.
class Carpark < ApplicationRecord
belongs_to :taxirecord
end
class Taxirecord < ApplicationRecord
has_one :carpark
end
Rails.application.routes.draw do
resources :taxirecords do
resources :carparks
end
end
for new taxirecord
t = Taxirecord.new(:registration => "efgh", :description =>"test")
for new carpark
t.create_carpark(:description=>"abcd")
#=> #<Carpark id: 2, taxirecord_id: 2, description: "abcd", created_at: "2017-10-12 10:55:38", updated_at: "2017-10-12 10:55:38">

Routing Error: No route matches [POST] "/flex_quiz/new"

In my rails app I'm trying to use a form partial to display the same quiz on the new and edit views. I can see the new view page, but when I hit <%= f.submit "Submit Answers" %> I get an error saying No route matches [POST] "/flex_quiz/new".
Here is the form for line in my partial:
<%= form_for #flex_quiz, url: url do |f| %>
And here's how the locals stand in my new view:
<%= render partial: "quiz", locals: { url: new_flex_quiz_path, method: :post } %>
And my edit view:
<%= render "quiz", url: edit_flex_quiz_path(#flex_quiz), method: :put %>
Here are the route paths:
Prefix Verb URI Pattern Controller#Action
...
flex_quiz_index GET /flex_quiz(.:format) flex_quiz#index
POST /flex_quiz(.:format) flex_quiz#create
new_flex_quiz GET /flex_quiz/new(.:format) flex_quiz#new
edit_flex_quiz GET /flex_quiz/:id/edit(.:format) flex_quiz#edit
flex_quiz GET /flex_quiz/:id(.:format) flex_quiz#show
PATCH /flex_quiz/:id(.:format) flex_quiz#update
PUT /flex_quiz/:id(.:format) flex_quiz#update
DELETE /flex_quiz/:id(.:format) flex_quiz#destroy
Can anyone suggest how to fix this? I have looked at several similar posts (like this and this) but since I'm using partials the solution here is going to have to be a bit different.
EDIT
Here are my definitions in my flex_quiz_controller:
class FlexQuizController < ApplicationController
before_action :require_sign_in
def show
#flex_quiz = FlexQuiz.find(params[:id])
end
def new
#flex_quiz = current_user.build_flex_quiz
end
def create
#flex_quiz = FlexQuiz.new
#flex_quiz.flex01 = params[:flex_quiz][:flex01]
#flex_quiz.flex02 = params[:flex_quiz][:flex02]
#flex_quiz.flex03 = params[:flex_quiz][:flex03]
#flex_quiz.flex04 = params[:flex_quiz][:flex04]
#flex_quiz.flex05 = params[:flex_quiz][:flex05]
#flex_quiz.flex06 = params[:flex_quiz][:flex06]
#flex_quiz.flex07 = params[:flex_quiz][:flex07]
#flex_quiz.flex08 = params[:flex_quiz][:flex08]
#flex_quiz.flex09 = params[:flex_quiz][:flex09]
#flex_quiz.flex10 = params[:flex_quiz][:flex10]
#flex_quiz.user = current_user
if #flex_quiz.save
flash[:notice] = "Quiz results saved successfully."
redirect_to user_path(current_user)
else
flash[:alert] = "Sorry, your quiz results failed to save."
redirect_to welcome_index_path
end
end
def edit
#flex_quiz = FlexQuiz.find(params[:id])
end
def update
#flex_quiz = FlexQuiz.find(params[:id])
#flex_quiz.assign_attributes(flex_quiz_params)
if #flex_quiz.save
flash[:notice] = "Post was updated successfully."
redirect_to user_path(current_user)
else
flash.now[:alert] = "There was an error saving the post. Please try again."
redirect_to welcome_index_path
end
end
private
def flex_quiz_params
params.require(:flex_quiz).permit(:flex01, :flex02, :flex03, :flex04, :flex05, :flex06, :flex07, :flex08, :flex09, :flex10)
end
end
If you want to create new flex_quiz objects, then you're going to want to POST to flex_quiz_index_path.
Notice in your route paths, if you look at new_flex_quiz, the HTTP verb is a GET.
It may be slightly unintuitive, but the new action is actually a GET request.
The action in which the object is supposed to be created in is the create action.
So to solve your problem this should do the trick:
<%= render partial: "quiz", locals: { url: flex_quiz_index_path, method: :post } %>
EDIT:
Instead of defining locals, you can simply define your forms in form_for as such:
You will also have to define #flex_quiz in your controller actions as well (in your case new and edit) form_for will automatically infer the appropriate URL.
From documentation:
However, further simplification is possible if the record passed to
form_for is a resource, i.e. it corresponds to a set of RESTful
routes, e.g. defined using the resources method in config/routes.rb.
In this case Rails will simply infer the appropriate URL from the
record itself.
You'll also need to change the naming from singular form to plural.
The rails to do resuable forms is:
app/views/flex_quiz/_form.html.erb:
<%= form_for(#flex_quiz) do |f| %>
# ...
<% end %>
app/views/flex_quiz/new.erb:
<h1>Create a new quiz</h1>
<%= render 'form' %>
app/views/flex_quiz/edit.erb:
<h1>Edit a quiz</h1>
<%= render 'form' %>
While using locals can often be a good idea its not needed here. Note we just pass the resource and not a URL to form_for - that is convention over configuration in action and is what makes Rails awesome.
Rails figures out all by itself what URL to use for the action attribute and what method to use based on if the resource has been saved.
However for this to work you to actually follow the conventions. Make sure you are using the proper plural forms (the plural of quiz is quizzes):
resources :flex_quizzes
class FlexQuizzesController < ApplicationController
end
Unfortunately when it comes to rest of your setup you need to revisit the drawing board. Its not very realistic to think that you can do this with a single model. You would usually have several models with relations:
class Quiz
has_many :questions
end
class Question
belongs_to :quiz
has_many :answers
end
class Answer
belongs_to :question
end
class UserQuiz
belongs_to :user
belongs_to :quiz
end
class UserAnswer
belongs_to :question
belongs_to :answer
end
You would use one or several controllers to let admins create the quizes and a separate controller to let users answer the quiz. Its a quite common domain so you should be able to find plenty of examples.

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