I have a database of objects (tools) in my Ruby on Rails project. When I use "rails dbconsole" and
select * from tools;
it returns a whole list of tool objects. But when I try to view the following page, it gives me an error.
Page:
<!DOCTYPE html>
<html lang="en">
<%= stylesheet_link_tag "tools", :media => "all" %>
<body>
<%= #tools.each do |tool| %>
<%= link_to(tool(image_tag.image_url)) %>
<% end %>
</body>
</html>
Error:
undefined method `each' for nil:NilClass
When I change the code to add an if statement against nil objects, the page works (without displaying any tools).
<% if #tools.nil? %>
<% else %>
<%= #tools.each do |tool| %>
<%= link_to(tool(image_tag.image_url)) %>
<% end %>
<% end %>
So it seems like #tools doesn't have any values in it, but when I look at it in the dbconsole, there are tools there. I can't figure this out, and I've spent the past few days googling for answers, so any and all ideas would be welcome!
EDIT: Added tools_controller.rb
class ToolsController < ApplicationController
before_filter :check_authentication
def check_authentication
unless session[:user_id]
session[:intended_action] = action_name
session[:intended_controller] = controller_name
redirect_to new_session_url
end
end
def new
#tool = Tool.new
respond_to do |format|
format.html # new.html.erb
format.json { render :json => #tool }
end
end
def show
end
def index
#tools = Tool.all
end
# GET /tools/1/edit
def edit
#tool = Tool.find(params[:id])
end
# POST /tools
# POST /tools.json
def create
#tool = Tool.new(params[:tool])
respond_to do |format|
if #tool.save
format.html { redirect_to #tool, :notice => 'tool was successfully created.' }
format.json { render :json => #tool, :status => :created, :location => #tool }
else
format.html { render :action => "new" }
format.json { render :json => #tool.errors, :status => :unprocessable_entity }
end
end
end
end
Loading #tools in a before_filter for every action as #nbarraille has suggested is a bad idea, because there are many (probably most) actions where you will definitely not need the full set of tools (e.g. create and destroy). The line #tools = Tool.all hits your database so you should minimize the number of times you use it.
For the case you have here, you only need to change your show action to get this to work:
def show
#tools = Tool.all
end
However, note that normally the show action is for displaying a single resource (tool), not the whole list of resources (which is normally done in the index action). It looks like you're deviating from the normal way of doing things, is there any particular reason why?
In order for the #tools variable to be accessible from your view, you need to declare it in your controller, like this:
#tools = Tool.all
If you want it to be only accessible from one page, just declare it in the according method.
Here is an example, assuming you want to make the variable available for your home/index page:
class HomeController < ApplicationController
def index
#tools = Tool.all
respond_to do |format|
format.html # index.html.erb
end
end
end
If you want it to be accessible in all your pages, you can declare it in the before_filter method of your ApplicationController.
Here is how to do this:
class ApplicationController < ActionController::Base
protect_from_forgery
before_filter :load_variables
# Load variables to be used everywhere
def load_variables
#tools = Tool.all
end
end
Related
I cannot seem to find the problem. In my venues show template, I want to show the venue name, and under that, I list all the venues in the database
<%= venu.name %>
<% #venus.each do |v| %>
I get the error that #venus is nil... but it is defined in my controller:
undefined method 'each' for nil:NilClass
venues_controller.rb
class VenuesController < ApplicationController
before_action :find_venue, only: [:show, :edit, :update, :destroy]
def index
#venus = Venue.all
end
def show
render :layout => nil
#venus = Venue.all
end
def new
#venu = Venue.new
end
def create
#venu = Venue.new(venue_params)
#venu.save
end
def edit
end
def update
end
def destroy
end
private
def venue_params
params.require(:venue).permit(:name, :phone, :address, :description, :type)
end
def find_venue
#venu = Venue.find(params[:id])
end
end
I have a resources :venues route in my routes.rb.
I am not sure what is causing this problem.
In your show method, you should render at the end
def show
#venus = Venue.all
render :layout => nil
end
Remove render :layout => nil from your show action.
And in your view, you need to use the instance variable #venu instead of venu
<%= #venu.name %>
I wonder why you use two instance variables for action show
#venu (via find_venue before_filter) & #venus via the action itself.
Best practice would be removing this line from action show, since show action normally used to show details for one element from a list.
#venus = Venue.all
and use #venu set by the before_filter instead.
But if you do want to keep both then re-order the lines in show action
#venus = Venue.all
render :layout => nil
Also, change the venu to #venu in the show.html.erb and if you like correct the typo in the instance variables #venu => #venue :) (Could happen to any of us)
Usually in the index method, it should show all the venus, and in the show method it would show detailed view of each venue.
Try setting something like this:
def index
#venus = Venue.all
end
def show
render :layout => nil
#venue = Venue.find(params[:id])
end
now in show.html.erb you should be able to use
#venue.name
and in your index.html.erb, you can iterate over the venus like so:
<% #venus.each do |v| %>
<%= link_to v do %>
<%= v.name %>
<% end %>
<% end %>
The above answer is correct. You can use #venus = Venue.all in your show view but because you render first it throws you an error. Just render at the end.
I have researched similar questions however I don't feel link they have addressed my particular issue:
Rails form_for results in POST instead of PUT when trying to edit
form_for with nested resources
I'm a novice with Rails (using Rails 4.2.5) an am attempting my first application. My issue is two fold: (1) When a user goes to edit a user story the fields of the form do not populate with previously inputted data (2) When the form is resubmitted, a new entry is created, opposed to editing the old data.
I have a feeling that my form_for for user_stories/edit.html.erb is the issue. When I take out the .build method from the form I get the following error message:
undefined method `to_key' for #UserStory::ActiveRecord_Associations_CollectionProxy:0x007f456a759138>
The projects/_form.html.erb for my project's view does not have the .build method and functions correctly. However the only way I can get the `user_stories/_form.html.erb form to work is if I attach the build method.
Here is my code:
user_story.rb
class UserStory < ActiveRecord::Base
belongs_to :project
belongs_to :user
include RankedModel
ranks :row_order
end
project.rb
class Project < ActiveRecord::Base
has_many :user_stories
belongs_to :user
end
routes.rb
Rails.application.routes.draw do
devise_for :users
resources :projects do
resources :user_stories
end
end
resources :user_stories do
post :update_row_order, on: :collection
end
root 'welcome#index'
end
user_stories/_form.html.erb
<%= form_for([#project, #user_story.build]) do |f| %>
<div class="form-group">
<p>As a ...</p>
<%= f.text_field :param1, placeholder: "type of user", class: "form-control" %>
</div>
<div class="form-group">
<p>I want ...</p>
<%= f.text_field :param2, placeholder: "desired functionality", class: "form-control" %>
</div>
<div class="form-group">
<p>so that...</p>
<%= f.text_field :param3, placeholder: "reason for desired functionality", class: "form-control" %>
</div>
<div class="actions">
<%= f.submit class: "btn btn-primary" %>
</div>
<% end %>
user_stories_controller.rb
class UserStoriesController < ApplicationController
before_action :set_project
before_action :set_user_story, except: [:create]
def index
#user_story = #project.user_stories.rank(:row_order).all
end
def update_row_order
#user_story.row_order_position = user_story_params[:row_order_position]
#user_story.save
render nothing:true # this is a POST action, updates sent via AJAX, no view rendered
end
def create
#user_story = #project.user_stories.create(user_story_params)
redirect_to #project
end
def new
end
def destroy
if #user_story.destroy
flash[:success] = "User story deleted"
else
flash[:error] = "User story could not be deletd"
end
redirect_to #project
end
def complete
user_story.update_attribute(completed_at, Time.now)
redirect_to #project, notice: "User story completed functionality complete"
end
def update
respond_to do |format|
if #project.user_stories.update(#project, user_story_params)
format.html { redirect_to project_path(#project), notice: 'User story was successfully updated.' }
format.json { render :show, status: :ok, location: #user_story }
else
format.html { render :edit }
format.json { render json: #user_story.errors, status: :unprocessable_entity }
end
end
end
def edit
#project = Project.find(params[:project_id])
#user_story = #project.user_stories(params[:id])
end
def show
end
private
def set_project
#project = Project.find(params[:project_id])
end
def set_user_story
#user_story = #project.user_stories(params[:id])
end
def user_story_params
params[:user_story].permit(:param1, :param2, :param3, :row_order_position)
end
end
There are just a few changes needed (tweaks, really), and I'll go through them top-to-bottom.
1) before_action :set_user_story
This will use the param[:id] to find the proper #user_story model object and automatically make it available to the proper methods. In this case it's being excepted for :create, but should also exclude other methods that don't have an :id in the route. Use this instead:
before_action :set_user_story, except: [:index, :new, :create]
This will solve (or prevent) some annoying and persistent ActiveRecord failures.
2) The index action
In this method, the name of the variable is non-standard by Rails naming conventions. The variable is currently singular, but represents a list of UserAction model object, which typically uses a plural name. Use this, instead:
def index
#user_stories = #project.user_stories.rank(:row_order).all
end
This change will cause a break in the app/views/user_stories/index.html.erb view, where any use of the #user_story variable would need to be changed to #user_stories. Keeping with naming conventions has many immediate and long-term benefits, so it's worth making the extra effort to change this to be consistent.
Note: the index action typically doesn't have a singular model object to work with, as this action is used to provide a list of the model objects.
3) The new action
The new action is used to create and initialize a new model object for editing. As the before_action :set_user_story is no longer being called for the new action, the #user_story model object has to be created here. This code will do that correctly:
def new
#user_story = UserStory.new
#user_story.project = #project
# Set other important default values for display now
end
And at this point, you should be able to successfully create a new UserStory model object, ready to be edited by the user.
4) The edit action
As the before_action :set_user_story handler is already being called for the edit action, there's no need to query for #user_story from within the body of the edit action; that line can be removed:
def edit
#project = Project.find(params[:project_id])
end
This will actually fix the original issue that was reported, as this form of find will (unfortunately for this situation) return multiple records, which means that you get a collection back, and not a single record. This is the actual cause of this error message:
undefined method `to_key' for #UserStory::ActiveRecord_Associations_CollectionProxy:0x007f456a759138>
Assigning the #user_story within the edit action overwrote the value that had previously been assigned from the before_action handler, and replaced it with an improper query result.
5) The complete action
The complete action is a custom member action, which means that it depends on the :id, just like many of the other actions. The code is almost correct, except that the user_story variable used within the body of the method is actually missing the #; this is originally retrieved by the before_action handler.
def complete
#user_story.update_attribute(completed_at, Time.now)
redirect_to #project, notice: "User story completed functionality complete"
end
It's likely that this method had not been called yet during testing, as the edit action was an upstream test that failed. This should work when you get to testing this method.
6) Teh codez
Changing those few details will finalize the UserStoriesController, which was in pretty great shape to begin with. Adding in those changes, this is the final controller code:
class UserStoriesController < ApplicationController
before_action :set_project
before_action :set_user_story, except: [:index, :new, :create]
def index
#user_stories = #project.user_stories.rank(:row_order).all
end
def update_row_order
#user_story.row_order_position = user_story_params[:row_order_position]
#user_story.save
render nothing:true # this is a POST action, updates sent via AJAX, no view rendered
end
def create
#user_story = #project.user_stories.create(user_story_params)
redirect_to #project
end
def new
#user_story = UserStory.new
#user_story.project = #project
# Set other important default values for display now
end
def destroy
if #user_story.destroy
flash[:success] = "User story deleted"
else
flash[:error] = "User story could not be deleted"
end
redirect_to #project
end
def complete
#user_story.update_attribute(completed_at, Time.now)
redirect_to #project, notice: "User story completed functionality complete"
end
def update
respond_to do |format|
if #project.user_stories.update(#project, user_story_params)
format.html { redirect_to project_path(#project), notice: 'User story was successfully updated.' }
format.json { render :show, status: :ok, location: #user_story }
else
format.html { render :edit }
format.json { render json: #user_story.errors, status: :unprocessable_entity }
end
end
end
def edit
#project = Project.find(params[:project_id])
end
def show
end
private
def set_project
#project = Project.find(params[:project_id])
end
def set_user_story
#user_story = #project.user_stories(params[:id])
end
def user_story_params
params[:user_story].permit(:param1, :param2, :param3, :row_order_position)
end
end
We have an error in our erb files and the screen shot is here
We have everything in games.html.erb as below
<h1>Games#game</h1>
<%= form_for(#game) do |f| %>
<div class="game-field">
<%= f.label :name %>
<%= f.text_field :name %>
</div>
<div class="actions">
<%= submit_tag "Game Created", :class=> "btn" %>
</div>
<% end %>
and here is the controller
class GamesController < ApplicationController
before_filter :store_location, :only => [:index, :show]
before_filter :require_user, :only => :show
before_filter :assign_game, :only => [:show, :destroy]
def index
#game = Game.new
end
def new
#game = Game.new
end
#game.add_player_from_user(current_user)
respond_to do |format|
format.html
format.json do render :json => {
:shouldStartNewRound => #game.is_ready_for_new_round?,
:shouldPassCards => #game.is_ready_to_pass?,
:isStartingFirstRound => #game.rounds.empty?,
:shouldReloadWaitAutoPlay => #game.should_reload?(current_player),
:shouldReloadAndJustWait => #game.should_reload_and_wait?(current_player)
}
end
end
end
def create
#game = Game.new(params[:game])
api_key = ""
api_secret = ""
#openTok = OpenTok::OpenTokSDK.new api_key, api_secret
session = #openTok.create_session request.remote_addr
#game.update_attributes(:session_id => session.session_id)
name = game[:name] # input from html
#game[:name] = name # setting input into db object (model)
if #game.save
redirect_to #game, alert: "game created"
else
render action: 'new'
end
end
def destory
#game.destory
redirect_to games_url
end
def reload
reload_partial
end
end
We are trying to create a deuces card game and we have bee stuck on that single problem. I have also looked for other similar problem that people have asked and we were not able to find the issue, it says that we have to put .new function to initialize the data. But the error is still showing up. Please help us!
You don't have a #game method in your GameController class.
Rename your #index action into #game or your View file.
I don't know how your routes file looks like but I suppose that the index action is the action that you call if somebody calls the root route, so http://localhost:3000/. If that's right then you have to rename game.html.erb into index.html.erb.
It looks like you are calling the action #game on controller Games. There is no #game method defined on the controller, so the instance variable #game never gets defined like it does in #index or #new. You can create a #game method in the controller and define #game in that method as needed.
Also, you have some code in the controller that needs to be inside of a method, starting at #game.add_player_from_user(current_user). Right now it's just executing at load time and probably not doing anything that makes any sense.
Finally, I noticed that you misspelled 'destroy' in a couple of places - search for 'destory' and replace with 'destroy' to avoid problems later.
I have three html pages.
In the first page, I view the list of data.
In the second page, I view the data of a particular element of the list.
In the third page, the user can edit data of a particular element of the list.
When the user submits the 'form', how can I redirect the user in the second page? I tried in this way:
render :action => "show_details",:id=>params[:id]
It works. The link is correct. But the page is not opened if I do not refresh the page.
UPDATE I
I write my code in this action in the reports controller:
def setFixed
rs=Report.find(params[:id])
rs.state ="1"
rs.save
render :action => "show_details",:id=>params[:id]
end
UPDATE II
Reports controller code:
class ReportsController < ApplicationController
before_filter :authenticate_user, :only => [:index,:show,:show_details,:new]
def stateDialog
render :stateDialog, :current_state=>params[:current_state]
end
def setFixed
rs=Report.find(params[:id])
rs.state ="1"
rs.save
render :action=>"show_details",:id=>params[:id]
end
def setNotFixed
rs=Report.find(params[:id])
rs.state ="0"
rs.save
render :action=>"show_details",:id=>params[:id]
end
def edit
#report=Report.find(params[:id])
end
def update
#report = Report.find(params[:id])
if #report.update_attributes(params[:report])
flash[:notice]=''
render :action=>"show_details",:id=>params[:id]
else
flash[:notice]=''
render :action=>"show_details",:id=>params[:id]
end
end
def deleteDialog
render "deleteDialog"
end
def focus_maps
render "focus_maps"
end
def delete
Report.find(params[:id]).destroy
render "show"
end
def index
#report=Report.new
end
def logged
render "new"
end
def show
render params[:page]
end
def new
#report=Report.new
end
def show_details
render "show_details"
end
def create
#report=Report.new( params[:report] )
if #report.save
flash[:notice]='Segnalazione avvenuta!'
else
flash[:notice]='Impossibile sottoporre la segnalazione!'
end
render "show"
end
end
I found advice that params must be filled before render calling, like this:
#id = params[:id]
render :action => 'show_details'
This solution is works for me, try it
If you want to redirect user somewhere you should use redirect_to
redirect_to action: 'show_details', id: params[:id]
The functionality I'm trying to build allows Users to Visit a Restaurant.
I have Users, Locations, and Restaurants models.
Locations have many Restaurants.
I've created a Visits model with user_id and restaurant_id attributes, and a visits_controller with create and destroy methods.
Thing is, I can't create an actual Visit record. Any thoughts on how I can accomplish this? Or am I going about it the wrong way.
Routing Error
No route matches {:controller=>"restaurants", :location_id=>nil}
Code:
Routes:
location_restaurant_visits POST /locations/:location_id/restaurants/:restaurant_id/visits(.:format) visits#create
location_restaurant_visit DELETE /locations/:location_id/restaurants/:restaurant_id/visits/:id(.:format) visits#destroy
Model:
class Visit < ActiveRecord::Base
attr_accessible :restaurant_id, :user_id
belongs_to :user
belongs_to :restaurant
end
View:
<% #restaurants.each do |restaurant| %>
<%= link_to 'Visit', location_restaurant_visits_path(current_user.id, restaurant.id), method: :create %>
<% #visit = Visit.find_by_user_id_and_restaurant_id(current_user.id, restaurant.id) %>
<%= #visit != nil ? "true" : "false" %>
<% end %>
Controller:
class VisitsController < ApplicationController
before_filter :find_restaurant
before_filter :find_user
def create
#visit = Visit.create(params[:user_id => #user.id, :restaurant_id => #restaurant.id])
respond_to do |format|
if #visit.save
format.html { redirect_to location_restaurants_path(#location), notice: 'Visit created.' }
format.json { render json: #visit, status: :created, location: #visit }
else
format.html { render action: "new" }
format.json { render json: #visit.errors, status: :unprocessable_entity }
end
end
end
def destroy
#visit = Visit.find(params[:user_id => #user.id, :restaurant_id => #restaurant.id])
#restaurant.destroy
respond_to do |format|
format.html { redirect_to location_restaurants_path(#restaurant.location_id), notice: 'Unvisited.' }
format.json { head :no_content }
end
end
private
def find_restaurant
#restaurant = Restaurant.find(params[:restaurant_id])
end
def find_user
#user = current_user
end
end
I see a lot of problems here. The first is this line of code in your VisitController's create action (and identical line in your destroy action):
#visit = Visit.create(params[:user_id => #user.id, :restaurant_id => #restaurant.id])
params is a hash, so you should be passing it a key (if anything), not a bunch of key => value bindings. What you probably meant was:
#visit = Visit.create(:user_id => #user.id, :restaurant_id => #restaurant.id)
Note that you initialize #user and #restaurant in before filter methods, so you don't need to access params here.
This line of code is still a bit strange, though, because you are creating a record and then a few lines later you are saving it (if #visit.save). This is redundant: Visit.create initiates and saves the record, so saving it afterwards is pretty much meaningless. What you probably want to do is first initiate a new Visit with Visit.new, then save that:
def create
#visit = Visit.new(:user_id => #user.id, :restaurant_id => #restaurant.id)
respond_to do |format|
if #visit.save
...
The next thing I notice is that you have not initiated a #location in your create action, but you then reference it here:
format.html { redirect_to location_restaurants_path(#location), notice: 'Visit created.' }
Since you will need the location for every restaurant route (since restaurant is a nested resource), you might as well create a method and before_filter for it, like you have with find_restaurant:
before_filter :find_location
...
def find_location
#location = Location.find(params[:location_id])
end
The next problem is that in your view your location_restaurant_path is passed the id of current_user and of restaurant. There are two problems here. First of all the first argument should be a location, not a user (matching the order in location_restaurant_path). The next problem is that for the _path methods, you have to pass the actual object, not the object's id. Finally, you have method: :create, but the method here is referring to the HTTP method, so what you want is method: :post:
link_to 'Visit', location_restaurant_visits_path(#location, restaurant.id), method: :post
You'll have to add a find_location before filter to your RestaurantController to make #location available in the view here.
There may be other problems, but these are some things to start with.
location_id is nil and the path definition doesn't say (/:location_id) forcing a non-nil value there in order to route to that path; create a new route without location_id if you can derive it from a child's attribute (i.e. a restaurant_id refers to a Restaurant which already knows its own location_id).