Rails 5: Merging parameters in view - where to permit them? - ruby-on-rails

what is the new way in Rails 5 to merge actual page query strings to link with a new one?
Let's assume I have page http://localhost:3000?type=a and I want to add another query param to the link on page:
<%= link_to root_path(params.merge(tech: "b")) do %>
but I get: unable to convert unpermitted parameters to hash.
Where I should permit the params?
I tried to do it in before_action filter, but it seems to be too late.
Thanks
EDIT:
My controller:
class HomeController < ApplicationController
before_action :permit_params
...
private
def permit_params
params.permit(:tech, :type)
end
end

You just need to whitelist the params you want to merge with
<%= link_to 'Home', root_path(params.permit(:type, :tech).merge(tech: 'b')) %>
and get /?tech=b&type=a. If you really want all parameters, you can use permit!
<% params.permit! %>
<%= link_to 'Home', root_path(params.merge(tech: 'b')) %>
which will give you /?action=index&controller=home&tech=b&type=a, which while those keys don't seem to be messing anything up, is very likely not desired (and controller and action will be overridden and not passed into your controller action). NOTE: The controller/action are set that way because I'm on my HomeController index action, not because that's what root_path is pointing to
I just don't think I can recommend doing this, however (seems iffy, imo)...stick with whitelisting.

Related

Access params hash from other action in same controller wihtout reset

class UsersController < ApplicationController
def newpass
#somevariable = {
"a-var" => params[:token_id],
"b-var" => params[:client_id],
"c-var" => params[:user_id]}
end
def setpass
#I need to access this hash values without params getting reset
end
end
I have an action newpass with a corresponding view which calls setpass. I access URL's params in newpass action. I want to use these param values in setpass but the values get reset.
Using a link:
You need to send those values when your request hits setpass action in UsersController. You can create a button, or a link_to to send along those params values. Here is how:
<%= link_to "Go to", setpass_path(token_id: params[:token_id]) %>
You can pass params in _path method, and you will receive all those values inside the respective method in controller.
Using a form:
If you are using a form, and you would like to send those values along, hidden_field_tag is the best option here. You can do something like this:
<%= hidden_field_tag :token_id, params[:token_id] # this line must exist inside your form element %>

I want to use one controller and html.erb files for my dynamic table. How I will do it in Ruby On Rails?

I stored all the tablename I've created to Menu table. And every time I add the table in Menu, it will automatically create a link under Menu list
see below.
I want each table in Menu to have a Listing, New, Edit, and Delete.
see below.
I have a controller prj_menus_controller, I will just pass the id of the table from Menu table.
here is the code for index and new in my controller.
Class PrjMenusController < ApplicationController
def index
#prj_menus = Menu.find(params[:id]).tablename.singularize.classify.constantize.all
end
def new
#prj_menu = Menu.find(params[:id]).tablename.singularize.classify.constantize.new
end
def create
#prj_menu = Menu.find(params[:id]).tablename.singularize.classify.constantize.new(prj_menu_params)
if #prj_menu.save
redirect_to :action => 'index'
else
render :new
end
end
private
def prj_menu_params
params.require("HERE IS MY PROBLEM").permit(:name)
end
end
and in my
new.html.erb
<%= simple_form_for (#prj_menu),:url => prj_menus_path, :method => :post do |f| %>
<%= f.input :name %>
<%= f.submit 'Save', class: 'btn btn-primary' %>
<%= link_to "Cancel", :back, {:class=>"btn btn-default"} %>
<% end %>
I can get the list in my index.html.erb, it is working. My problem is that I don't know how to get all params when I click the submit in new.html.erb. I got this hash
{"sample1_table"=>{"name"=>"test 6"}, "commit"=>"Save","controller"=>"prj_menus", "action"=>"create"}
It is correct but I don't know what to put in my controller. I tried this params.require(["#{#prj_menu}"]).permit(:name), it creates new record but params[:name] does not save.
I am still a noob to Ruby On Rails and I don't know what to search for this.
I think you are mostly confused on what parameter whitelisting does and how parameters are passed from the form to the controller.
I does not really matter if the name of the form hash matches the name of the database table. It just does in most cases since that makes the most sense. It's simply representative of the REST interface of your app.
Let's say you have a action which creates Pets:
POST /pets
And in our form we have a bunch of inputs like so:
<input name="pet[name]">
Rails will map create a params[:pet] hash { name: 'Spot' }. But we want to save the pets as an Animal.
class PetsController < ApplicationController
def new
#pet = Animal.new()
end
def create
#pet = Animal.new(pet_params)
if #pet.save
# ...
end
def pet_params
params.require(:pet).permit(:name)
end
end
Animal does not care what the params key is, it just gets a hash. But we also need to tell simple_form what parameter key we want to use since it looks at the model_name attribute.
simple_form_for(#pet, as: :pet)
Gives us pet[name] instead of animal[name].
I don't get why you are so adamant about making things so difficult for yourself though unless you are creating a database administration tool in the vein of PHP_MyAdmin. And even that case you don't even want to be altering the schema of the app database at runtime.
You are going to run into huge problems when it comes to creating effective queries for getting all the menus.

pass value of td element to rails controller

I'm trying to pass the value of a element to a rails controller!
Currently, I have something like this:
<td id="dbname"><%= link_to db, :action => :show %></td>
This represents a row in an html table, which contains a string value, e.g. "development".
When the user clicks on the "development" link, the <%= link_to ... %> grabs the value from the current clicked and passes that to a rails controller action, in this case the show action.
How can this be achieved!?
UPDATE - generating links:
<% #dbs.each do |db| %>
<tr>
<td id="dbname"><%= link_to db, :action => :show %> </td>
</tr>
UPDATE 2:
this is my index controller:
conn = Mongo::Connection.new
#dbs = conn.database_names #this returns an array of strings (which are the names of the databases)
Now I want to be able to click on of these databases and then to pass the clicked text to the rails controller show action. I'm not sure how I would generate a custom resources path for these links... but I was contemplating of doing it using Ajax or something javascript related. Maybe get the text of clicked link using jQuery and then send an Ajax request to the rails controller with the text as a parameter!
I think that it's a strange thing what you're trying to do, but a solution could be to use javascript to append the id to the href of each link as a query string.
If you could explain a little bit what you're trying to achieve maybe we could find a better solution.
Hope it helps!
Edit:
If you have a table of links I think that you should consider them as a resource and managing them the REST way.
Your controller should have an index and show action and you should declare the links as a resource in the routes file (maybe link it's a reserved word and you will have to use a different name, I'm not sure), the index action will fetch all the links and when you render them, you could specify the link for each one with something similar to "link_path(link.id)" (remember, you should have a show action defined) in the controller you will receive the link id so you could load it with a simple "find" and pass it to the view.
I recommend you to always look for the REST way to solve a problem in ROR.
Edit 2:
Ok let's see if this works for you:
I suppose that you have a model that represent those links that you're talkin about, for example:
class DataBaseLinks < ActiveRecord:Base
end
This model with be backed up by a table in your database, if you have generated it the rails way, you will also have an id column that identify each database link.
in your controller, let's say DataBaseLinksController, you'll have:
class DataBaseLinksController < ApplicationController
def index
#dabatase_links = DataBaseLink.all
end
def show
#database_link = DataBaseLink.find(params[:id])
end
end
(I've avoided all the validations and checks).
All you have to do in your index.html.erb is:
<% #database_links.each do |database_link| %>
<%= link_to database_link.name, database_link_path(database_link.id) %>
<% end %>
This will generate all the links with the correct path to the show action (maybe the route helper is a little bit different, but not so much).
Notice also that you'll have to add into your routes.rb the following line:
resources :database_links, :only => [:index, :show]
How do you see it?
Edit 3:
(I'll delete all my edited answers when we find a correct one)
Ok I'm going to suppose that you are not using something like mongoid so you don't have active record similar objects.
Have you tried this in your view:
<% dbs.each do |dbs_name| %>
<%= link_to dbs_name, :controller => "your_controller", :action => :show, :dbs_name => dbs_name %>
<% end %>

ransack search form in header partial: No Ransack::Search object was provided to search_form_for

First of all, I'm new to RoR, so the answer may be obvious, in which case I apologize. I've looked around and haven't found anything that helps.
I'm trying to have a search form at the header of every web page on my app that will search through the names of all my "buckets". Here is the relevant code:
In app/views/layouts/_header.html.erb (within a nav bar):
<% search_form_for #q do |f| %>
<%= f.label :name_cont %>
<%= f.text_field :name_cont %>
<%= f.submit %>
<% end %>
In app/controllers/buckets_controller.rb:
def index
unless params[:q].blank?
#q = Bucket.search(params[:q])
#buckets = #q.result.paginate(:page => params[:page])
else
#buckets = Bucket.find(:all, :limit => 5).paginate(:page => params[:page])
end
end
I understand the last part isn't that great: what I'm trying to do is if I'm just accessing the bucket index page (not by searching), i display the 5 most recently created buckets. When I search for something in the header form, I access the index page but only show the buckets that hit the search. (would a better way to handle it to have a search page separate from my index page?)
I found this issue which is pretty much identical, but I still don't see how I handle #q if every page is going to have the form on it--surely I don't have to alter every controller's every action?
Sorry in advance for any frustration my noobishness my cause you!
As others have said, you need to utilize the ApplicationController's before_filter. Though ernie himself seems not to recommend this, the implementation is simple.
First, use the advanced Ransack options to set your path for your search thusly
#config/routes.rb
resources :buckets do
collection do
match 'search' => 'buckets#search', via: [:get, :post], as: :search
end
end
Second, update your BucketsController to include the following custom action:
#controllers/buckets_controller.rb
def search
index
render :index
end
Nothing yet out of the ordinary. If you currently try to search you will get the error from your original question. Your definition of the variable q is correctly implemented, but you will have to move it to the ApplicationController like so:
#controllers/application_controller.rb
before_filter :set_global_search_variable
def set_global_search_variable
#q = Bucket.search(params[:q])
end
Finally, update your search form to pass in the correct search options
#layouts/_header.html.erb
<% search_form_for #q, url: search_buckets_path, html: { method: :post } do |f| %>
<%= f.label :name_cont %>
<%= f.text_field :name_cont %>
<%= f.submit %>
<% end %>
No, you do not need to edit all your controllers.
You can use ApplicationController for all your "common" controller needs. Read up on it in the guides http://guides.rubyonrails.org/action_controller_overview.html and the API docs http://api.rubyonrails.org/classes/ActionController/Base.html
The key here is, when you generated your new rails app, you'll notice it created the file .../app/controllers/action_controller.rb and that class derives from ActionController::Base. Then, if you again use the rails generator to create a controller for your app, you'll notice your new controller class derives from ApplicationController (not ::Base). That means that the application_controller.rb is the parent controller class for your app. That means everything in it is available to all your app controllers. It's easy to abuse, so be judicious.
Looks like this is not possible. This is a comment from Ernie the gem author.
You'd have to handle the Ransack-required stuff in a before_filter or
(ick) in the view partial itself. If you're putting a search field on
every single part of the site, I'd recommend you strongly consider
whether ransack is the right tool for the job, as well. You might want
some sort of inverted index search setup like sphinx, solr, etc.
https://github.com/ernie/ransack/issues/3

Post Params to External Site with Link_to

I have a shop application and another site thats for a special promotion. I've used Active Resource to import products from the shop in to the promo site and added a shopping cart to add the products. However, to actually order the products I need to send the items to the shop application, creating a new cart there to finish the order.
I've made a demo 'RESTful' application to practice using xml to send data back and forth, so I'm trying to use the principles of REST for the real app. However, I need to send the products to a non-RESTful controller. Just to give you an idea of the Cart controller in the shop, here are its actions:
def index…
def add…
def checkout…
def update…
def remove…
def empty…
def apply_discount…
def remove_discount…
def apply_credits…
def remove_credits…
def stock_check…
# My action to accept items from carts in other apps
def cart_import…
And in routes.rb, the only route relating to the cart is currently
map.cart 'cart/:action/:id', :controller => 'shop/cart'
I've inherited the shop application from a previous developer, so I'd probably try to make it more RESTful if I was to make it from scratch.
Anyway, I'm pretty confident that I can get the cart to respond to XML, even without being defined with map.resources. My problem is how to send a hash of the cart items and quantities from the promo app.
To group the cart items and quantities I've collected the item's product id and quantity in to a hash:
<% #items = Hash.new %>
<% #cart.items.collect {|i| #items[i.product_id] = i.quantity} %>
Which when inspected gives the following output:
<%= Rails.logger.info #items.inspect %>
{1144=>2, 1143=>1}
So I figured to send them to the shop I could pass them in a posted link_to:
<%= link_to 'Export Cart', "http://shop.example.com/cart/cart_import", :items => #items, :method => :post %>
That doesn't seem to do anything, whereas omitting the first field appends the items to the URL in a format that looks sensible, but appears as a relative link on the promo application:
<%= link_to "http://shop.example.com/cart/cart_import", :items => #items, :method => :post %>
http://promo.example.com/cart?items[1143]=1&items[1144]=2&method=post
I'm sure the clue is in that the #items object needs to be passed in with the url, but since I can't use a named route I don't really know how to get it in there so that it is posted in the correct format.
Thanks for the help,
Gareth
the way you are passing in the parameters for the link_to method is assuming that :items is one of the link_to options, not one of the url options. this is an order of precedence issue and if you wrap your url inside parens then you can use the options available for the url_for method on your url, to build the path: http://apidock.com/rails/ActionView/Helpers/UrlHelper/url_for
You can't use a link to generate a POST request. It is turning to a GET request. Better use javascript to generate a post request on click of a button or some other event.
In the end I made a helper:
def hash_to_params(items)
result = ""
i = 0
items.each do |item|
i > 0 ? result += "&" : result += ""
result += "items[#{item[0]}]=#{item[1]}"
i += 1
end
return result
end
Then for the link I called the helper:
<%= link_to "export", "http://shop.example.com/cart/cart_import?#{hash_to_params(#items)}", :method => :post %>
Pretty ugly way of doing it, but I really can't think of anything better?
Cheers,
Gareth

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