I'm trying to find the best way to execute a method in a Rails application.
I have the following in my model:
class Tweet < ActiveRecord::Base
def self.fetch_all
# do something
end
end
I can go to my Rails console and run Tweet.fetch_all and it executes everything inside this method. However, I'd love to create an link in my application to execute this fetch inside the view. Would I need to create a new action inside my controller to get to this?
Actions are executed by controllers, so you need to define an action in tweets_controller.rb:
def fetch_all
Tweet.fetch_all #what do you want to do with this?
redirect_to :back, notice: 'just called fetch_all'
end
and define a way to get to this action in routes.rb
post 'tweets/fetch_all', to: 'tweets#fetch_all'
Then you can use
<%= link_to 'Fetch all!', fetch_all_tweets_path, method: :post %>
anywhere in your views.
Yes, if you want to create a separate link to execute this function, you will need to first create an action inside the controller for this purpose, and then later, you can create a helper method or simply, use link_to to place the link in your views.
Reason being that, if you add this method inside some other REST action, this fetch will be performed whenever that action is rendered, and this might not be what you intend.
Therefore, you should create another action that specifically executes this code for you, thereby, allowing you to specifically execute this method, whenever the user clicks that link.
Related
I have a counter in my model that I want to give the user the ability to
reset it, I'm wondering what's the best way to achieve this. I can think of
two ways:
By a custom controller action.
Simple and easy but I can't decide which HTTP verb to use. I can make the
case that it should be a GET because the user clicks a link that reset
the counter and the result are always the same, i.e. counter
becomes 0. But it could also be a POST/PATCH since we are modifying
something on the server but POST/PATCH requires a form which leads to
the other way.
By a link that submits an edit form with the counter reset to 0 without
the user seeing the form.
I like this solution because it can be done with RESTful controller
methods. But I have no idea how to do that with Rails, or even if it's
possible.
So which is "Rails Way" to do this? and how do I do it?
Rather than creating a custom action, another approach is to create a well-named controller and stick to the RESTful controller method names.
config/routes.rb
resource :counter_reset, only: [:create]
app/controllers/counter_reset_controller.rb
class CounterResetController < ApplicationController
def create
# reset your counter
end
end
Then POST to counter_reset_path in your view
Personally, I would use button_to — this generates a single button that submits to the URL; it performs a POST operation by default. If you don't like the button style, you can switch to using link_to; however, keep in mind that if a user has JavaScript disabled, the request will fallback to using GET.
<%= button_to "Reset counter!", counter_reset_path %>
<%= link_to "Reset counter!", counter_reset_path, method: :post %>
http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-button_to
http://api.rubyonrails.org/classes/ActionView/Helpers/UrlHelper.html#method-i-link_to
Update:
If you prefer not to create a new controller, you can create a new route that maps to a custom action in your existing controller:
config/routes.rb
resources :counters do
post :reset, to: "counters#reset"
end
app/controllers/counters_controller.rb
class CountersController < ApplicationController
def reset
# reset your counter
end
end
In your view:
<%= button_to "Reset counter!", counter_reset_path %>
Actually you don't need a form, for me i would add a new action, it would look something like this ( of course depends on how your current routing looks like )
/user/:id/counter/reset # with action = post
And the link is very simple, you just create a link_to and add a method: :post which will add a data-method: :post in the html, the rest will be handled by the unobtrusive js.
The reason I don't recommend the form method, is users might use it to update different attributes that you might not want to update, or at least even change the counter to whatever number they want, I prefer the specific number to be defined in the controller not the view/form.
In Rails, I'd like to skip the "new" method in a controller entirely and go directly to the create method. (I don't need any form data to be submitted, and just want to go directly to creating the object based on data from the currently logged in user.)
In rake routes, I don't see a prefix that allows me to link directly to the controller's create method, so I think I should link to the new method and have that redirect to the create action without accepting any input.
I tried doing this with the following:
def new
create
end
def create
#request = Request.new
#request.requestor_id = current_user.id
#request.status = "S1"
#request.save
respond_with(#request, :location => "/products/findexchanges")
end
When browsing the DB, I can see that this is calling the create action and is adding the record to the db, but after it is done it is redirecting me to new.html.erb rather than the location defined at the end of the create method.
A create action should be triggered by a POST, not GET, which is why there is no specific route for it.
Use button_to instead of link_to. I tried using link_to and even after specifying method: :post, action: :create, it still takes me to index using GET. After using button_to and passing params in ####_path, it directly went to the create method and added data to database. Although I am not sure its correct way or safe way to do this.
So, I tried searching (a lot :( ) and haven't been able to find anything to help.
I feel like this is something I've done before, but I just can't seem to figure it out.
I have installed a gem (Recommendable, yay!), that allows me access to a bunch of methods(?):
user.like(movie)
=> true
In a view, I tried putting <%= link_to "Like", #user.like(#movie) %>... however, this seems to actually just run #user.like(#movie) on page load... automatically setting that user to like that movie.
What am I missing? :\
Much thanks in advance!
You want to have a a LikesController for stuff like this I guess. And then you can remote link to the create action and inside this create action you can actually do the like you want to do:
class LikesController < ApplicationController
def create
# assuming you have some method to get you the current_user
# and assuming you just want to like movies
movie = Movie.find_by_id(params[:id])
current_user.like(movie) if movie
# maybe check for success and return some meaningfull message
end
end
and then inside the view you can do:
<%= link_to "Like", likes_path(#movie), remote: true %>
This should trigger the like.
Don't forget to create a route in routes.rb for the LikesController.
You should always keep in mind, that for an action a user should be able to take, you need an action in a controller. The view always just presents a given state to the user with options to take action.
I currently have a form (using form_tag). One of the fields is a dropdown list of options. Each option value matches the name of a method in my controller. What I want to do is when the form submit button is clicked, it runs the controller method corresponding directly to the value selected in the dropdown field.
I've built a work-around right now, but it feels too verbose:
def run_reports
case params[:report_name]
when 'method_1' then method_1
when 'method_2' then method_2
when 'method_3' then method_3
when 'method_4' then method_4
else method_1
end
# each method matches a method already defined in the controller
# (i.e. method_1 is an existing method)
I had thought that it may work to use the dropdown option value to run the corresponding method in my controller through the form_tag action (i.e. :action => params[:report_name]), but this doesn't work because the action in the form needs to be set before the params value is set. I don't want to use javascript for this functionality.
Here is my form:
<%= form_tag("../reports/run_reports", :method => "get") do %>
<%= select_tag :report_name, options_for_select([['-- Please Select --',nil],['Option 1','method_1'], ['Option 2','method_2'], ['Option 3','method_3'], ['Option 4','method_4']]) %>
<%= submit_tag "Run Report" %>
<% end %>
Any suggestions?
Can I change my controller method to look something like this - but to actually call the controller method to run? I'm guessing this won't run because the params value is returned as a string...
def run_reports
params[:report_name]
end
WARNING: this is a terrible idea
You could call the method via a snippet of code like this in the controller:
send(params[:report_name].to_sym)
The reason this is a terrible idea is that anyone accessing the page could manually construct a request to call any method at all by injecting a request to call something hazardous. You really, really do not want to do this. You're better off setting up something to dynamically call known, trusted methods in your form.
I think you should rethink the design of your application (based on the little I know about it). You have a controller responsible for running reports, which it really shouldn't be. The controllers are to manage the connection between the web server and the rest of your app.
One solution would be to write a new class called ReportGenerator that would run the report and hand the result back to the controller, which would run any of the possible reports through a single action (for instance, show). If you need variable views you can use partials corresponding to the different kinds of reports.
As for the ReportGenerator, you'll need to be a little creative. It's entirely possible the best solution will be to have an individual class to generate each report type.
I have a method in one of my models that, when called, fetches a tweet using the twitter gem and stores some parts of it. I'd like to be able to trigger that action from the web interface to my app. What is the Rails Way to accomplish this? I've seen some references to not calling model methods from views, so should I be doing this from within a controller somehow instead?
My method (the relevant models are Sponsor and Sponsortweet (so my model name wouldn't conflict with Tweet, from the gem):
def create_tweet
tweet = Twitter.user_timeline(self.twitter).first
self.sponsortweets.create!(content: tweet.text,
tweet_id: tweet.id,
tweet_created_at: tweet.created_at,
profile_image_url: tweet.user.profile_image_url,
from_user: tweet.from_user,)
end
EDIT:
I created a tweet method in my sponsors controller:
def tweet
#sponsor = Sponsor.find(params[:id])
#sponsor.create_tweet
end
and added the following to my config/routes.rb: match 'tweet', to: 'sponsors#tweet', via: :post.
As well as the following code in my view (I'm using haml):
= button_to :tweet, tweet_path(#sponsor)
However, clicking the button results in the following error:
Couldn't find Sponsor without an ID
Your view should have a button that posts to a specific route in your controller. That controller would then call the method in your model. Having no idea what your app actually looks like, here's an example:
EDIT includes better example
View (assuming it's a Sponsor view):
<%= button_to :submit, tweet_path %>
Controller:
def tweet
Sponsor.create_tweet
end
And your model would stay the same, except you'd change your method to a class method like so:
def self.create_tweet
...your code here...
end
Since it seems this isn't tied to any particular sponsor, you'll use a class method and thus don't need an instance of the class to call your method. That said, it seems like you would want an instance of your class at some point...
I'd be curious to hear other people's answers, as I'm now wondering if there is such a way to bypass the controller all-together.
However, my take on this is that, since Rails is an MVC (Model View Controller) framework, I think the Rails way of accomplishing what you're considering is probably to simply handle the action normally; through the controller to the model.
If I am correct in assuming you have a button or link, or perhaps some AJAX, which is initiating the server-side Twitter processing, then I would set up your routing for that URL to point to a controller action method, which would then call your model method myModel.create_tweet.