I wrote an app for shopify which works as designed. Now I wanted to add the app proxy to make the content embedded in the shop. The proxy is working fine but shopify expects a response (in my case a view) as pure liquid. The original view in ruby has some logic using several variables and objects.
I installed the liquid gem. The tutorials I walked through seem to be a little bit outdated.
#template = Liquid::Template.parse("hi {{name}}") # Parses and compiles the template
#template.render( 'name' => 'tobi' ) # Renders the output
=> "hi tobi"
This is working, but it only works with strings. I watched the railscast which I thought will be an easy way to allow liquid to access the objects. But again its outdated and the "liquid_methods" isn't working any more.
So i wrote my own method in my model:
def to_liquid
{ "title" => self.title,
"description" => self.description
}
If i try to render it with my method in my console like this:
#template = Liquid::Template.parse("Welcome to {{object.title}}")
#template.render(object.title.to_liquid)
I get the following error:
Liquid::ArgumentError (Liquid error: Expected Hash or Liquid::Context as parameter)
Now Im stuck...
What is the most simple way to access RoR Objects with liquid?
After trying almost every possible way to pass the variable, this did the trick:
#object = Object.find(params[:id])
#hash_object = #object.to_liquid
#template = Liquid::Template.parse("Welcome to {{object_title}}")
#template.render('object_title' => #hash_object["title"])
In my model I have:
after_create :push_create
I push_create I need to render a view. I'm trying to do that like so:
def push_event(event_type)
X["XXXXX-#{Rails.env}"].trigger(event_type,
{
:content => render( :partial =>"feeds/feed_item", :locals => { :feed_item => self })
}
)
end
This angers rails as it doesn't like me rendering a view in the model but I need it there.
Error:
NoMethodError (undefined method `render' for #<WallFeed:0x1039be070>):
Suggestions? Should I render it somewhere else somehow? Or how can I render in the model to set content? Thanks
proper solution
Well, "they" are right. You really have to do the rendering in a controller -
but it's fair game to call that controller from a model! Fortunately, AbstractController
in Rails 3 makes it easier than I thought. I wound up making a simple
ActionPusher class, working just like ActionMailer. Perhaps I'll get ambitious and
make this a proper gem someday, but this should serve as a good start for anyone else in my shoes.
I got the most help from this link: http://www.amberbit.com/blog/2011/12/27/render-views-and-partials-outside-controllers-in-rails-3/
in lib/action_pusher.rb
class ActionPusher < AbstractController::Base
include AbstractController::Rendering
include AbstractController::Helpers
include AbstractController::Translation
include AbstractController::AssetPaths
include Rails.application.routes.url_helpers
helper ApplicationHelper
self.view_paths = "app/views"
class Pushable
def initialize(channel, pushtext)
#channel = channel
#pushtext = pushtext
end
def push
Pusher[#channel].trigger('rjs_push', #pushtext )
end
end
end
in app/pushers/users_pusher.rb. I guess the require could go somewhere more global?
require 'action_pusher'
class UsersPusher < ActionPusher
def initialize(user)
#user = user
end
def channel
#user.pusher_key
end
def add_notice(notice = nil)
#notice = notice
Pushable.new channel, render(template: 'users_pusher/add_notice')
end
end
Now in my model, I can just do this:
after_commit :push_add_notice
private
def push_add_notice
UsersPusher.new(user).add_notice(self).push
end
and then you'll want a partial, e.g. app/views/users_pusher/add_notice.js.haml, which could be as simple as:
alert('#{#notice.body}')
I guess you don't really need to do it with Pushable inner class and the .push
call at the end, but I wanted to make it look like ActiveMailer. I also have a
pusher_key method on my user model, to make a channel for each user - but this
is my first day with anything like Pusher, so I can't say for sure if that's the right
strategy. There's more to be fleshed out, but this is enough for me to get started.
Good luck!
(this was my first draft answer, leaving it in because it might help someone)
I've got the general outline of a solution working. Like this, in your model:
after_create :push_new_message
private
def render_anywhere(partial, assigns = {})
view = ActionView::Base.new(ActionController::Base.view_paths, assigns)
view.extend ApplicationHelper
view.render(:partial => partial)
end
def push_new_message
pushstring = render_anywhere('notices/push_new_message', :message_text => self.body)
Pusher[user.pusher_key].trigger!('new_message', pushstring)
end
that is definitely working - the template is rendering, and gets eval()'ed on the client side successfully. I'm planning to clean it up, almost certainly move render_anywhere somewhere more general, and probably try something like this
I can see that pushes will need their own templates, calling the generally available ones, and I may try to collect them all in one place. One nice little problem is that I sometimes use controller_name in my partials, like to light up a menu item, but I'll obviously have to take a different tactic there. I'm guessing I might have to do something to get more helpers available, but I haven't gotten there yet.
Success! Hooray! This should answer your question, and mine - I'll add more detail if it seems appropriate later. Good luck!!!!
original non-answer from an hour ago left for clarity
I don't have an answer, but this timely question deserves more clarification, and I'm hoping to get closer to my answer by helping ask :)
I'm facing the same problem. To explain a little more clearly, Pusher asynchronously sends content to a connected user browser. A typical use case would be a showing the user they have a new message from another user. With Pusher, you can push a message to the receiver's browser, so they get an immediate notification if they are logged in. For a really great demo of what Pusher can do, check out http://wordsquared.com/
You can send any data you like, such as a JSON hash to interpret how you like it, but it would be very convenient to send RJS, just like with any other ajax call and eval() it on the client side. That way, you could (for example) render the template for your menu bar, updating it in its entirety, or just the new message count displayed to the user, using all the same partials to keep it bone-DRY. In principle, you could render the partial from the sender's controller, but that doesn't make much sense either, and there might not even be a request, it could be triggered by a cron job, for example, or some other event, like a stock price change. The sender controller just should not have to know about it - I like to keep my controllers on a starvation diet ;)
It might sound like a violation of MVC, but it's really not - and it really should be solved with something like ActionMailer, but sharing helpers and partials with the rest of the app. I know in my app, I'd like to send a Pusher event at the same time as (or instead of) an ActionMailer call. I want to render an arbitrary partial for user B based on an event from user A.
These links may point the way towards a solution:
http://blog.choonkeat.com/weblog/2006/08/rails-calling-r.html
How to render a Partial from a Model in Rails 2.3.5
http://mattwindsurfs.wordpress.com/2008/06/19/rails-render-in-a-model/
http://davetroy.blogspot.com/2008/02/actsasrenderer-brings-output-to-models.html
https://github.com/asapnet/acts_as_renderer
http://ethilien.net/archives/render-rails-templates-anywhere-even-in-a-model/
The last one looks the most promising, offering up this tantalizing snippet:
def render_anywhere(partial, assigns)
view = ActionView::Base.new(Rails::Configuration.new.view_path, assigns)
ActionView::Base.helper_modules.each { |helper| view.extend helper }
view.extend ApplicationHelper
view.render(:partial => partial)
end
As does this link provided by another poster above.
I'll report back if I get something working
tl;dr: me too!
I just do this:
ApplicationController.new.render_to_string(partial: 'messages/any', locals: { variable: 'value' })
Rails 5 way
In Rails 5 rendering outside a controller became pretty straightforward due to implemented render controller class method:
# render template
ApplicationController.render 'templates/name'
# render action
FooController.render :index
# render file
ApplicationController.render file: 'path'
# render inline
ApplicationController.render inline: 'erb content'
When calling render outside of a controller, one can assign instance variables via assigns option and use any other options available from within a controller:
ApplicationController.render(
assigns: { article: Article.take },
template: 'articles/show',
layout: false
)
Request environment can be tailored either through default options
ApplicationController.render inline: '<%= users_url %>'
# => 'http://default_host.com/users'
ApplicationController.renderer.defaults[:http_host] = 'custom_host.org'
# => "custom_host.org"
ApplicationController.render inline: '<%= users_url %>'
# => 'http://custom_host.org/users'
or explicitly by initializing a new renderer
renderer = ApplicationController.renderer.new(
http_host: 'custom_host.org',
https: true
)
renderer.render inline: '<%= users_url %>'
# => 'https://custom_host.org/users'
Hope that helps.
You can use ActionView directly and render partials to string without having a controller. I find that pattern useful to create models that encapsulate some javascript generation, for instance.
html = ActionView::Base.new(Rails.configuration.paths['app/views']).render(
partial: 'test',
formats: [:html],
handlers: [:erb],
locals: { variable: 'value' }
)
Then, just put your _test.html.erb in you view folder and try it out!
Rails 6.0.0 compatible answer, since I ended up on this page while searching for a solution:
lookup_context = ActionView::LookupContext.new(Rails.configuration.paths["app/views"])
renderer = ActionView::Base.new(lookup_context)
renderer.extend(Rails.application.helpers)
renderer.render \
template: "foo/bar",
formats: [:html],
handlers: [:erb],
locals: { user: User.new }
I'm fairly sure the answers you seek lie within Crafting Rails Applications where Jose Valim goes into great detail about how and why you would want to render views straight from your db
Sorry I can't be of more help yet because I've just started reading it myself tonight.
You might find some help here - it's a blog post about doing this sort of thing, albeit using different methods than yours
the "proper" way to do this is to push an object in serialized form(json), and then have the view deal with it once the event is received. Perhaps you want to use Handlebars to render the object.
Edit: I originally wrote about how, despite my answer, I was going to follow your example. But I just realized there is a HUGE gotcha with your approach when it comes to push notifications.
In your problem, you are doing push notifications to one user. For me, I was broadcasting out to a set of users. So I was going to render html with a presumption of a "current_user" and all that comes with it(eg logic, permissions, etc). This is NO BUENO as each push notification will be received by a different "current user".
Therefore, really, you need to just send back the data, and let each individual view handle it.
You should call all render methods from a controller. So, in this case, you can notify the controller that the object has been created and the controller can then render the view. Also, since you can render only once, I think you can wait for all your server side operations to complete before invoking the render.
The render methods are defined on the ActiveController class and its progeny. Inherently you do not have access to it on the model, nor is it a class method so you can't use it without an instance of the controller.
I've never tried to instantiate a controller for the express purpose of simply stringifying a partial, but if you can get your hands on a controller, render_to_string seems to be the way to go.
I will chime in by saying that if you're going down this path you're taking RoR "off the Rails". This is a violation of MVC and fundamentally poor program design.This doesn't mean I think you're a bad person :P Sometimes life drives us off the rails, so to speak.
I can't speak to the details that have driven you to do this, but I'd strongly suggest you rethink your approach.
I have created a gist for this.
I needed something similar, where the models don't necessarily (or in my case, ever) get updated via a controller, so the logic can't sit there.
Created a server-push based controller:
https://gist.github.com/4707055
I use one layout for all my emails in my Notifier model (20+ emails)... however sometimes I just want to send a plain text email with no layout or html at all. I can't seem to be able to figure out how? If I try to send a plain text email i still get the layout, and all the HTML in the email.
I'm using Rails 2.3.8.
I read about this monkey patch here... but it seemed to indicate a newer version of rails had over come this? And I don't really wanna monkey patch if I can avoid one.
Rails - setting multiple layouts for a multipart email with mailer templates
layout "email" # use email.text.(html|plain).erb as the layout
def welcome_email(property)
subject 'New Signup'
recipients property.email
from 'welcome#test.com'
body :property => property
content_type "text/html"
end
def send_inquiry(inquire)
subject "#{inquire.the_subject}"
recipients inquire.ob.email
from "Test on behalf of #{inquire.name} <#{inquire.email}>"
body :inquire => inquire
content_type "text/plain"
end
I also have 2 files.
email.text.html.erb
email.text.plain.erb
It always uses text.html.erb... even if the content_type is "text/plain"
edit: Figured it out, the layouts follow a different naming scheme to the email templates. Just rename them as follows:
layout.text.html.erb => layout.html.erb
layout.text.plain.erb => layout.text.erb
I also made the mistake of manually defining the parts, if you use this:
part :content_type => 'text/plain',
:body => render_message('my_template')
Then Rails can't determine the content_type for your part and it assumes it's HTML.
After I changed those two things it worked for me!
original reply follows..
I've struggled with this question many times in the past, usually ending up with some sort of non-dry quick and dirty solution. I always thought I was the only one with this problem because Google turns up exactly nothing useful on the subject.
This time I decided to dig into Rails to figure it out but so far without much success, but maybe my findings will help someone else figure this out.
What I found was that in ActionMailer::Base the #render_message method is tasked with determining the proper content_type and should assign it to #current_template_content_type. #default_template_format then either returns the proper mime type for the layout or, if #current_template_content_type isn't set, it will default to :html.
This is what ActionMailer::Base#render_message looks like in my app (2.3.5)
def render_message(method_name, body)
if method_name.respond_to?(:content_type)
#current_template_content_type = method_name.content_type
end
render :file => method_name, :body => body
ensure
#current_template_content_type = nil
end
The trouble is that method_name appears to be a string (the name of the local view, in my case "new_password.text.html") and strings of course do not respond_to #content_type, meaning #current_template_content_type will always remain nil, and so the #default_template_format will always default to :html.
Not much closer to an actual solution, I know. The ActionMailer internals are just too opaque for me.
OK, not sure if this works, but it seems the default content_type is text/plain, so you would only need to set the content type if you want something other than text/plain.
Try this:
def send_inquiry(inquire)
subject "#{inquire.the_subject}"
recipients inquire.ob.email
from "Test on behalf of #{inquire.name} <#{inquire.email}>"
body :inquire => inquire
end
I still think you should consider this:
layout "email", :except => [:send_inquiry]
I would use the above because the plain text email does not seem to have a 'layout', only the actual content you want to send.
I found this that I think could be useful.
http://blog.blazingcloud.net/2009/11/17/simple-email-form-with-actionmailer/
He makes use of renaming the view templates for different content types.
I have a Rails 2.3.5 application and Im trying to render several Partials from within a Model (i know, i know -- im not supposed to). The reason im doing this is im integrating a Comet server (APE) into my Rails app and need to push updates out based on the Model's events (ex. after_create).
I have tried doing this:
ActionView::Base.new(Rails::Configuration.new.view_path).render(:partial => "pages/show", :locals => {:page => self})
Which allows me to render simple partials that don't user helpers, however if I try to user a link_to in my partial, i receive an error stating:
undefined method `url_for' for nil:NilClass
I've made sure that the object being passed into the "project_path(project)" is not nil. I've also tried including:
include ActionView::Helpers::UrlHelper
include ActionController::UrlWriter
in the Module that contains the method that makes the above "render" call.
Does anyone know how to work around this?
Thanks
We use the render_anywhere gem and have been happy with it.
From the README:
require 'render_anywhere'
class AnyClass
include RenderAnwhere
def build_html
html = render :template => 'normal/template/reference',
:layout => 'application'
html
end
end
Including these two modules should be enough. Maybe you forgot to set default_url_options[:host]? Without it you can use _path helpers, but not _url ones.
Include these modules and check out if it works in irb, maybe it will lead you to right solution.
I am using Authlogic to do some simple signup and login stuff. In my WelcomeController I want to have the signup and login forms on the same page 'index' with form actions set to their individual controllers, UsersController and UserSessionsController, respectively. These controllers redirect the user to the protected profile page within the site on successful signup/login. On error I need to redirect back to the WelcomeController#index and display their errors. Upon doing a redirect this information is lost and I cannot use a render because it is a different controller. What is the correct way to handle this behavior?
I could perhaps store the error messages in the Flash Hash. This seems like the easiest solution.
Lately I have stumbled across this problem in another application I was writing where I needed to render summary pages from researcher submitted RFP forms from a PeerReviewerController. Seemed like in that case the use of now deprecated components would have been the right way to handle this. ie: render_component :controller => 'RFPForms', :action => 'summary', :id => 213
Components seem like the DRY way to do something like this. Now that we don't have them what is the correct solution?
One simple and easy way to do this is to pass a parameter on the redirect:
redirect_to welcome_url(:login_error=>true)
In your view or controller you can then test for that param:
<% if params[:error] -%>
<div class="error">My Error Message</div>
<% end -%>
You could do a render:
render :template => "welcome/index"
But you'd have to make sure that any variables that page expects are loaded, or it won't render.
Drew's answer does not cater for more complex error data (e.g. an array of validation errors), and Marten's answer would risk violating the DRY rule by needing to duplicate code from WelcomeController#index.
A better-looking answer (which is an elaboration on the original poster's idea of storing error data in the flash) is available in Rails validation over redirect although unfortunately I am still personally struggling to get it working ...