I'd like to use liquid in my Rails app. I've installed the gem. In order to use in all templates, I've created a library (lib/liquid_view.rb:):
class LiquidView
def self.call(template)
"LiquidView.new(self).render(#{template.source.inspect}, local_assigns)"
end
def initialize(view)
#view = view
end
def render(template, local_assigns = {})
#view.controller.headers["Content-Type"] ||= 'text/html; charset=utf-8'
assigns = #view.assigns
if #view.content_for?(:layout)
assigns["content_for_layout"] = #view.content_for(:layout)
end
assigns.merge!(local_assigns.stringify_keys)
controller = #view.controller
filters = if controller.respond_to?(:liquid_filters, true)
controller.send(:liquid_filters)
elsif controller.respond_to?(:master_helper_module)
[controller.master_helper_module]
else
[controller._helpers]
end
liquid = Liquid::Template.parse(template)
liquid.render(assigns, :filters => filters, :registers => {:action_view => #view, :controller => #view.controller})
end
def compilable?
false
end
end
And added the following initialiser (config/initializers/liquid_template_handler.rb:):
require 'liquid_view'
ActionView::Template.register_template_handler :liquid, LiquidView
PS: I've followed these instructions.
Now, if rename a template file with liquid my_template.html.liquid the <%= stylesheet_link_tag 'mycss' %> stopped working, but more importantly the {{user.first_name}} variable did not print. In my controller I have #user = current_user
What am I missing?
My intention is to completely override erb with liquid in some templates, so ideally it should work like erb (in a sense that I can pass variables from the controller and simply render it in the template without using Liquid::Template.parse(#page.template) which by the way, I don't understand how it works on a file-based template.
PS: I'm also using [this] gem (https://github.com/yoolk/themes_on_rails) for separate templates. I'm not sure it does any impact on it.
PPS: I've seen this but doesn't apply as its a older version of Rails and I'm not using prepend.
PPPS: I'm using Ruby 2.2.2 and Rails 4.2
I hope this not the problem you are thinking it is . You can check the way as it was said here Github Description
Did you create a Drop to access #user?
https://github.com/Shopify/liquid/wiki/Introduction-to-Drops
Liquid is a safe template system, so we can interpret on the backend templates that are created by the user. To access anything non trivial (number, string, hashes or arrays) you need a Drop, which is a controlled interface to define what the templates can access.
This is by design and for security reasons.
So, I'm starting an API from a new rails-api project.
I would like to use Devise for all the authentication stuff. I already learned a lot from my recent googling-sessions. I have a working SessionsController, however I noticed with the RegisterController that I certainly missed something about the duo Rails-API+Devise.
I still get the following error :
NameError (undefined local variable or method 'flash' for # <RegistrationsController:0x007ff6022b44b8>)`
From a pure API perspective should I keep working with Devise flash messages since I don't want to render views? I didn't included ActionDispatch::Flash based on the principe that I'll just render JSON. So, is there a way to properly deal with that case?
Thank you.
I would rather suggest to send messages in json instead of having flash[:messages]. If you are not dealing with views then go for json, flash is not required.
Something like:
render :json => {:message => "message", :data => data}
I am very new to rails and following a tutorial for RESTful API so let me excuse if it is of not very good quality as I am equally a starter for these kind of terminologies as well.
I created a controller kitten with a command rails g controller kitten index
and in the index method I posted this code -
class KittenController < ApplicationController
def index
require 'open-uri'
kittens = open('http://placekitten.com/')
response_status = kittens.status
response_body = kittens.read[559, 441]
puts response_status
puts response_body
end
end
and un commented match ':controller(/:action(/:id))(.:format)' in routes.rb
When i navigate through this - http://localhost:3000/kitten
this is what i am getting in my browser -
Kitten#index
Find me in app/views/kitten/index.html.erb
and this in my command line -->
Now my question why it so although i am expecting it in my browser but the cat is shown in command prompt instead of browser ..i am new to rest resource so please excuse if it is a bad one :(
I don't know what tutorial you're following, but doing this seems like a very odd thing to do for Rails in general and learning RESTful APIs in particular.
Anyway, the puts in your controller outputs text to Ruby's standard out, which is going to be the terminal where the server started. That's why this is appearing in the console rather than in your browser: puts is putting it there.
If you want this to appear in a web page, you'll need to make a view for that controller action. Perhaps following further along your tutorial will get you there: if not, you might want to find a better one.
You should read the Model-View-Controller rails guide.
Controllers provide the “glue” between models and views. In Rails, controllers are responsible for processing the incoming requests from the web browser, interrogating the models for data, and passing that data on to the views for presentation.
Define your variable in the controller and display it in the view:
class KittenController < ApplicationController
def index
#variable = 'Hello World'
end
end
In your view (app/views/kitten/index.html.erb):
<%= #variable %>
Rails controllers setup responses with a render call.
When the call is not performed it instantiates the appropriate view and renders that view. In your case that is index.html.erb
Try this:
render :text => kittens.read[559, 441], :status => kittens.status
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 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.