I have a scenario where I'd like to pass back a long message with my JSON. Instead of writing it out with string concatenation I'd rather put together an erb template that I can render into my JSON. Below is the code I'm currently trying:
object #invitation
node(:phone_message) do |invitation|
begin
old_formats = formats
self.formats = [:text] # hack so partials resolve with html not json format
view_renderer.render( self, {:template => "invitation_mailer/rsvp_sms", :object => #invitation})
ensure
self.formats = old_formats
end
end
Everything works as expected the first time this code is run, however, I run into problems the second time I run it because it says there is a missing instance variable (which I assume was generated and cached during the first run).
undefined method
_app_views_invitation_mailer_rsvp_sms_text_erb___2510743827238765954_2192068340
for # (ActionView::Template::Error)
Is there a better way to render erb templates into rabl?
You could try using ERB as standalone, and not going through the view renderer, like so:
object #invitation
node(:phone_message) do |invitation|
begin
template = ERB.new(File.read("path/to/template.erb"))
template.result(binding)
end
end
binding is a method on Object (through the Kernel module) and it returns the binding which holds the current context, which also includes instance variables (#invitation in this case)
Update:
Don't really know if this will help you get any further (and I also realised it's been more than a year since you posted this), but here's another way to render ERB templates in a standalone fashion:
view = ActionView::Base.new(ActionController::Base.view_paths, {})
class << view
include ApplicationHelper
include Rails.application.routes.url_helpers
end
Rails.application.routes.default_url_options = ActionMailer::Base.default_url_options
view.render(:file => "path/to/template.html.erb", :locals => {:local_var => 'content'})
When I have time I should actually try this with Rabl.
Related
In my Rails application I'd like to have a special route to download a custom PDF.
This PDF should be generated via PDFKit from an ERB template in my application. Instead of describing what I'd like to achieve, I better paste some non-executable but commented code:
class MyController < ApplicationController
def download_my_list_as_pdf
# The template uses the instance variables below
#user_id = params[:user_id]
#items = ['first_item', 'second_item']
# This line describes what I'd like to do but behaves not like I want ;)
# Render the ERB template and save the rendered html in a variable
# I'd also use another layout
rendered_html = render :download_my_list_as_pdf
kit = PDFKit.new(rendered_html, page_size: 'A4')
kit.to_pdf
pdf_file_path = "#{Rails.root}/public/my_list.pdf"
kit.to_file(pdf_file_path)
send_file pdf_file_path, type: 'application/pdf'
# This is the message I'd like to show at the end
# But using 'render' more than once is not allowed
render plain: 'Download complete'
end
end
I wasn't able to find an answer to this problem yet, any help would be greatly appreciated!
render_to_string(*args, &block)
Raw rendering of a template to a string.
It is similar to render, except that it does not set the response_body
and it should be guaranteed to always return a string.
render does not return a string it sets the response_body of the response.
class MyController < ApplicationController
def download_my_list_as_pdf
# The template uses the instance variables below
#user_id = params[:user_id]
#items = ['first_item', 'second_item']
# This line describes what I'd like to do but behaves not like I want ;)
# Render the ERB template and save the rendered html in a variable
# I'd also use another layout
rendered_html = render_string(:download_my_list_as_pdf)
kit = PDFKit.new(rendered_html, page_size: 'A4')
kit.to_pdf
pdf_file_path = "#{Rails.root}/public/my_list.pdf"
kit.to_file(pdf_file_path)
send_file pdf_file_path, type: 'application/pdf'
end
end
However if you are sending a file you cannot send text or html as well. This is not a limitation of Rails but rather how HTTP works. One request - one response.
Usually javascript is used to create notifications surrounding file downloads. But consider first if its really needed as its pretty annoying to users as the browser usually tells you that you downloaded a file anyways.
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.
In the app I'm working on, I have defined a method task_types in the model:
task.rb
def self.task_types
["ad_hoc"]
end
I use task_types to populate a drop-down menu, but I would also like to use it to dynamically render a partial.
What I have in mind is, for each task type, there will be an associated comment box. I went ahead and made a helper that will call the correct partial depending upon which task type was selected:
#tasks_helper.rb
module TasksHelper
def completion_comment(task)
task_types = #task.task_type
render :partial => "#{Task.task_types}", :locals => {:task => task}
end
end
Unfortunately, when I called completion_comment, I received the error message "The partial name (["ad_hoc"]) is not a valid Ruby identifier."
What I'm looking for is a dynamic way to render the appropriate partial. I think I'm on the right track, but I'm not sure how to extract the array elements from my task_types method (as you can see in the error message, the brackets and quotation marks are getting pulled into the render action). Or, perhaps I need to utilize a different method for dynamically rendering the partial. Any help is appreciated.
Here's what worked:
module TasksHelper
def render_task_form(task)
render :partial => "/tasks/completed/#{task.task_type.downcase}"
end
end
I had tried this solution much earlier, and had received an error that "The partial name (/tasks/completed/) is not a valid Ruby identifier; make sure your partial name starts with a letter or underscore, and is followed by any combinations of letters, numbers, or underscores."
I tried it again, and to remedy this problem I deleted all tasks from the database. Now the partial renders dynamically. Hopefully this helps someone else!
You need a string instead of the entire task_types array. #task.task_type should return a key that a) matches an element in the task types array and b) matches a known partial.
The following is a bit more complicated that it needs to be but should do the trick:
tasks_helper.rb
module TasksHelper
def completion_comment(task)
if Task.task_types.include? task.task_type
render :partial => task.task_type,
:locals => {
:task => task
}
else
# render a generic comment box here
end
end
end
In Rails 4, the view or the partial name is supposed to respond to a valid Ruby identifier.
So, the entire view name must follow the same format as a ruby-identifier:
it should start with a _ or character
it cannot start with a number
it can have only _ and alphanumerics.
So, considering that task_type is a valid ruby identifier (which it should be), it will work. In generate this code will not work in Rails 4
render '/tasks/completed/some-task'
but this will work
render '/tasks/completed/some_task' # note the underscore.
In my controller, i have a method defined as:
def self.store_pdf(id)
...
end
in that method, I need to call render_to_string to render the correct file / layout:
render_to_string(
:action => "../view/current_version/show.pdf.erb",
:layout => false)
but because render_to_string is both an instance method and protected, I need to do the following:
me = self.new # self is the cortroller
me.send(:render_to_string,
:action => "../view/current_version/show.pdf.erb",
:layout => false)
but then there are dependencies such as the response object that render_to_string needs to work, as shown here: http://apidock.com/rails/ActionController/Base/render_to_string
So, I began adding them
me.send(:response=, ActionController::Response.new)
But, more and more of the global instance variables need to be defined, and I decided it was too much work just to try to get one static method to work.
The method needs to be static, so that delayed_job can run the method in the background at a later time.
Anyone have an idea as to how to pull this off?
You can read erb via ERB if you are not using any rails helper,If you are using any rails helper then include Rails helper.
you can refer using here or
require 'erb'
class PdfRender
#include ActionView::Helpers::OutputSafetyHelper
#include helper if any is present any
def self.render_pdf(id)
#set any instance variable if you are using in pdf
content = File.read('path/of/erb/template')
template = ERB.new(content)
# template content will give you text now you can render or generate pdf
template_content = template.result(binding)
end
end
Note:
replace h() with CGI.escapeHTML()
I'm trying to use delayed_job to update a remote database via xml
In my lib folder I put a file with a class that should do a render_to_text with template.xml.builder, but I get:
undefined method `render_to_string' for #<SyncJob:0x7faf4e6c0480>...
What am I doing wrong?
ac = ActionController::Base.new()
ac.render_to_string(:partial => '/path/to/your/template', :locals => {:varable => somevarable})
I had problems with a undefined helper method then I used ApplicationController
ApplicationController.new.render_to_string
render_to_string is defined in ActionController::Base. Since the class/module is defined outside the scope of the Rails controllers the function is not available.
You are going to have to manually render the file. I don't know what you are using for your templates (ERB, Haml, etc.). But you are going to have load the template and parse it yourself.
So if ERB, something like this:
require 'erb'
x = 42
template = ERB.new <<-EOF
The value of x is: <%= x %>
EOF
puts template.result(binding)
You will have to open the template file and send the contents to ERB.new, but that an exercise left for you. Here are the docs for ERB.
That's the general idea.
Rails 5
render_to_string and others are now available as class methods on the controller. So you may do the following with whatever controller you prefer: ApplicationController.render_to_string
I specifically needed to assign a dynamic instance variable for the templates based on an object's class so my example looked like:
ApplicationController.render_to_string(
assigns: { :"#{lowercase_class}" => document_object },
inline: '' # or whatever templates you want to use
)
Great blog post by the developer who made the rails PR: https://evilmartians.com/chronicles/new-feature-in-rails-5-render-views-outside-of-actions
You could turn your template.xml.builder into a partial (_template.xml.builder) and then render it by instantiating an ActionView::Base and calling render
av = ActionView::Base.new(Rails::Configuration.new.view_path)
av.extend ApplicationController.master_helper_module
xml = av.render :partial => 'something/template'
I haven't tried it with xml yet, but it works well with html partials.