# frozen_string_literal: true require "active_support/core_ext/module/attr_internal" require "active_support/core_ext/module/attribute_accessors" require "active_support/ordered_options" require "active_support/deprecation" require "action_view/log_subscriber" require "action_view/helpers" require "action_view/context" require "action_view/template" require "action_view/lookup_context" module ActionView #:nodoc: # = Action View Base # # Action View templates can be written in several ways. # If the template file has a .erb extension, then it uses the erubi[https://rubygems.org/gems/erubi] # template system which can embed Ruby into an HTML document. # If the template file has a .builder extension, then Jim Weirich's Builder::XmlMarkup library is used. # # == ERB # # You trigger ERB by using embeddings such as <% %>, <% -%>, and <%= %>. The <%= %> tag set is used when you want output. Consider the # following loop for names: # # Names of all the people # <% @people.each do |person| %> # Name: <%= person.name %>
# <% end %> # # The loop is setup in regular embedding tags <% %>, and the name is written using the output embedding tag <%= %>. Note that this # is not just a usage suggestion. Regular output functions like print or puts won't work with ERB templates. So this would be wrong: # # <%# WRONG %> # Hi, Mr. <% puts "Frodo" %> # # If you absolutely must write from within a function use +concat+. # # When on a line that only contains whitespaces except for the tag, <% %> suppresses leading and trailing whitespace, # including the trailing newline. <% %> and <%- -%> are the same. # Note however that <%= %> and <%= -%> are different: only the latter removes trailing whitespaces. # # === Using sub templates # # Using sub templates allows you to sidestep tedious replication and extract common display structures in shared templates. The # classic example is the use of a header and footer (even though the Action Pack-way would be to use Layouts): # # <%= render "shared/header" %> # Something really specific and terrific # <%= render "shared/footer" %> # # As you see, we use the output embeddings for the render methods. The render call itself will just return a string holding the # result of the rendering. The output embedding writes it to the current template. # # But you don't have to restrict yourself to static includes. Templates can share variables amongst themselves by using instance # variables defined using the regular embedding tags. Like this: # # <% @page_title = "A Wonderful Hello" %> # <%= render "shared/header" %> # # Now the header can pick up on the @page_title variable and use it for outputting a title tag: # # <%= @page_title %> # # === Passing local variables to sub templates # # You can pass local variables to sub templates by using a hash with the variable names as keys and the objects as values: # # <%= render "shared/header", { headline: "Welcome", person: person } %> # # These can now be accessed in shared/header with: # # Headline: <%= headline %> # First name: <%= person.first_name %> # # The local variables passed to sub templates can be accessed as a hash using the local_assigns hash. This lets you access the # variables as: # # Headline: <%= local_assigns[:headline] %> # # This is useful in cases where you aren't sure if the local variable has been assigned. Alternatively, you could also use # defined? headline to first check if the variable has been assigned before using it. # # === Template caching # # By default, Rails will compile each template to a method in order to render it. When you alter a template, # Rails will check the file's modification time and recompile it in development mode. # # == Builder # # Builder templates are a more programmatic alternative to ERB. They are especially useful for generating XML content. An XmlMarkup object # named +xml+ is automatically made available to templates with a .builder extension. # # Here are some basic examples: # # xml.em("emphasized") # => emphasized # xml.em { xml.b("emph & bold") } # => emph & bold # xml.a("A Link", "href" => "http://onestepback.org") # => A Link # xml.target("name" => "compile", "option" => "fast") # => # # NOTE: order of attributes is not specified. # # Any method with a block will be treated as an XML markup tag with nested markup in the block. For example, the following: # # xml.div do # xml.h1(@person.name) # xml.p(@person.bio) # end # # would produce something like: # #
#

David Heinemeier Hansson

#

A product of Danish Design during the Winter of '79...

#
# # Here is a full-length RSS example actually used on Basecamp: # # xml.rss("version" => "2.0", "xmlns:dc" => "http://purl.org/dc/elements/1.1/") do # xml.channel do # xml.title(@feed_title) # xml.link(@url) # xml.description "Basecamp: Recent items" # xml.language "en-us" # xml.ttl "40" # # @recent_items.each do |item| # xml.item do # xml.title(item_title(item)) # xml.description(item_description(item)) if item_description(item) # xml.pubDate(item_pubDate(item)) # xml.guid(@person.firm.account.url + @recent_items.url(item)) # xml.link(@person.firm.account.url + @recent_items.url(item)) # # xml.tag!("dc:creator", item.author_name) if item_has_creator?(item) # end # end # end # end # # For more information on Builder please consult the {source # code}[https://github.com/jimweirich/builder]. class Base include Helpers, ::ERB::Util, Context # Specify the proc used to decorate input tags that refer to attributes with errors. cattr_accessor :field_error_proc, default: Proc.new { |html_tag, instance| "
#{html_tag}
".html_safe } # How to complete the streaming when an exception occurs. # This is our best guess: first try to close the attribute, then the tag. cattr_accessor :streaming_completion_on_exception, default: %(">) # Specify whether rendering within namespaced controllers should prefix # the partial paths for ActiveModel objects with the namespace. # (e.g., an Admin::PostsController would render @post using /admin/posts/_post.erb) cattr_accessor :prefix_partial_path_with_controller_namespace, default: true # Specify default_formats that can be rendered. cattr_accessor :default_formats # Specify whether an error should be raised for missing translations cattr_accessor :raise_on_missing_translations, default: false # Specify whether submit_tag should automatically disable on click cattr_accessor :automatically_disable_submit_tag, default: true class_attribute :_routes class_attribute :logger class << self delegate :erb_trim_mode=, to: "ActionView::Template::Handlers::ERB" def cache_template_loading ActionView::Resolver.caching? end def cache_template_loading=(value) ActionView::Resolver.caching = value end def xss_safe? #:nodoc: true end def with_empty_template_cache # :nodoc: subclass = Class.new(self) { # We can't implement these as self.class because subclasses will # share the same template cache as superclasses, so "changed?" won't work # correctly. define_method(:compiled_method_container) { subclass } define_singleton_method(:compiled_method_container) { subclass } } end def changed?(other) # :nodoc: compiled_method_container != other.compiled_method_container end end attr_reader :view_renderer, :lookup_context attr_internal :config, :assigns delegate :formats, :formats=, :locale, :locale=, :view_paths, :view_paths=, to: :lookup_context def assign(new_assigns) # :nodoc: @_assigns = new_assigns.each { |key, value| instance_variable_set("@#{key}", value) } end # :stopdoc: def self.build_lookup_context(context) case context when ActionView::Renderer context.lookup_context when Array ActionView::LookupContext.new(context) when ActionView::PathSet ActionView::LookupContext.new(context) when nil ActionView::LookupContext.new([]) else raise NotImplementedError, context.class.name end end def self.empty with_view_paths([]) end def self.with_view_paths(view_paths, assigns = {}, controller = nil) with_context ActionView::LookupContext.new(view_paths), assigns, controller end def self.with_context(context, assigns = {}, controller = nil) new context, assigns, controller end NULL = Object.new # :startdoc: def initialize(lookup_context = nil, assigns = {}, controller = nil, formats = NULL) #:nodoc: @_config = ActiveSupport::InheritableOptions.new unless formats == NULL ActiveSupport::Deprecation.warn <<~eowarn Passing formats to ActionView::Base.new is deprecated eowarn end case lookup_context when ActionView::LookupContext @lookup_context = lookup_context else ActiveSupport::Deprecation.warn <<~eowarn ActionView::Base instances should be constructed with a lookup context, assignments, and a controller. eowarn @lookup_context = self.class.build_lookup_context(lookup_context) end @view_renderer = ActionView::Renderer.new @lookup_context @current_template = nil @cache_hit = {} assign(assigns) assign_controller(controller) _prepare_context end def run(method, template, locals, buffer, &block) _old_output_buffer, _old_virtual_path, _old_template = @output_buffer, @virtual_path, @current_template @current_template = template @output_buffer = buffer send(method, locals, buffer, &block) ensure @output_buffer, @virtual_path, @current_template = _old_output_buffer, _old_virtual_path, _old_template end def compiled_method_container if self.class == ActionView::Base ActiveSupport::Deprecation.warn <<~eowarn ActionView::Base instances must implement `compiled_method_container` or use the class method `with_empty_template_cache` for constructing an ActionView::Base instances that has an empty cache. eowarn end self.class end def in_rendering_context(options) old_view_renderer = @view_renderer old_lookup_context = @lookup_context if !lookup_context.html_fallback_for_js && options[:formats] formats = Array(options[:formats]) if formats == [:js] formats << :html end @lookup_context = lookup_context.with_prepended_formats(formats) @view_renderer = ActionView::Renderer.new @lookup_context end yield @view_renderer ensure @view_renderer = old_view_renderer @lookup_context = old_lookup_context end ActiveSupport.run_load_hooks(:action_view, self) end end