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Action View Template

Action View Renderable Template for objects that respond to render_in

Namespace
Methods
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Attributes

[R] format
[RW] frozen_string_literal
[R] handler
[R] identifier
[R] locals
[R] variable
[R] variant
[R] virtual_path

Class Public methods

new(source, identifier, handler, locals:, format: nil, variant: nil, virtual_path: nil)

# File actionview/lib/action_view/template.rb, line 123
def initialize(source, identifier, handler, locals:, format: nil, variant: nil, virtual_path: nil)
  @source            = source
  @identifier        = identifier
  @handler           = handler
  @compiled          = false
  @locals            = locals
  @virtual_path      = virtual_path

  @variable = if @virtual_path
    base = @virtual_path.end_with?("/") ? "" : ::File.basename(@virtual_path)
    base =~ /\A_?(.*?)(?:\.\w+)*\z/
    $1.to_sym
  end

  @format            = format
  @variant           = variant
  @compile_mutex     = Mutex.new
end

Instance Public methods

encode!()

This method is responsible for properly setting the encoding of the source. Until this point, we assume that the source is BINARY data. If no additional information is supplied, we assume the encoding is the same as Encoding.default_external.

The user can also specify the encoding via a comment on the first line of the template (# encoding: NAME-OF-ENCODING). This will work with any template engine, as we process out the encoding comment before passing the source on to the template engine, leaving a blank line in its stead.

# File actionview/lib/action_view/template.rb, line 189
def encode!
  source = self.source

  return source unless source.encoding == Encoding::BINARY

  # Look for # encoding: *. If we find one, we'll encode the
  # String in that encoding, otherwise, we'll use the
  # default external encoding.
  if source.sub!(/\A#{ENCODING_FLAG}/, "")
    encoding = magic_encoding = $1
  else
    encoding = Encoding.default_external
  end

  # Tag the source with the default external encoding
  # or the encoding specified in the file
  source.force_encoding(encoding)

  # If the user didn't specify an encoding, and the handler
  # handles encodings, we simply pass the String as is to
  # the handler (with the default_external tag)
  if !magic_encoding && @handler.respond_to?(:handles_encoding?) && @handler.handles_encoding?
    source
  # Otherwise, if the String is valid in the encoding,
  # encode immediately to default_internal. This means
  # that if a handler doesn't handle encodings, it will
  # always get Strings in the default_internal
  elsif source.valid_encoding?
    source.encode!
  # Otherwise, since the String is invalid in the encoding
  # specified, raise an exception
  else
    raise WrongEncodingError.new(source, encoding)
  end
end

inspect()

# File actionview/lib/action_view/template.rb, line 171
def inspect
  "#<#{self.class.name} #{short_identifier} locals=#{@locals.inspect}>"
end

local_assigns

Returns a hash with the defined local variables.

Given this sub template rendering:

<%= render "shared/header", { headline: "Welcome", person: person } %>

You can use local_assigns in the sub templates to access the local variables:

local_assigns[:headline] # => "Welcome"
# File actionview/lib/action_view/template.rb, line 103
eager_autoload do
  autoload :Error
  autoload :RawFile
  autoload :Renderable
  autoload :Handlers
  autoload :HTML
  autoload :Inline
  autoload :Sources
  autoload :Text
  autoload :Types
end

render(view, locals, buffer = ActionView::OutputBuffer.new, add_to_stack: true, &block)

Render a template. If the template was not compiled yet, it is done exactly before rendering.

This method is instrumented as “!render_template.action_view”. Notice that we use a bang in this instrumentation because you don't want to consume this in production. This is only slow if it's being listened to.

# File actionview/lib/action_view/template.rb, line 154
def render(view, locals, buffer = ActionView::OutputBuffer.new, add_to_stack: true, &block)
  instrument_render_template do
    compile!(view)
    view._run(method_name, self, locals, buffer, add_to_stack: add_to_stack, &block)
  end
rescue => e
  handle_render_error(view, e)
end

short_identifier()

# File actionview/lib/action_view/template.rb, line 167
def short_identifier
  @short_identifier ||= defined?(Rails.root) ? identifier.delete_prefix("#{Rails.root}/") : identifier
end

source()

# File actionview/lib/action_view/template.rb, line 175
def source
  @source.to_s
end

supports_streaming?()

Returns whether the underlying handler supports streaming. If so, a streaming buffer may be passed when it starts rendering.

# File actionview/lib/action_view/template.rb, line 144
def supports_streaming?
  handler.respond_to?(:supports_streaming?) && handler.supports_streaming?
end

type()

# File actionview/lib/action_view/template.rb, line 163
def type
  @type ||= Types[format]
end

Instance Private methods

instrument(action, &block)

# File actionview/lib/action_view/template.rb, line 356
def instrument(action, &block) # :doc:
  ActiveSupport::Notifications.instrument("#{action}.action_view", instrument_payload, &block)
end