Action View Template

Namespace
Methods
E
I
L
N
R
S
T
Attributes
[RW] formats
[R] handler
[R] identifier
[RW] locals
[R] original_encoding
[R] source
[R] updated_at
[RW] variants
[RW] virtual_path
Class Public methods
new(source, identifier, handler, details)
# File actionview/lib/action_view/template.rb, line 128
def initialize(source, identifier, handler, details)
  format = details[:format] || (handler.default_format if handler.respond_to?(:default_format))

  @source            = source
  @identifier        = identifier
  @handler           = handler
  @compiled          = false
  @original_encoding = nil
  @locals            = details[:locals] || []
  @virtual_path      = details[:virtual_path]
  @updated_at        = details[:updated_at] || Time.now
  @formats           = Array(format).map { |f| f.respond_to?(:ref) ? f.ref : f  }
  @variants          = [details[: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 202
def encode!
  return 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 188
def inspect
  @inspect ||= defined?(Rails.root) ? identifier.sub("#{Rails.root}/", "".freeze) : identifier
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 104
eager_autoload do
  autoload :Error
  autoload :Handlers
  autoload :HTML
  autoload :Text
  autoload :Types
end
refresh(view)

Receives a view object and return a template similar to self by using @virtual_path.

This method is useful if you have a template object but it does not contain its source anymore since it was already compiled. In such cases, all you need to do is to call refresh passing in the view object.

Notice this method raises an error if the template to be refreshed does not have a virtual path set (true just for inline templates).

# File actionview/lib/action_view/template.rb, line 177
def refresh(view)
  raise "A template needs to have a virtual path in order to be refreshed" unless @virtual_path
  lookup  = view.lookup_context
  pieces  = @virtual_path.split("/")
  name    = pieces.pop
  partial = !!name.sub!(/^_/, "")
  lookup.disable_cache do
    lookup.find_template(name, [ pieces.join("/") ], partial, @locals)
  end
end
render(view, locals, buffer = nil, &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 156
def render(view, locals, buffer = nil, &block)
  instrument_render_template do
    compile!(view)
    view.send(method_name, locals, buffer, &block)
  end
rescue => e
  handle_render_error(view, e)
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 146
def supports_streaming?
  handler.respond_to?(:supports_streaming?) && handler.supports_streaming?
end
type()
# File actionview/lib/action_view/template.rb, line 165
def type
  @type ||= Types[@formats.first] if @formats.first
end
Instance Private methods
instrument(action, &block)
# File actionview/lib/action_view/template.rb, line 349
def instrument(action, &block) # :doc:
  ActiveSupport::Notifications.instrument("#{action}.action_view", instrument_payload, &block)
end