middleman/middleman-core/lib/middleman-core/core_extensions/rendering.rb

544 lines
18 KiB
Ruby

# Shutup Tilt Warnings
# @private
class Tilt::Template
def warn(*)
end
end
# Rendering extension
# rubocop:disable UnderscorePrefixedVariableName
module Middleman
module CoreExtensions
module Rendering
# Setup extension
class << self
# Once registered
def registered(app)
# Include methods
app.send :include, InstanceMethods
app.define_hook :before_render
app.define_hook :after_render
::Tilt.mappings.delete('html') # WTF, Tilt?
::Tilt.mappings.delete('csv')
require 'active_support/core_ext/string/output_safety'
# Activate custom renderers
require 'middleman-core/renderers/erb'
app.register Middleman::Renderers::ERb
# CoffeeScript Support
begin
require 'middleman-core/renderers/coffee_script'
app.register Middleman::Renderers::CoffeeScript
rescue LoadError
end
# Haml Support
begin
require 'middleman-core/renderers/haml'
app.register Middleman::Renderers::Haml
rescue LoadError
end
# Sass Support
begin
require 'middleman-core/renderers/sass'
app.register Middleman::Renderers::Sass
rescue LoadError
end
# Markdown Support
require 'middleman-core/renderers/markdown'
app.register Middleman::Renderers::Markdown
# AsciiDoc Support
begin
require 'middleman-core/renderers/asciidoc'
app.register Middleman::Renderers::AsciiDoc
rescue LoadError
end
# Liquid Support
begin
require 'middleman-core/renderers/liquid'
app.register Middleman::Renderers::Liquid
rescue LoadError
end
# Slim Support
begin
require 'middleman-core/renderers/slim'
app.register Middleman::Renderers::Slim
rescue LoadError
end
# Less Support
begin
require 'middleman-core/renderers/less'
app.register Middleman::Renderers::Less
rescue LoadError
end
# Stylus Support
begin
require 'middleman-core/renderers/stylus'
app.register Middleman::Renderers::Stylus
rescue LoadError
end
# Clean up missing Tilt exts
app.after_configuration do
Tilt.mappings.each do |key, _|
begin
Tilt[".#{key}"]
rescue LoadError, NameError
Tilt.mappings.delete(key)
end
end
end
end
alias_method :included, :registered
end
# Custom error class for handling
class TemplateNotFound < RuntimeError
end
# Rendering instance methods
module InstanceMethods
# Add or overwrite a default template extension
#
# @param [Hash] extension_map
# @return [Hash]
def template_extensions(extension_map=nil)
@_template_extensions ||= {}
@_template_extensions.merge!(extension_map) if extension_map
@_template_extensions
end
# Render a template, with layout, given a path
#
# @param [String] path
# @param [Hash] locs
# @param [Hash] opts
# @return [String]
def render_template(path, locs={}, opts={}, blocks=[])
extension = File.extname(path)
engine = extension[1..-1].to_sym
if defined?(::I18n)
old_locale = ::I18n.locale
::I18n.locale = opts[:lang] if opts[:lang]
end
# Use a dup of self as a context so that instance variables set within
# the template don't persist for other templates.
context = dup
blocks.each do |block|
context.instance_eval(&block)
end
# Store current locs/opts for later
@current_locs = locs
@current_opts = opts
content = _render_with_all_renderers(path, locs, context, opts)
# If we need a layout and have a layout, use it
if layout_path = fetch_layout(engine, opts)
content = render_individual_file(layout_path, locs, opts, context) { content }
end
# Return result
content
ensure
# Pop all the saved variables from earlier as we may be returning to a
# previous render (layouts, partials, nested layouts).
::I18n.locale = old_locale if defined?(::I18n)
@content_blocks = nil
@current_locs = nil
@current_opts = nil
end
private
def _render_with_all_renderers(path, locs, context, opts, &block)
# Keep rendering template until we've used up all extensions. This
# handles cases like `style.css.sass.erb`
content = nil
while ::Tilt[path]
begin
opts[:template_body] = content if content
content = if block_given?
render_individual_file(path, locs, opts, context, &block)
else
render_individual_file(path, locs, opts, context)
end
path = File.basename(path, File.extname(path))
rescue LocalJumpError
raise "Tried to render a layout (calls yield) at #{path} like it was a template. Non-default layouts need to be in #{source}/#{config[:layouts_dir]}."
end
end
content
end
public
# Sinatra/Padrino compatible render method signature referenced by some view
# helpers. Especially partials.
#
# @param [String, Symbol] engine
# @param [String, Symbol] data
# @param [Hash] options
# @return [String]
def render(_, data, options={}, &block)
partial_name = data.to_s
found_partial = locate_partial(partial_name, false) || locate_partial(partial_name, true)
# Look in the partials_dir for the partial with the current engine
unless found_partial
partials_path = File.join(config[:partials_dir], partial_name)
found_partial = locate_partial(partials_path, false) || locate_partial(partials_path, true)
end
raise ::Middleman::CoreExtensions::Rendering::TemplateNotFound, "Could not locate partial: #{data}" unless found_partial
locals = options[:locals]
if ::Tilt[found_partial]
# Render the partial if found, otherwise throw exception
_render_with_all_renderers(found_partial, locals, self, options, &block)
else
read_template_file(found_partial)
end
end
def read_template_file(path)
data = ::File.open(path, 'rb') { |io| io.read }
if data.respond_to?(:force_encoding)
# Set it to the default external (without verifying)
data.force_encoding(::Encoding.default_external) if ::Encoding.default_external
end
data
end
# Partial locator.
#
# @param [String] partial_name
# @return [String]
def locate_partial(partial_name, try_static=true)
resolve_opts = { try_without_underscore: true, try_static: try_static }
# If the path is known to the sitemap
if resource = sitemap.find_resource_by_path(current_path)
current_dir = File.dirname(resource.source_file)
resolve_opts[:preferred_engine] = File.extname(resource.source_file)[1..-1].to_sym
# Look for partials relative to the current path
relative_dir = File.join(current_dir.sub(%r{^#{Regexp.escape(source_dir)}/?}, ''), partial_name)
resolve_template(relative_dir, resolve_opts) || resolve_template(partial_name, resolve_opts)
else
resolve_template(partial_name, resolve_opts)
end
end
# Render an on-disk file. Used for everything, including layouts.
#
# @param [String, Symbol] path
# @param [Hash] locs
# @param [Hash] opts
# @param [Class] context
# @return [String]
def render_individual_file(path, locs={}, opts={}, context=self, &block)
path = path.to_s
# Mutability is FUN!
# Try to work around: https://github.com/middleman/middleman/issues/501
locs = locs.dup
# Detect the rendering engine from the extension
extension = File.extname(path)
engine = extension[1..-1].to_sym
# Store last engine for later (could be inside nested renders)
context.current_engine, engine_was = engine, context.current_engine
# Save current buffer for later
@_out_buf, _buf_was = '', @_out_buf
# Read from disk or cache the contents of the file
body = if opts[:template_body]
opts.delete(:template_body)
else
template_data_for_file(path)
end
# Merge per-extension options from config
extension = File.extname(path)
options = opts.dup.merge(options_for_ext(extension))
options[:outvar] ||= '@_out_buf'
options[:default_encoding] ||= 'UTF-8'
options.delete(:layout)
# Overwrite with frontmatter options
options = options.deep_merge(options[:renderer_options]) if options[:renderer_options]
template_class = ::Tilt[path]
# Allow hooks to manipulate the template before render
self.class.callbacks_for_hook(:before_render).each do |callback|
# Uber::Options::Value doesn't respond to call
newbody = if callback.is_a? ::Uber::Options::Value
callback.call(self, body, path, locs, template_class)
elsif callback.respond_to?(:evaluate)
callback.call(body, path, locs, template_class)
end
body = newbody if newbody # Allow the callback to return nil to skip it
end
# Read compiled template from disk or cache
template = cache.fetch(:compiled_template, extension, options, body) do
::Tilt.new(path, 1, options) { body }
end
# Render using Tilt
content = template.render(context || ::Object.new, locs, &block)
# Allow hooks to manipulate the result after render
self.class.callbacks_for_hook(:after_render).each do |callback|
# Uber::Options::Value doesn't respond to call
newcontent = if callback.is_a? ::Uber::Options::Value
callback.call(self, content, path, locs, template_class)
elsif callback.respond_to?(:evaluate)
callback.call(content, path, locs, template_class)
end
content = newcontent if newcontent # Allow the callback to return nil to skip it
end
output = ::ActiveSupport::SafeBuffer.new ''
output.safe_concat content
output
ensure
# Reset stored buffer
@_out_buf = _buf_was
context.current_engine = engine_was
end
# Get the template data from a path
# @param [String] path
# @return [String]
def template_data_for_file(path)
read_template_file(File.expand_path(path, source_dir))
end
# Get a hash of configuration options for a given file extension, from
# config.rb
#
# @param [String] ext
# @return [Hash]
def options_for_ext(ext)
# Read options for extension from config/Tilt or cache
cache.fetch(:options_for_ext, ext) do
options = {}
# Find all the engines which handle this extension in tilt. Look for
# config variables of that name and merge it
extension_class = ::Tilt[ext]
::Tilt.mappings.each do |mapping_ext, engines|
next unless engines.include? extension_class
engine_options = config[mapping_ext.to_sym] || {}
options.merge!(engine_options)
end
options
end
end
# Find a layout for a given engine
#
# @param [Symbol] engine
# @param [Hash] opts
# @return [String]
def fetch_layout(engine, opts)
# The layout name comes from either the system default or the options
local_layout = opts.key?(:layout) ? opts[:layout] : config[:layout]
return false unless local_layout
# Look for engine-specific options
engine_options = respond_to?(engine) ? send(engine) : {}
# The engine for the layout can be set in options, engine_options or passed
# into this method
layout_engine = if opts.key?(:layout_engine)
opts[:layout_engine]
elsif engine_options.key?(:layout_engine)
engine_options[:layout_engine]
else
engine
end
# Automatic mode
if local_layout == :_auto_layout
# Look for :layout of any extension
# If found, use it. If not, continue
locate_layout(:layout, layout_engine) || false
else
# Look for specific layout
# If found, use it. If not, error.
if layout_path = locate_layout(local_layout, layout_engine)
layout_path
else
raise ::Middleman::CoreExtensions::Rendering::TemplateNotFound, "Could not locate layout: #{local_layout}"
end
end
end
# Find a layout on-disk, optionally using a specific engine
# @param [String] name
# @param [Symbol] preferred_engine
# @return [String]
def locate_layout(name, preferred_engine=nil)
resolve_opts = {}
resolve_opts[:preferred_engine] = preferred_engine unless preferred_engine.nil?
# Check layouts folder
layout_path = resolve_template(File.join(config[:layouts_dir], name.to_s), resolve_opts)
# If we didn't find it, check root
layout_path = resolve_template(name, resolve_opts) unless layout_path
# Return the path
layout_path
end
# Allow layouts to be wrapped in the contents of other layouts
# @param [String, Symbol] layout_name
# @return [void]
def wrap_layout(layout_name, &block)
# Save current buffer for later
@_out_buf, _buf_was = '', @_out_buf
layout_path = locate_layout(layout_name, current_engine)
unless layout_path
raise ::Middleman::CoreExtensions::Rendering::TemplateNotFound, "Could not locate layout: #{layout_name}"
end
extension = File.extname(layout_path)
engine = extension[1..-1].to_sym
# Store last engine for later (could be inside nested renders)
self.current_engine = engine
engine_was = current_engine
begin
content = if block_given?
capture_html(&block)
else
''
end
ensure
# Reset stored buffer
@_out_buf = _buf_was
end
concat_safe_content render_individual_file(layout_path, @current_locs || {}, @current_opts || {}, self) { content }
ensure
self.current_engine = engine_was
end
# The currently rendering engine
# @return [Symbol, nil]
def current_engine
@_current_engine ||= nil
end
# The currently rendering engine
# @return [Symbol, nil]
def current_engine=(v)
@_current_engine = v
end
# Find a template on disk given a output path
# @param [String] request_path
# @option options [Boolean] :preferred_engine If set, try this engine first, then fall back to any engine.
# @option options [Boolean] :try_without_underscore
# @option options [Boolean] :try_static
# @return [Array<String, Symbol>, Boolean]
def resolve_template(request_path, options={})
# Find the path by searching or using the cache
request_path = request_path.to_s
cache.fetch(:resolve_template, request_path, options) do
relative_path = Util.strip_leading_slash(request_path)
on_disk_path = File.expand_path(relative_path, source_dir)
preferred_engines = if options[:try_static]
[nil]
else
possible_engines = ['*'] # By default, any engine will do
# If we're specifically looking for a preferred engine
if options.key?(:preferred_engine)
extension_class = ::Tilt[options[:preferred_engine]]
# Get a list of extensions for a preferred engine
matched_exts = ::Tilt.mappings.select do |_, engines|
engines.include? extension_class
end.keys
# Prefer to look for the matched extensions
unless matched_exts.empty?
possible_engines.unshift('{' + matched_exts.join(',') + '}')
end
end
possible_engines
end
search_paths = preferred_engines.flat_map do |preferred_engine|
path_with_ext = on_disk_path.dup
path_with_ext << ('.' + preferred_engine) unless preferred_engine.nil?
paths = [path_with_ext]
if options[:try_without_underscore]
paths << path_with_ext.sub(relative_path, relative_path.sub(/^_/, '').sub(/\/_/, '/'))
end
paths
end
found_path = nil
search_paths.each do |path_with_ext|
found_path = ::Middleman::Util.glob_directory(path_with_ext).find do |path|
::Tilt[path]
end
unless found_path
found_path = path_with_ext if File.exist?(path_with_ext)
end
break if found_path
end
# If we found one, return it
if found_path
found_path
elsif File.exist?(on_disk_path)
on_disk_path
else
false
end
end
end
end
end
end
end