Integrated Yehuda's new callback code from rails

This commit is contained in:
Peter Gumeson 2009-06-07 02:57:22 -07:00
parent 1c6e073b47
commit dc4787e905
8 changed files with 228 additions and 221 deletions

View file

@ -1,8 +1,8 @@
require File.join(File.dirname(__FILE__), '..', 'support', 'class')
# Extracted from ActiveSupport::Callbacks written by Yehuda Katz
# http://github.com/wycats/rails/raw/abstract_controller/activesupport/lib/active_support/new_callbacks.rb
# http://github.com/wycats/rails/raw/18b405f154868204a8f332888871041a7bad95e1/activesupport/lib/active_support/callbacks.rb
# Extracted from ActiveSupport::NewCallbacks written by Yehuda Katz
# http://github.com/rails/rails/raw/d6e4113c83a9d55be6f2af247da2cecaa855f43b/activesupport/lib/active_support/new_callbacks.rb
# http://github.com/rails/rails/commit/1126a85aed576402d978e6f76eb393b6baaa9541
module CouchRest
# Callbacks are hooks into the lifecycle of an object that allow you to trigger logic
@ -85,19 +85,18 @@ module CouchRest
def self.included(klass)
klass.extend ClassMethods
end
def run_callbacks(kind, options = {}, &blk)
send("_run_#{kind}_callbacks", &blk)
end
class Callback
@@_callback_sequence = 0
attr_accessor :filter, :kind, :name, :options, :per_key, :klass
def initialize(filter, kind, options, klass, name)
def initialize(filter, kind, options, klass)
@kind, @klass = kind, klass
@name = name
normalize_options!(options)
@per_key = options.delete(:per_key)
@ -108,7 +107,7 @@ module CouchRest
_compile_per_key_options
end
def clone(klass)
obj = super()
obj.klass = klass
@ -120,7 +119,7 @@ module CouchRest
obj.options[:unless] = @options[:unless].dup
obj
end
def normalize_options!(options)
options[:if] = Array(options[:if])
options[:unless] = Array(options[:unless])
@ -129,14 +128,13 @@ module CouchRest
options[:per_key][:if] = Array(options[:per_key][:if])
options[:per_key][:unless] = Array(options[:per_key][:unless])
end
def next_id
@@_callback_sequence += 1
end
def matches?(_kind, _name, _filter)
def matches?(_kind, _filter)
@kind == _kind &&
@name == _name &&
@filter == _filter
end
@ -144,11 +142,11 @@ module CouchRest
filter_options[:if].push(new_options[:unless]) if new_options.key?(:unless)
filter_options[:unless].push(new_options[:if]) if new_options.key?(:if)
end
def recompile!(_options, _per_key)
_update_filter(self.options, _options)
_update_filter(self.per_key, _per_key)
@callback_id = next_id
@filter = _compile_filter(@raw_filter)
@compiled_options = _compile_options(@options)
@ -164,19 +162,19 @@ module CouchRest
end
RUBY_EVAL
end
# This will supply contents for before and around filters, and no
# contents for after filters (for the forward pass).
def start(key = nil, options = {})
object, terminator = (options || {}).values_at(:object, :terminator)
return if key && !object.send("_one_time_conditions_valid_#{@callback_id}?")
terminator ||= false
# options[0] is the compiled form of supplied conditions
# options[1] is the "end" for the conditional
if @kind == :before || @kind == :around
if @kind == :before
# if condition # before_save :filter_name, :if => :condition
@ -204,7 +202,7 @@ module CouchRest
# yield self
# end
# end
name = "_conditional_callback_#{@kind}_#{next_id}"
txt = <<-RUBY_EVAL
def #{name}(halted)
@ -222,14 +220,14 @@ module CouchRest
end
end
end
# This will supply contents for around and after filters, but not
# before filters (for the backward pass).
def end(key = nil, options = {})
object = (options || {})[:object]
return if key && !object.send("_one_time_conditions_valid_#{@callback_id}?")
if @kind == :around || @kind == :after
# if condition # after_save :filter_name, :if => :condition
# filter_name
@ -241,27 +239,27 @@ module CouchRest
end
end
end
private
# Options support the same options as filters themselves (and support
# symbols, string, procs, and objects), so compile a conditional
# expression based on the options
def _compile_options(options)
return [] if options[:if].empty? && options[:unless].empty?
conditions = []
unless options[:if].empty?
conditions << Array(_compile_filter(options[:if]))
end
unless options[:unless].empty?
conditions << Array(_compile_filter(options[:unless])).map {|f| "!#{f}"}
end
["if #{conditions.flatten.join(" && ")}", "end"]
end
# Filters support:
# Arrays:: Used in conditions. This is used to specify
# multiple conditions. Used internally to
@ -289,7 +287,22 @@ module CouchRest
filter
when Proc
@klass.send(:define_method, method_name, &filter)
method_name << (filter.arity == 1 ? "(self)" : "")
method_name << case filter.arity
when 1
"(self)"
when 2
" self, Proc.new "
else
""
end
when Method
@klass.send(:define_method, "#{method_name}_method") { filter }
@klass.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
def #{method_name}(&blk)
#{method_name}_method.call(self, &blk)
end
RUBY_EVAL
method_name
when String
@klass.class_eval <<-RUBY_EVAL
def #{method_name}
@ -298,52 +311,65 @@ module CouchRest
RUBY_EVAL
method_name
else
kind, name = @kind, @name
@klass.send(:define_method, method_name) do
filter.send("#{kind}_#{name}", self)
end
kind = @kind
@klass.send(:define_method, "#{method_name}_object") { filter }
_normalize_legacy_filter(kind, filter)
@klass.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
def #{method_name}(&blk)
#{method_name}_object.send(:#{kind}, self, &blk)
end
RUBY_EVAL
method_name
end
end
def _normalize_legacy_filter(kind, filter)
if !filter.respond_to?(kind) && filter.respond_to?(:filter)
filter.metaclass.class_eval(
"def #{kind}(context, &block) filter(context, &block) end",
__FILE__, __LINE__ - 1)
elsif filter.respond_to?(:before) && filter.respond_to?(:after) && kind == :around
def filter.around(context)
should_continue = before(context)
yield if should_continue
after(context)
end
end
end
end
# This method_missing is supplied to catch callbacks with keys and create
# the appropriate callback for future use.
def method_missing(meth, *args, &blk)
if meth.to_s =~ /_run__([\w:]+)__(\w+)__(\w+)__callbacks/
return self.class._create_and_run_keyed_callback($1, $2.to_sym, $3.to_sym, self, &blk)
end
super
end
# An Array with a compile method
class CallbackChain < Array
def initialize(symbol)
@symbol = symbol
end
def compile(key = nil, options = {})
method = []
method << "halted = false"
each do |callback|
method << callback.start(key, options)
end
method << "yield self if block_given?"
method << "yield self if block_given? && !halted"
reverse_each do |callback|
method << callback.end(key, options)
end
method.compact.join("\n")
end
def clone(klass)
chain = CallbackChain.new(@symbol)
chain.push(*map {|c| c.clone(klass)})
end
end
module ClassMethods
CHAINS = {:before => :before, :around => :before, :after => :after} unless self.const_defined?("CHAINS")
CHAINS = {:before => :before, :around => :before, :after => :after}
# Make the _run_save_callbacks method. The generated method takes
# a block that it'll yield to. It'll call the before and around filters
# in order, yield the block, and then run the after filters.
@ -355,43 +381,44 @@ module CouchRest
# The _run_save_callbacks method can optionally take a key, which
# will be used to compile an optimized callback method for each
# key. See #define_callbacks for more information.
def _define_runner(symbol, str, options)
str = <<-RUBY_EVAL
def _run_#{symbol}_callbacks(key = nil)
def _define_runner(symbol, callbacks)
body = callbacks.compile(nil, :terminator => send("_#{symbol}_terminator"))
body, line = <<-RUBY_EVAL, __LINE__
def _run_#{symbol}_callbacks(key = nil, &blk)
if key
send("_run__\#{self.class.name.split("::").last}__#{symbol}__\#{key}__callbacks") { yield if block_given? }
name = "_run__\#{self.class.name.hash.abs}__#{symbol}__\#{key.hash.abs}__callbacks"
unless respond_to?(name)
self.class._create_keyed_callback(name, :#{symbol}, self, &blk)
end
send(name, &blk)
else
#{str}
#{body}
end
end
RUBY_EVAL
class_eval str, __FILE__, __LINE__ + 1
before_name, around_name, after_name =
options.values_at(:before, :after, :around)
undef_method "_run_#{symbol}_callbacks" if method_defined?("_run_#{symbol}_callbacks")
class_eval body, __FILE__, line
end
# This is called the first time a callback is called with a particular
# key. It creates a new callback method for the key, calculating
# which callbacks can be omitted because of per_key conditions.
def _create_and_run_keyed_callback(klass, kind, key, obj, &blk)
def _create_keyed_callback(name, kind, obj, &blk)
@_keyed_callbacks ||= {}
@_keyed_callbacks[[kind, key]] ||= begin
str = self.send("_#{kind}_callbacks").compile(key, :object => obj, :terminator => self.send("_#{kind}_terminator"))
@_keyed_callbacks[name] ||= begin
str = send("_#{kind}_callbacks").
compile(name, :object => obj, :terminator => send("_#{kind}_terminator"))
class_eval "def #{name}() #{str} end", __FILE__, __LINE__
self.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
def _run__#{klass.split("::").last}__#{kind}__#{key}__callbacks
#{str}
end
RUBY_EVAL
true
end
obj.send("_run__#{klass.split("::").last}__#{kind}__#{key}__callbacks", &blk)
end
# Define callbacks.
#
# Creates a <name>_callback method that you can use to add callbacks.
@ -423,58 +450,62 @@ module CouchRest
# In that case, each action_name would get its own compiled callback
# method that took into consideration the per_key conditions. This
# is a speed improvement for ActionPack.
def update_callbacks(name, filters = CallbackChain.new(name), block = nil)
type = [:before, :after, :around].include?(filters.first) ? filters.shift : :before
options = filters.last.is_a?(Hash) ? filters.pop : {}
filters.unshift(block) if block
responded = self.respond_to?(":_#{name}_callbacks")
callbacks = send("_#{name}_callbacks")
yield callbacks, type, filters, options if block_given?
_define_runner(name, callbacks)
end
def set_callback(name, *filters, &block)
update_callbacks(name, filters, block) do |callbacks, type, filters, options|
filters.map! do |filter|
# overrides parent class
callbacks.delete_if {|c| c.matches?(type, filter) }
Callback.new(filter, type, options.dup, self)
end
options[:prepend] ? callbacks.unshift(*filters) : callbacks.push(*filters)
end
end
def skip_callback(name, *filters, &block)
update_callbacks(name, filters, block) do |callbacks, type, filters, options|
filters.each do |filter|
callbacks = send("_#{name}_callbacks=", callbacks.clone(self))
filter = callbacks.find {|c| c.matches?(type, filter) }
if filter && options.any?
filter.recompile!(options, options[:per_key] || {})
else
callbacks.delete(filter)
end
end
end
end
def define_callbacks(*symbols)
terminator = symbols.pop if symbols.last.is_a?(String)
symbols.each do |symbol|
self.extlib_inheritable_accessor("_#{symbol}_terminator")
self.send("_#{symbol}_terminator=", terminator)
self.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
extlib_inheritable_accessor :_#{symbol}_callbacks
self._#{symbol}_callbacks = CallbackChain.new(:#{symbol})
extlib_inheritable_accessor("_#{symbol}_terminator") { terminator }
def self.#{symbol}_callback(*filters, &blk)
type = [:before, :after, :around].include?(filters.first) ? filters.shift : :before
options = filters.last.is_a?(Hash) ? filters.pop : {}
filters.unshift(blk) if block_given?
filters.map! do |filter|
# overrides parent class
self._#{symbol}_callbacks.delete_if {|c| c.matches?(type, :#{symbol}, filter)}
Callback.new(filter, type, options.dup, self, :#{symbol})
end
self._#{symbol}_callbacks.push(*filters)
_define_runner(:#{symbol},
self._#{symbol}_callbacks.compile(nil, :terminator => _#{symbol}_terminator),
options)
end
def self.skip_#{symbol}_callback(*filters, &blk)
type = [:before, :after, :around].include?(filters.first) ? filters.shift : :before
options = filters.last.is_a?(Hash) ? filters.pop : {}
filters.unshift(blk) if block_given?
filters.each do |filter|
self._#{symbol}_callbacks = self._#{symbol}_callbacks.clone(self)
filter = self._#{symbol}_callbacks.find {|c| c.matches?(type, :#{symbol}, filter) }
per_key = options[:per_key] || {}
if filter
filter.recompile!(options, per_key)
else
self._#{symbol}_callbacks.delete(filter)
end
_define_runner(:#{symbol},
self._#{symbol}_callbacks.compile(nil, :terminator => _#{symbol}_terminator),
options)
end
end
extlib_inheritable_accessor("_#{symbol}_callbacks") do
CallbackChain.new(symbol)
end
self.class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
def self.reset_#{symbol}_callbacks
self._#{symbol}_callbacks = CallbackChain.new(:#{symbol})
_define_runner(:#{symbol}, self._#{symbol}_callbacks.compile, {})
update_callbacks(:#{symbol})
end
self.#{symbol}_callback(:before)
self.set_callback(:#{symbol}, :before)
RUBY_EVAL
end
end