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author | yugui <yugui@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2008-08-25 15:02:05 +0000 |
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committer | yugui <yugui@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2008-08-25 15:02:05 +0000 |
commit | 0dc342de848a642ecce8db697b8fecd83a63e117 (patch) | |
tree | 2b7ed4724aff1f86073e4740134bda9c4aac1a39 /trunk/lib/yaml.rb | |
parent | ef70cf7138ab8034b5b806f466e4b484b24f0f88 (diff) |
added tag v1_9_0_4
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/tags/v1_9_0_4@18845 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'trunk/lib/yaml.rb')
-rw-r--r-- | trunk/lib/yaml.rb | 440 |
1 files changed, 440 insertions, 0 deletions
diff --git a/trunk/lib/yaml.rb b/trunk/lib/yaml.rb new file mode 100644 index 0000000000..a8da42a321 --- /dev/null +++ b/trunk/lib/yaml.rb @@ -0,0 +1,440 @@ +# -*- mode: ruby; ruby-indent-level: 4; tab-width: 4 -*- vim: sw=4 ts=4 +# $Id$ +# +# = yaml.rb: top-level module with methods for loading and parsing YAML documents +# +# Author:: why the lucky stiff +# + +require 'stringio' +require 'yaml/error' +require 'yaml/syck' +require 'yaml/tag' +require 'yaml/stream' +require 'yaml/constants' + +# == YAML +# +# YAML(tm) (rhymes with 'camel') is a +# straightforward machine parsable data serialization format designed for +# human readability and interaction with scripting languages such as Perl +# and Python. YAML is optimized for data serialization, formatted +# dumping, configuration files, log files, Internet messaging and +# filtering. This specification describes the YAML information model and +# serialization format. Together with the Unicode standard for characters, it +# provides all the information necessary to understand YAML Version 1.0 +# and construct computer programs to process it. +# +# See http://yaml.org/ for more information. For a quick tutorial, please +# visit YAML In Five Minutes (http://yaml.kwiki.org/?YamlInFiveMinutes). +# +# == About This Library +# +# The YAML 1.0 specification outlines four stages of YAML loading and dumping. +# This library honors all four of those stages, although data is really only +# available to you in three stages. +# +# The four stages are: native, representation, serialization, and presentation. +# +# The native stage refers to data which has been loaded completely into Ruby's +# own types. (See +YAML::load+.) +# +# The representation stage means data which has been composed into +# +YAML::BaseNode+ objects. In this stage, the document is available as a +# tree of node objects. You can perform YPath queries and transformations +# at this level. (See +YAML::parse+.) +# +# The serialization stage happens inside the parser. The YAML parser used in +# Ruby is called Syck. Serialized nodes are available in the extension as +# SyckNode structs. +# +# The presentation stage is the YAML document itself. This is accessible +# to you as a string. (See +YAML::dump+.) +# +# For more information about the various information models, see Chapter +# 3 of the YAML 1.0 Specification (http://yaml.org/spec/#id2491269). +# +# The YAML module provides quick access to the most common loading (YAML::load) +# and dumping (YAML::dump) tasks. This module also provides an API for registering +# global types (YAML::add_domain_type). +# +# == Example +# +# A simple round-trip (load and dump) of an object. +# +# require "yaml" +# +# test_obj = ["dogs", "cats", "badgers"] +# +# yaml_obj = YAML::dump( test_obj ) +# # -> --- +# - dogs +# - cats +# - badgers +# ruby_obj = YAML::load( yaml_obj ) +# # => ["dogs", "cats", "badgers"] +# ruby_obj == test_obj +# # => true +# +# To register your custom types with the global resolver, use +add_domain_type+. +# +# YAML::add_domain_type( "your-site.com,2004", "widget" ) do |type, val| +# Widget.new( val ) +# end +# +module YAML + + Resolver = YAML::Syck::Resolver + DefaultResolver = YAML::Syck::DefaultResolver + DefaultResolver.use_types_at( @@tagged_classes ) + GenericResolver = YAML::Syck::GenericResolver + Parser = YAML::Syck::Parser + Emitter = YAML::Syck::Emitter + + # Returns a new default parser + def YAML.parser; Parser.new.set_resolver( YAML.resolver ); end + # Returns a new generic parser + def YAML.generic_parser; Parser.new.set_resolver( GenericResolver ); end + # Returns the default resolver + def YAML.resolver; DefaultResolver; end + # Returns a new default emitter + def YAML.emitter; Emitter.new.set_resolver( YAML.resolver ); end + + # + # Converts _obj_ to YAML and writes the YAML result to _io_. + # + # File.open( 'animals.yaml', 'w' ) do |out| + # YAML.dump( ['badger', 'elephant', 'tiger'], out ) + # end + # + # If no _io_ is provided, a string containing the dumped YAML + # is returned. + # + # YAML.dump( :locked ) + # #=> "--- :locked" + # + def YAML.dump( obj, io = nil ) + obj.to_yaml( io || io2 = StringIO.new ) + io || ( io2.rewind; io2.read ) + end + + # + # Load a document from the current _io_ stream. + # + # File.open( 'animals.yaml' ) { |yf| YAML::load( yf ) } + # #=> ['badger', 'elephant', 'tiger'] + # + # Can also load from a string. + # + # YAML.load( "--- :locked" ) + # #=> :locked + # + def YAML.load( io ) + yp = parser.load( io ) + end + + # + # Load a document from the file located at _filepath_. + # + # YAML.load_file( 'animals.yaml' ) + # #=> ['badger', 'elephant', 'tiger'] + # + def YAML.load_file( filepath ) + File.open( filepath ) do |f| + load( f ) + end + end + + # + # Parse the first document from the current _io_ stream + # + # File.open( 'animals.yaml' ) { |yf| YAML::load( yf ) } + # #=> #<YAML::Syck::Node:0x82ccce0 + # @kind=:seq, + # @value= + # [#<YAML::Syck::Node:0x82ccd94 + # @kind=:scalar, + # @type_id="str", + # @value="badger">, + # #<YAML::Syck::Node:0x82ccd58 + # @kind=:scalar, + # @type_id="str", + # @value="elephant">, + # #<YAML::Syck::Node:0x82ccd1c + # @kind=:scalar, + # @type_id="str", + # @value="tiger">]> + # + # Can also load from a string. + # + # YAML.parse( "--- :locked" ) + # #=> #<YAML::Syck::Node:0x82edddc + # @type_id="tag:ruby.yaml.org,2002:sym", + # @value=":locked", @kind=:scalar> + # + def YAML.parse( io ) + yp = generic_parser.load( io ) + end + + # + # Parse a document from the file located at _filepath_. + # + # YAML.parse_file( 'animals.yaml' ) + # #=> #<YAML::Syck::Node:0x82ccce0 + # @kind=:seq, + # @value= + # [#<YAML::Syck::Node:0x82ccd94 + # @kind=:scalar, + # @type_id="str", + # @value="badger">, + # #<YAML::Syck::Node:0x82ccd58 + # @kind=:scalar, + # @type_id="str", + # @value="elephant">, + # #<YAML::Syck::Node:0x82ccd1c + # @kind=:scalar, + # @type_id="str", + # @value="tiger">]> + # + def YAML.parse_file( filepath ) + File.open( filepath ) do |f| + parse( f ) + end + end + + # + # Calls _block_ with each consecutive document in the YAML + # stream contained in _io_. + # + # File.open( 'many-docs.yaml' ) do |yf| + # YAML.each_document( yf ) do |ydoc| + # ## ydoc contains the single object + # ## from the YAML document + # end + # end + # + def YAML.each_document( io, &block ) + yp = parser.load_documents( io, &block ) + end + + # + # Calls _block_ with each consecutive document in the YAML + # stream contained in _io_. + # + # File.open( 'many-docs.yaml' ) do |yf| + # YAML.load_documents( yf ) do |ydoc| + # ## ydoc contains the single object + # ## from the YAML document + # end + # end + # + def YAML.load_documents( io, &doc_proc ) + YAML.each_document( io, &doc_proc ) + end + + # + # Calls _block_ with a tree of +YAML::BaseNodes+, one tree for + # each consecutive document in the YAML stream contained in _io_. + # + # File.open( 'many-docs.yaml' ) do |yf| + # YAML.each_node( yf ) do |ydoc| + # ## ydoc contains a tree of nodes + # ## from the YAML document + # end + # end + # + def YAML.each_node( io, &doc_proc ) + yp = generic_parser.load_documents( io, &doc_proc ) + end + + # + # Calls _block_ with a tree of +YAML::BaseNodes+, one tree for + # each consecutive document in the YAML stream contained in _io_. + # + # File.open( 'many-docs.yaml' ) do |yf| + # YAML.parse_documents( yf ) do |ydoc| + # ## ydoc contains a tree of nodes + # ## from the YAML document + # end + # end + # + def YAML.parse_documents( io, &doc_proc ) + YAML.each_node( io, &doc_proc ) + end + + # + # Loads all documents from the current _io_ stream, + # returning a +YAML::Stream+ object containing all + # loaded documents. + # + def YAML.load_stream( io ) + d = nil + parser.load_documents( io ) do |doc| + d = YAML::Stream.new if not d + d.add( doc ) + end + return d + end + + # + # Returns a YAML stream containing each of the items in +objs+, + # each having their own document. + # + # YAML.dump_stream( 0, [], {} ) + # #=> --- 0 + # --- [] + # --- {} + # + def YAML.dump_stream( *objs ) + d = YAML::Stream.new + objs.each do |doc| + d.add( doc ) + end + d.emit + end + + # + # Add a global handler for a YAML domain type. + # + def YAML.add_domain_type( domain, type_tag, &transfer_proc ) + resolver.add_type( "tag:#{ domain }:#{ type_tag }", transfer_proc ) + end + + # + # Add a transfer method for a builtin type + # + def YAML.add_builtin_type( type_tag, &transfer_proc ) + resolver.add_type( "tag:yaml.org,2002:#{ type_tag }", transfer_proc ) + end + + # + # Add a transfer method for a builtin type + # + def YAML.add_ruby_type( type_tag, &transfer_proc ) + resolver.add_type( "tag:ruby.yaml.org,2002:#{ type_tag }", transfer_proc ) + end + + # + # Add a private document type + # + def YAML.add_private_type( type_re, &transfer_proc ) + resolver.add_type( "x-private:" + type_re, transfer_proc ) + end + + # + # Detect typing of a string + # + def YAML.detect_implicit( val ) + resolver.detect_implicit( val ) + end + + # + # Convert a type_id to a taguri + # + def YAML.tagurize( val ) + resolver.tagurize( val ) + end + + # + # Apply a transfer method to a Ruby object + # + def YAML.transfer( type_id, obj ) + resolver.transfer( YAML.tagurize( type_id ), obj ) + end + + # + # Apply any implicit a node may qualify for + # + def YAML.try_implicit( obj ) + YAML.transfer( YAML.detect_implicit( obj ), obj ) + end + + # + # Method to extract colon-seperated type and class, returning + # the type and the constant of the class + # + def YAML.read_type_class( type, obj_class ) + scheme, domain, type, tclass = type.split( ':', 4 ) + tclass.split( "::" ).each { |c| obj_class = obj_class.const_get( c ) } if tclass + return [ type, obj_class ] + end + + # + # Allocate blank object + # + def YAML.object_maker( obj_class, val ) + if Hash === val + o = obj_class.allocate + val.each_pair { |k,v| + o.instance_variable_set("@#{k}", v) + } + o + else + raise YAML::Error, "Invalid object explicitly tagged !ruby/Object: " + val.inspect + end + end + + # + # Allocate an Emitter if needed + # + def YAML.quick_emit( oid, opts = {}, &e ) + out = + if opts.is_a? YAML::Emitter + opts + else + emitter.reset( opts ) + end + oid = + case oid when Fixnum, NilClass; oid + else oid = "#{oid.object_id}-#{oid.hash}" + end + out.emit( oid, &e ) + end + +end + +require 'yaml/rubytypes' +require 'yaml/types' + +module Kernel + # + # ryan:: You know how Kernel.p is a really convenient way to dump ruby + # structures? The only downside is that it's not as legible as + # YAML. + # + # _why:: (listening) + # + # ryan:: I know you don't want to urinate all over your users' namespaces. + # But, on the other hand, convenience of dumping for debugging is, + # IMO, a big YAML use case. + # + # _why:: Go nuts! Have a pony parade! + # + # ryan:: Either way, I certainly will have a pony parade. + # + + # Prints any supplied _objects_ out in YAML. Intended as + # a variation on +Kernel::p+. + # + # S = Struct.new(:name, :state) + # s = S['dave', 'TX'] + # y s + # + # _produces:_ + # + # --- !ruby/struct:S + # name: dave + # state: TX + # + def y( object, *objects ) + objects.unshift object + puts( if objects.length == 1 + YAML::dump( *objects ) + else + YAML::dump_stream( *objects ) + end ) + end + private :y +end + + |