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Diffstat (limited to 'ext/json/lib/json/common.rb')
| -rw-r--r-- | ext/json/lib/json/common.rb | 484 |
1 files changed, 484 insertions, 0 deletions
diff --git a/ext/json/lib/json/common.rb b/ext/json/lib/json/common.rb new file mode 100644 index 0000000000..f44184e138 --- /dev/null +++ b/ext/json/lib/json/common.rb @@ -0,0 +1,484 @@ +require 'json/version' +require 'json/generic_object' + +module JSON + class << self + # If _object_ is string-like, parse the string and return the parsed result + # as a Ruby data structure. Otherwise generate a JSON text from the Ruby + # data structure object and return it. + # + # The _opts_ argument is passed through to generate/parse respectively. See + # generate and parse for their documentation. + def [](object, opts = {}) + if object.respond_to? :to_str + JSON.parse(object.to_str, opts) + else + JSON.generate(object, opts) + end + end + + # Returns the JSON parser class that is used by JSON. This is either + # JSON::Ext::Parser or JSON::Pure::Parser. + attr_reader :parser + + # Set the JSON parser class _parser_ to be used by JSON. + def parser=(parser) # :nodoc: + @parser = parser + remove_const :Parser if JSON.const_defined_in?(self, :Parser) + const_set :Parser, parser + end + + # Return the constant located at _path_. The format of _path_ has to be + # either ::A::B::C or A::B::C. In any case, A has to be located at the top + # level (absolute namespace path?). If there doesn't exist a constant at + # the given path, an ArgumentError is raised. + def deep_const_get(path) # :nodoc: + path.to_s.split(/::/).inject(Object) do |p, c| + case + when c.empty? then p + when JSON.const_defined_in?(p, c) then p.const_get(c) + else + begin + p.const_missing(c) + rescue NameError => e + raise ArgumentError, "can't get const #{path}: #{e}" + end + end + end + end + + # Set the module _generator_ to be used by JSON. + def generator=(generator) # :nodoc: + old, $VERBOSE = $VERBOSE, nil + @generator = generator + generator_methods = generator::GeneratorMethods + for const in generator_methods.constants + klass = deep_const_get(const) + modul = generator_methods.const_get(const) + klass.class_eval do + instance_methods(false).each do |m| + m.to_s == 'to_json' and remove_method m + end + include modul + end + end + self.state = generator::State + const_set :State, self.state + const_set :SAFE_STATE_PROTOTYPE, State.new + const_set :FAST_STATE_PROTOTYPE, State.new( + :indent => '', + :space => '', + :object_nl => "", + :array_nl => "", + :max_nesting => false + ) + const_set :PRETTY_STATE_PROTOTYPE, State.new( + :indent => ' ', + :space => ' ', + :object_nl => "\n", + :array_nl => "\n" + ) + ensure + $VERBOSE = old + end + + # Returns the JSON generator module that is used by JSON. This is + # either JSON::Ext::Generator or JSON::Pure::Generator. + attr_reader :generator + + # Returns the JSON generator state class that is used by JSON. This is + # either JSON::Ext::Generator::State or JSON::Pure::Generator::State. + attr_accessor :state + + # This is create identifier, which is used to decide if the _json_create_ + # hook of a class should be called. It defaults to 'json_class'. + attr_accessor :create_id + end + self.create_id = 'json_class' + + NaN = 0.0/0 + + Infinity = 1.0/0 + + MinusInfinity = -Infinity + + # The base exception for JSON errors. + class JSONError < StandardError + def self.wrap(exception) + obj = new("Wrapped(#{exception.class}): #{exception.message.inspect}") + obj.set_backtrace exception.backtrace + obj + end + end + + # This exception is raised if a parser error occurs. + class ParserError < JSONError; end + + # This exception is raised if the nesting of parsed data structures is too + # deep. + class NestingError < ParserError; end + + # :stopdoc: + class CircularDatastructure < NestingError; end + # :startdoc: + + # This exception is raised if a generator or unparser error occurs. + class GeneratorError < JSONError; end + # For backwards compatibility + UnparserError = GeneratorError + + # This exception is raised if the required unicode support is missing on the + # system. Usually this means that the iconv library is not installed. + class MissingUnicodeSupport < JSONError; end + + module_function + + # Parse the JSON document _source_ into a Ruby data structure and return it. + # + # _opts_ can have the following + # keys: + # * *max_nesting*: The maximum depth of nesting allowed in the parsed data + # structures. Disable depth checking with :max_nesting => false. It defaults + # to 100. + # * *allow_nan*: If set to true, allow NaN, Infinity and -Infinity in + # defiance of RFC 4627 to be parsed by the Parser. This option defaults + # to false. + # * *symbolize_names*: If set to true, returns symbols for the names + # (keys) in a JSON object. Otherwise strings are returned. Strings are + # the default. + # * *create_additions*: If set to false, the Parser doesn't create + # additions even if a matching class and create_id was found. This option + # defaults to false. + # * *object_class*: Defaults to Hash + # * *array_class*: Defaults to Array + def parse(source, opts = {}) + Parser.new(source, opts).parse + end + + # Parse the JSON document _source_ into a Ruby data structure and return it. + # The bang version of the parse method defaults to the more dangerous values + # for the _opts_ hash, so be sure only to parse trusted _source_ documents. + # + # _opts_ can have the following keys: + # * *max_nesting*: The maximum depth of nesting allowed in the parsed data + # structures. Enable depth checking with :max_nesting => anInteger. The parse! + # methods defaults to not doing max depth checking: This can be dangerous + # if someone wants to fill up your stack. + # * *allow_nan*: If set to true, allow NaN, Infinity, and -Infinity in + # defiance of RFC 4627 to be parsed by the Parser. This option defaults + # to true. + # * *create_additions*: If set to false, the Parser doesn't create + # additions even if a matching class and create_id was found. This option + # defaults to false. + def parse!(source, opts = {}) + opts = { + :max_nesting => false, + :allow_nan => true + }.update(opts) + Parser.new(source, opts).parse + end + + # Generate a JSON document from the Ruby data structure _obj_ and return + # it. _state_ is * a JSON::State object, + # * or a Hash like object (responding to to_hash), + # * an object convertible into a hash by a to_h method, + # that is used as or to configure a State object. + # + # It defaults to a state object, that creates the shortest possible JSON text + # in one line, checks for circular data structures and doesn't allow NaN, + # Infinity, and -Infinity. + # + # A _state_ hash can have the following keys: + # * *indent*: a string used to indent levels (default: ''), + # * *space*: a string that is put after, a : or , delimiter (default: ''), + # * *space_before*: a string that is put before a : pair delimiter (default: ''), + # * *object_nl*: a string that is put at the end of a JSON object (default: ''), + # * *array_nl*: a string that is put at the end of a JSON array (default: ''), + # * *allow_nan*: true if NaN, Infinity, and -Infinity should be + # generated, otherwise an exception is thrown if these values are + # encountered. This options defaults to false. + # * *max_nesting*: The maximum depth of nesting allowed in the data + # structures from which JSON is to be generated. Disable depth checking + # with :max_nesting => false, it defaults to 100. + # + # See also the fast_generate for the fastest creation method with the least + # amount of sanity checks, and the pretty_generate method for some + # defaults for pretty output. + def generate(obj, opts = nil) + if State === opts + state, opts = opts, nil + else + state = SAFE_STATE_PROTOTYPE.dup + end + if opts + if opts.respond_to? :to_hash + opts = opts.to_hash + elsif opts.respond_to? :to_h + opts = opts.to_h + else + raise TypeError, "can't convert #{opts.class} into Hash" + end + state = state.configure(opts) + end + state.generate(obj) + end + + # :stopdoc: + # I want to deprecate these later, so I'll first be silent about them, and + # later delete them. + alias unparse generate + module_function :unparse + # :startdoc: + + # Generate a JSON document from the Ruby data structure _obj_ and return it. + # This method disables the checks for circles in Ruby objects. + # + # *WARNING*: Be careful not to pass any Ruby data structures with circles as + # _obj_ argument because this will cause JSON to go into an infinite loop. + def fast_generate(obj, opts = nil) + if State === opts + state, opts = opts, nil + else + state = FAST_STATE_PROTOTYPE.dup + end + if opts + if opts.respond_to? :to_hash + opts = opts.to_hash + elsif opts.respond_to? :to_h + opts = opts.to_h + else + raise TypeError, "can't convert #{opts.class} into Hash" + end + state.configure(opts) + end + state.generate(obj) + end + + # :stopdoc: + # I want to deprecate these later, so I'll first be silent about them, and later delete them. + alias fast_unparse fast_generate + module_function :fast_unparse + # :startdoc: + + # Generate a JSON document from the Ruby data structure _obj_ and return it. + # The returned document is a prettier form of the document returned by + # #unparse. + # + # The _opts_ argument can be used to configure the generator. See the + # generate method for a more detailed explanation. + def pretty_generate(obj, opts = nil) + if State === opts + state, opts = opts, nil + else + state = PRETTY_STATE_PROTOTYPE.dup + end + if opts + if opts.respond_to? :to_hash + opts = opts.to_hash + elsif opts.respond_to? :to_h + opts = opts.to_h + else + raise TypeError, "can't convert #{opts.class} into Hash" + end + state.configure(opts) + end + state.generate(obj) + end + + # :stopdoc: + # I want to deprecate these later, so I'll first be silent about them, and later delete them. + alias pretty_unparse pretty_generate + module_function :pretty_unparse + # :startdoc: + + class << self + # The global default options for the JSON.load method: + # :max_nesting: false + # :allow_nan: true + # :quirks_mode: true + attr_accessor :load_default_options + end + self.load_default_options = { + :max_nesting => false, + :allow_nan => true, + :quirks_mode => true, + :create_additions => true, + } + + # Load a ruby data structure from a JSON _source_ and return it. A source can + # either be a string-like object, an IO-like object, or an object responding + # to the read method. If _proc_ was given, it will be called with any nested + # Ruby object as an argument recursively in depth first order. To modify the + # default options pass in the optional _options_ argument as well. + # + # BEWARE: This method is meant to serialise data from trusted user input, + # like from your own database server or clients under your control, it could + # be dangerous to allow untrusted users to pass JSON sources into it. The + # default options for the parser can be changed via the load_default_options + # method. + # + # This method is part of the implementation of the load/dump interface of + # Marshal and YAML. + def load(source, proc = nil, options = {}) + opts = load_default_options.merge options + if source.respond_to? :to_str + source = source.to_str + elsif source.respond_to? :to_io + source = source.to_io.read + elsif source.respond_to?(:read) + source = source.read + end + if opts[:quirks_mode] && (source.nil? || source.empty?) + source = 'null' + end + result = parse(source, opts) + recurse_proc(result, &proc) if proc + result + end + + # Recursively calls passed _Proc_ if the parsed data structure is an _Array_ or _Hash_ + def recurse_proc(result, &proc) + case result + when Array + result.each { |x| recurse_proc x, &proc } + proc.call result + when Hash + result.each { |x, y| recurse_proc x, &proc; recurse_proc y, &proc } + proc.call result + else + proc.call result + end + end + + alias restore load + module_function :restore + + class << self + # The global default options for the JSON.dump method: + # :max_nesting: false + # :allow_nan: true + # :quirks_mode: true + attr_accessor :dump_default_options + end + self.dump_default_options = { + :max_nesting => false, + :allow_nan => true, + :quirks_mode => true, + } + + # Dumps _obj_ as a JSON string, i.e. calls generate on the object and returns + # the result. + # + # If anIO (an IO-like object or an object that responds to the write method) + # was given, the resulting JSON is written to it. + # + # If the number of nested arrays or objects exceeds _limit_, an ArgumentError + # exception is raised. This argument is similar (but not exactly the + # same!) to the _limit_ argument in Marshal.dump. + # + # The default options for the generator can be changed via the + # dump_default_options method. + # + # This method is part of the implementation of the load/dump interface of + # Marshal and YAML. + def dump(obj, anIO = nil, limit = nil) + if anIO and limit.nil? + anIO = anIO.to_io if anIO.respond_to?(:to_io) + unless anIO.respond_to?(:write) + limit = anIO + anIO = nil + end + end + opts = JSON.dump_default_options + opts = opts.merge(:max_nesting => limit) if limit + result = generate(obj, opts) + if anIO + anIO.write result + anIO + else + result + end + rescue JSON::NestingError + raise ArgumentError, "exceed depth limit" + end + + # Swap consecutive bytes of _string_ in place. + def self.swap!(string) # :nodoc: + 0.upto(string.size / 2) do |i| + break unless string[2 * i + 1] + string[2 * i], string[2 * i + 1] = string[2 * i + 1], string[2 * i] + end + string + end + + # Shortcut for iconv. + if ::String.method_defined?(:encode) + # Encodes string using Ruby's _String.encode_ + def self.iconv(to, from, string) + string.encode(to, from) + end + else + require 'iconv' + # Encodes string using _iconv_ library + def self.iconv(to, from, string) + Iconv.conv(to, from, string) + end + end + + if ::Object.method(:const_defined?).arity == 1 + def self.const_defined_in?(modul, constant) + modul.const_defined?(constant) + end + else + def self.const_defined_in?(modul, constant) + modul.const_defined?(constant, false) + end + end +end + +module ::Kernel + private + + # Outputs _objs_ to STDOUT as JSON strings in the shortest form, that is in + # one line. + def j(*objs) + objs.each do |obj| + puts JSON::generate(obj, :allow_nan => true, :max_nesting => false) + end + nil + end + + # Outputs _objs_ to STDOUT as JSON strings in a pretty format, with + # indentation and over many lines. + def jj(*objs) + objs.each do |obj| + puts JSON::pretty_generate(obj, :allow_nan => true, :max_nesting => false) + end + nil + end + + # If _object_ is string-like, parse the string and return the parsed result as + # a Ruby data structure. Otherwise, generate a JSON text from the Ruby data + # structure object and return it. + # + # The _opts_ argument is passed through to generate/parse respectively. See + # generate and parse for their documentation. + def JSON(object, *args) + if object.respond_to? :to_str + JSON.parse(object.to_str, args.first) + else + JSON.generate(object, args.first) + end + end +end + +# Extends any Class to include _json_creatable?_ method. +class ::Class + # Returns true if this class can be used to create an instance + # from a serialised JSON string. The class has to implement a class + # method _json_create_ that expects a hash as first parameter. The hash + # should include the required data. + def json_creatable? + respond_to?(:json_create) + end +end |