The Warning
module contains a single method named warn
, and the module extends itself, making Warning.warn
available. Warning.warn
is called for all warnings issued by Ruby. By default, warnings are printed to $stderr.
Changing the behavior of Warning.warn
is useful to customize how warnings are handled by Ruby, for instance by filtering some warnings, and/or outputting warnings somewhere other than $stderr
.
If you want to change the behavior of Warning.warn
you should use Warning.extend(MyNewModuleWithWarnMethod)
and you can use super
to get the default behavior of printing the warning to $stderr
.
Example:
module MyWarningFilter def warn(message, category: nil, **kwargs) if /some warning I want to ignore/.match?(message) # ignore else super end end end Warning.extend MyWarningFilter
You should never redefine Warning#warn
(the instance method), as that will then no longer provide a way to use the default behavior.
The warning gem provides convenient ways to customize Warning.warn
.
Coverage
provides coverage measurement feature for Ruby. This feature is experimental, so these APIs may be changed in future.
Caveat: Currently, only process-global coverage measurement is supported. You cannot measure per-thread coverage.
require “coverage”
require or load Ruby source file
Coverage.result
will return a hash that contains filename as key and coverage array as value. A coverage array gives, for each line, the number of line execution by the interpreter. A nil
value means coverage is disabled for this line (lines like else
and end
).
[foo.rb] s = 0 10.times do |x| s += x end if s == 45 p :ok else p :ng end [EOF] require "coverage" Coverage.start require "foo.rb" p Coverage.result #=> {"foo.rb"=>[1, 1, 10, nil, nil, 1, 1, nil, 0, nil]}
Coverage
If a coverage mode is not explicitly specified when starting coverage, lines coverage is what will run. It reports the number of line executions for each line.
require "coverage" Coverage.start(lines: true) require "foo.rb" p Coverage.result #=> {"foo.rb"=>{:lines=>[1, 1, 10, nil, nil, 1, 1, nil, 0, nil]}}
The value of the lines coverage result is an array containing how many times each line was executed. Order in this array is important. For example, the first item in this array, at index 0, reports how many times line 1 of this file was executed while coverage was run (which, in this example, is one time).
A nil
value means coverage is disabled for this line (lines like else
and end
).
Coverage
Oneshot lines coverage tracks and reports on the executed lines while coverage is running. It will not report how many times a line was executed, only that it was executed.
require "coverage" Coverage.start(oneshot_lines: true) require "foo.rb" p Coverage.result #=> {"foo.rb"=>{:oneshot_lines=>[1, 2, 3, 6, 7]}}
The value of the oneshot lines coverage result is an array containing the line numbers that were executed.
Coverage
Branches coverage reports how many times each branch within each conditional was executed.
require "coverage" Coverage.start(branches: true) require "foo.rb" p Coverage.result #=> {"foo.rb"=>{:branches=>{[:if, 0, 6, 0, 10, 3]=>{[:then, 1, 7, 2, 7, 7]=>1, [:else, 2, 9, 2, 9, 7]=>0}}}}
Each entry within the branches hash is a conditional, the value of which is another hash where each entry is a branch in that conditional. The values are the number of times the method was executed, and the keys are identifying information about the branch.
The information that makes up each key identifying branches or conditionals is the following, from left to right:
A label for the type of branch or conditional.
A unique identifier.
The starting line number it appears on in the file.
The starting column number it appears on in the file.
The ending line number it appears on in the file.
The ending column number it appears on in the file.
Coverage
Methods coverage reports how many times each method was executed.
[foo_method.rb] class Greeter def greet "welcome!" end end def hello "Hi" end hello() Greeter.new.greet() [EOF] require "coverage" Coverage.start(methods: true) require "foo_method.rb" p Coverage.result #=> {"foo_method.rb"=>{:methods=>{[Object, :hello, 7, 0, 9, 3]=>1, [Greeter, :greet, 2, 2, 4, 5]=>1}}}
Each entry within the methods hash represents a method. The values in this hash are the number of times the method was executed, and the keys are identifying information about the method.
The information that makes up each key identifying a method is the following, from left to right:
The class.
The method name.
The starting line number the method appears on in the file.
The starting column number the method appears on in the file.
The ending line number the method appears on in the file.
The ending column number the method appears on in the file.
Coverage
Modes You can also run all modes of coverage simultaneously with this shortcut. Note that running all coverage modes does not run both lines and oneshot lines. Those modes cannot be run simultaneously. Lines coverage is run in this case, because you can still use it to determine whether or not a line was executed.
require "coverage" Coverage.start(:all) require "foo.rb" p Coverage.result #=> {"foo.rb"=>{:lines=>[1, 1, 10, nil, nil, 1, 1, nil, 0, nil], :branches=>{[:if, 0, 6, 0, 10, 3]=>{[:then, 1, 7, 2, 7, 7]=>1, [:else, 2, 9, 2, 9, 7]=>0}}, :methods=>{}}}
The Benchmark
module provides methods to measure and report the time used to execute Ruby code.
Measure the time to construct the string given by the expression "a"*1_000_000_000
:
require 'benchmark' puts Benchmark.measure { "a"*1_000_000_000 }
On my machine (OSX 10.8.3 on i5 1.7 GHz) this generates:
0.350000 0.400000 0.750000 ( 0.835234)
This report shows the user CPU time, system CPU time, the sum of the user and system CPU times, and the elapsed real time. The unit of time is seconds.
Do some experiments sequentially using the bm
method:
require 'benchmark' n = 5000000 Benchmark.bm do |x| x.report { for i in 1..n; a = "1"; end } x.report { n.times do ; a = "1"; end } x.report { 1.upto(n) do ; a = "1"; end } end
The result:
user system total real 1.010000 0.000000 1.010000 ( 1.014479) 1.000000 0.000000 1.000000 ( 0.998261) 0.980000 0.000000 0.980000 ( 0.981335)
Continuing the previous example, put a label in each report:
require 'benchmark' n = 5000000 Benchmark.bm(7) do |x| x.report("for:") { for i in 1..n; a = "1"; end } x.report("times:") { n.times do ; a = "1"; end } x.report("upto:") { 1.upto(n) do ; a = "1"; end } end
The result:
user system total real for: 1.010000 0.000000 1.010000 ( 1.015688) times: 1.000000 0.000000 1.000000 ( 1.003611) upto: 1.030000 0.000000 1.030000 ( 1.028098)
The times for some benchmarks depend on the order in which items are run. These differences are due to the cost of memory allocation and garbage collection. To avoid these discrepancies, the bmbm
method is provided. For example, to compare ways to sort an array of floats:
require 'benchmark' array = (1..1000000).map { rand } Benchmark.bmbm do |x| x.report("sort!") { array.dup.sort! } x.report("sort") { array.dup.sort } end
The result:
Rehearsal ----------------------------------------- sort! 1.490000 0.010000 1.500000 ( 1.490520) sort 1.460000 0.000000 1.460000 ( 1.463025) -------------------------------- total: 2.960000sec user system total real sort! 1.460000 0.000000 1.460000 ( 1.460465) sort 1.450000 0.010000 1.460000 ( 1.448327)
Report statistics of sequential experiments with unique labels, using the benchmark
method:
require 'benchmark' include Benchmark # we need the CAPTION and FORMAT constants n = 5000000 Benchmark.benchmark(CAPTION, 7, FORMAT, ">total:", ">avg:") do |x| tf = x.report("for:") { for i in 1..n; a = "1"; end } tt = x.report("times:") { n.times do ; a = "1"; end } tu = x.report("upto:") { 1.upto(n) do ; a = "1"; end } [tf+tt+tu, (tf+tt+tu)/3] end
The result:
user system total real for: 0.950000 0.000000 0.950000 ( 0.952039) times: 0.980000 0.000000 0.980000 ( 0.984938) upto: 0.950000 0.000000 0.950000 ( 0.946787) >total: 2.880000 0.000000 2.880000 ( 2.883764) >avg: 0.960000 0.000000 0.960000 ( 0.961255)
The Forwardable
module provides delegation of specified methods to a designated object, using the methods def_delegator
and def_delegators
.
For example, say you have a class RecordCollection which contains an array @records
. You could provide the lookup method record_number(), which simply calls [] on the @records
array, like this:
require 'forwardable' class RecordCollection attr_accessor :records extend Forwardable def_delegator :@records, :[], :record_number end
We can use the lookup method like so:
r = RecordCollection.new r.records = [4,5,6] r.record_number(0) # => 4
Further, if you wish to provide the methods size, <<, and map, all of which delegate to @records, this is how you can do it:
class RecordCollection # re-open RecordCollection class def_delegators :@records, :size, :<<, :map end r = RecordCollection.new r.records = [1,2,3] r.record_number(0) # => 1 r.size # => 3 r << 4 # => [1, 2, 3, 4] r.map { |x| x * 2 } # => [2, 4, 6, 8]
You can even extend regular objects with Forwardable
.
my_hash = Hash.new my_hash.extend Forwardable # prepare object for delegation my_hash.def_delegator "STDOUT", "puts" # add delegation for STDOUT.puts() my_hash.puts "Howdy!"
You could use Forwardable
as an alternative to inheritance, when you don’t want to inherit all methods from the superclass. For instance, here is how you might add a range of Array
instance methods to a new class Queue
:
class Queue extend Forwardable def initialize @q = [ ] # prepare delegate object end # setup preferred interface, enq() and deq()... def_delegator :@q, :push, :enq def_delegator :@q, :shift, :deq # support some general Array methods that fit Queues well def_delegators :@q, :clear, :first, :push, :shift, :size end q = Thread::Queue.new q.enq 1, 2, 3, 4, 5 q.push 6 q.shift # => 1 while q.size > 0 puts q.deq end q.enq "Ruby", "Perl", "Python" puts q.first q.clear puts q.first
This should output:
2 3 4 5 6 Ruby nil
Be advised, RDoc
will not detect delegated methods.
forwardable.rb
provides single-method delegation via the def_delegator
and def_delegators
methods. For full-class delegation via DelegateClass, see delegate.rb
.
SingleForwardable
can be used to setup delegation at the object level as well.
printer = String.new printer.extend SingleForwardable # prepare object for delegation printer.def_delegator "STDOUT", "puts" # add delegation for STDOUT.puts() printer.puts "Howdy!"
Also, SingleForwardable
can be used to set up delegation for a Class
or Module
.
class Implementation def self.service puts "serviced!" end end module Facade extend SingleForwardable def_delegator :Implementation, :service end Facade.service #=> serviced!
If you want to use both Forwardable
and SingleForwardable
, you can use methods def_instance_delegator and def_single_delegator
, etc.
This library is an interface to secure random number generators which are suitable for generating session keys in HTTP cookies, etc.
You can use this library in your application by requiring it:
require 'securerandom'
It supports the following secure random number generators:
openssl
/dev/urandom
SecureRandom
is extended by the Random::Formatter
module which defines the following methods:
alphanumeric
base64
choose
gen_random
hex
rand
random_bytes
random_number
urlsafe_base64
uuid
These methods are usable as class methods of SecureRandom
such as SecureRandom.hex
.
If a secure random number generator is not available, NotImplementedError
is raised.
The marshaling library converts collections of Ruby objects into a byte stream, allowing them to be stored outside the currently active script. This data may subsequently be read and the original objects reconstituted.
Marshaled data has major and minor version numbers stored along with the object information. In normal use, marshaling can only load data written with the same major version number and an equal or lower minor version number. If Ruby’s “verbose” flag is set (normally using -d, -v, -w, or –verbose) the major and minor numbers must match exactly. Marshal
versioning is independent of Ruby’s version numbers. You can extract the version by reading the first two bytes of marshaled data.
str = Marshal.dump("thing") RUBY_VERSION #=> "1.9.0" str[0].ord #=> 4 str[1].ord #=> 8
Some objects cannot be dumped: if the objects to be dumped include bindings, procedure or method objects, instances of class IO
, or singleton objects, a TypeError
will be raised.
If your class has special serialization needs (for example, if you want to serialize in some specific format), or if it contains objects that would otherwise not be serializable, you can implement your own serialization strategy.
There are two methods of doing this, your object can define either marshal_dump and marshal_load or _dump and _load. marshal_dump will take precedence over _dump if both are defined. marshal_dump may result in smaller Marshal
strings.
By design, Marshal.load
can deserialize almost any class loaded into the Ruby process. In many cases this can lead to remote code execution if the Marshal
data is loaded from an untrusted source.
As a result, Marshal.load
is not suitable as a general purpose serialization format and you should never unmarshal user supplied input or other untrusted data.
If you need to deserialize untrusted data, use JSON
or another serialization format that is only able to load simple, ‘primitive’ types such as String
, Array
, Hash
, etc. Never allow user input to specify arbitrary types to deserialize into.
When dumping an object the method marshal_dump will be called. marshal_dump must return a result containing the information necessary for marshal_load to reconstitute the object. The result can be any object.
When loading an object dumped using marshal_dump the object is first allocated then marshal_load is called with the result from marshal_dump. marshal_load must recreate the object from the information in the result.
Example:
class MyObj def initialize name, version, data @name = name @version = version @data = data end def marshal_dump [@name, @version] end def marshal_load array @name, @version = array end end
Use _dump and _load when you need to allocate the object you’re restoring yourself.
When dumping an object the instance method _dump is called with an Integer
which indicates the maximum depth of objects to dump (a value of -1 implies that you should disable depth checking). _dump must return a String
containing the information necessary to reconstitute the object.
The class method _load should take a String
and use it to return an object of the same class.
Example:
class MyObj def initialize name, version, data @name = name @version = version @data = data end def _dump level [@name, @version].join ':' end def self._load args new(*args.split(':')) end end
Since Marshal.dump
outputs a string you can have _dump return a Marshal
string which is Marshal.loaded in _load for complex objects.
Creates a DRb::DRbObject
given the reference information to the remote host uri
and object ref
.
Creates a DRb::DRbObject
given the reference information to the remote host uri
and object ref
.
Ignored newlines can occasionally have a LABEL state attached to them, so we compare the state differently here.
Construct a new BlockCaller
object.
ctype
is the C type to be returned
args
are passed the callback
abi
is the abi of the closure
If there is an error in preparing the ffi_cif
or ffi_prep_closure
, then a RuntimeError
will be raised.
include Fiddle cb = Closure::BlockCaller.new(TYPE_INT, [TYPE_INT]) do |one| one end func = Function.new(cb, [TYPE_INT], TYPE_INT)
Creates a new JSON::Ext::Parser
instance for the string source.
It will be configured by the opts hash. opts can have the following keys:
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|nil|0, 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, which is also the default. It’s not possible to use this option in conjunction with the create_additions option.
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
Creates a new instance of OpenSSL::PKey::DH
.
If called without arguments, an empty instance without any parameter or key components is created. Use set_pqg
to manually set the parameters afterwards (and optionally set_key
to set private and public key components).
If a String
is given, tries to parse it as a DER- or PEM- encoded parameters. See also OpenSSL::PKey.read
which can parse keys of any kinds.
The DH.new
(size [, generator]) form is an alias of DH.generate
.
string
A String
that contains the DER or PEM encoded key.
size
See DH.generate
.
generator
See DH.generate
.
Examples:
# Creating an instance from scratch # Note that this is deprecated and will not work on OpenSSL 3.0 or later. dh = OpenSSL::PKey::DH.new dh.set_pqg(bn_p, nil, bn_g) # Generating a parameters and a key pair dh = OpenSSL::PKey::DH.new(2048) # An alias of OpenSSL::PKey::DH.generate(2048) # Reading DH parameters dh_params = OpenSSL::PKey::DH.new(File.read('parameters.pem')) # loads parameters only dh = OpenSSL::PKey.generate_key(dh_params) # generates a key pair
Creates a new DSA
instance by reading an existing key from string.
If called without arguments, creates a new instance with no key components set. They can be set individually by set_pqg
and set_key
.
If called with a String
, tries to parse as DER or PEM encoding of a DSA key. See also OpenSSL::PKey.read
which can parse keys of any kinds.
If called with a number, generates random parameters and a key pair. This form works as an alias of DSA.generate
.
string
A String
that contains a DER or PEM encoded key.
pass
A String
that contains an optional password.
size
See DSA.generate
.
Examples:
p OpenSSL::PKey::DSA.new(1024) #=> #<OpenSSL::PKey::DSA:0x000055a8d6025bf0 oid=DSA> p OpenSSL::PKey::DSA.new(File.read('dsa.pem')) #=> #<OpenSSL::PKey::DSA:0x000055555d6b8110 oid=DSA> p OpenSSL::PKey::DSA.new(File.read('dsa.pem'), 'mypassword') #=> #<OpenSSL::PKey::DSA:0x0000556f973c40b8 oid=DSA>
Creates a new EC
object from given arguments.
Generates or loads an RSA keypair.
If called without arguments, creates a new instance with no key components set. They can be set individually by set_key
, set_factors
, and set_crt_params
.
If called with a String
, tries to parse as DER or PEM encoding of an RSA key. Note that if password is not specified, but the key is encrypted with a password, OpenSSL will prompt for it. See also OpenSSL::PKey.read
which can parse keys of any kind.
If called with a number, generates a new key pair. This form works as an alias of RSA.generate
.
Examples:
OpenSSL::PKey::RSA.new 2048 OpenSSL::PKey::RSA.new File.read 'rsa.pem' OpenSSL::PKey::RSA.new File.read('rsa.pem'), 'my password'