ruby.org

数学计算

  1. Ruby参考

在计算三角函数sina，cos，或者各种指数，平方根时，必须在程序前面加上include Math这一句话。sin值可以用sina方法求的，平方根可以用sprt 方法求的。

下面，让我们尝试计算3的平方：

3**2

在Ruby语言中，**表示幂运算。那么如何计算平方根呢？ 

include Math
print("sin(3.14)=",sin(3.14),"\n")
print("cos(3.14)=",cos(3.14),"\n")
print("sqrt(10000)=",sqrt(10000),"\n")

----

ruby differ

http://github.com/pvande/differ 

will@will-laptop:~/Desktop/diff$ irb -rubygems
irb(main):001:0> irb -rubygems
NameError: undefined local variable or method `rubygems' for main:Object
	from (irb):1
irb(main):002:0> require 'differ'
=> true
irb(main):003:0> @original = "Epic lolcat fail!"
=> "Epic lolcat fail!"
irb(main):004:0>   @current  = "Epic wolfman fail!"
=> "Epic wolfman fail!"
irb(main):005:0> @diff = Differ.diff_by_line(@current, @original)
=> #<Differ::Diff:0xb75103a8 @raw=[{"Epic lolcat fail!" >> "Epic wolfman fail!"}]>
irb(main):006:0> require 'differ/string'
=> true
irb(main):007:0> @diff = (@current - @original)
=> #<Differ::Diff:0xb750a110 @raw=[{"Epic lolcat fail!" >> "Epic wolfman fail!"}]>
irb(main):008:0>   @diff.format_as(:color)
=> "\e[31mEpic lolcat fail!\e[0m\e[32mEpic wolfman fail!\e[0m"
irb(main):009:0>   @diff.format_as(:html)
=> "<del class=\"differ\">Epic lolcat fail!</del><ins class=\"differ\">Epic wolfman fail!</ins>"
irb(main):010:0> $; = ' '
=> " "
irb(main):011:0> @diff = (@current - @original)
=> #<Differ::Diff:0xb74fdc44 @raw=["Epic ", {"lolcat" >> "wolfman"}, " fail!"]>
irb(main):012:0>   @diff.format_as(:html)
=> "Epic <del class=\"differ\">lolcat</del><ins class=\"differ\">wolfman</ins> fail!"
irb(main):013:0> $; = ';'
=> ";"
irb(main):014:0> @diff = (@current - @original)
=> #<Differ::Diff:0xb74f3014 @raw=[{"Epic lolcat fail!" >> "Epic wolfman fail!"}]>
irb(main):015:0>

Execute cmd and get the output

IO.popen("help") {|d| d.readlines.each {|x|puts x} }

Ruy gem

http://rubygems.org/read/chapter/5 http://www.hhtong.com/blog1/articles/2007/06/10/ruby-gpgen-20070603 

gem install gem_plugin 
gpgen easywebtest

RubyGems是一个库和程序的标准化打包以及安装框架，它使定位、安装、升级和卸载Ruby包变的很容易。rails以及它的大部分插件都是以gem形式发布的。本文描述一个自己创建ruby Gems的过程。 假设你今天用ruby实现了一个stack结构，你想发布到网上让别人可以共享，OK，工作开始了。首先你的程序当然要先写好了： Ruby代码

  1. #stacklike.rb
  2. module Stacklike
  3. attr_reader:stack
  4. def initialize
  5. @stack=Array.new
  6. end
  7. def add_to_stack(obj)
  8. @stack.push(obj)
  9. end
  10. def take_from_stack
  11. @stack.pop
  12. end
  13. def size
  14. @stack.length
  15. end
  16. alias length size
  18. def clear
  19. @stack.clear
  20. end
  21. end

#stacklike.rb module Stacklike attr_reader:stack def initialize @stack=Array.new end def add_to_stack(obj) @stack.push(obj) end def take_from_stack @stack.pop end def size @stack.length end alias length size

def clear @stack.clear end end

然后就是我们的Stack类，引入这个Module，请注意，我们这里只是特意这样做，增加点复杂度： Ruby代码

  1. #stack.rb
  2. require 'stacklike'
  3. class Stack
  4. include Stacklike
  5. end

#stack.rb require 'stacklike' class Stack include Stacklike end

作为一个要被"大众"使用的小程序，一定要有完备的测试代码，OK,ruby内置了单元测试库，我们来写个单元测试来测试Stack： Ruby代码

  1. require 'stack'
  2. require 'test/unit'
  3. class TestStack <Test::Unit::TestCase
  4. def testStack
  5. stack=Stack.new
  6. assert_equal(0,stack.size)
  7. assert_equal(stack.length,stack.size)
  8. stack.add_to_stack(1)
  9. assert_equal(1,stack.length)
  10. assert_equal(1,stack.take_from_stack)
  12. stack.clear
  13. assert_equal(0,stack.length)
  14. assert_nil(stack.take_from_stack)
  16. 10.times{|i| stack.add_to_stack(i)}
  17. assert_equal(10,stack.size)
  18. assert_equal(stack.length,stack.size)
  19. 9.downto(4){|i| assert_equal(i,stack.take_from_stack)}
  21. assert_equal(4,stack.length)
  22. assert_equal(3,stack.take_from_stack)
  23. assert_equal(3,stack.length)
  25. stack.clear
  26. assert_equal(0,stack.length)
  27. assert_nil(stack.take_from_stack)
  28. end
  29. end

require 'stack' require 'test/unit' class TestStack <Test::Unit::TestCase def testStack stack=Stack.new assert_equal(0,stack.size) assert_equal(stack.length,stack.size) stack.add_to_stack(1) assert_equal(1,stack.length) assert_equal(1,stack.take_from_stack)

stack.clear assert_equal(0,stack.length) assert_nil(stack.take_from_stack)

10.times{|i| stack.add_to_stack(i)} assert_equal(10,stack.size) assert_equal(stack.length,stack.size) 9.downto(4){|i| assert_equal(i,stack.take_from_stack)}

assert_equal(4,stack.length) assert_equal(3,stack.take_from_stack) assert_equal(3,stack.length)

stack.clear assert_equal(0,stack.length) assert_nil(stack.take_from_stack) end end

如果你使用radrails或者RDT运行这段代码，你将看到让人舒服的greenbar，一切正常。程序写好了，接下来就是关键步骤了，怎么发布成ruby Gems呢？

第一步，写Gems规范文件 gemspec是ruby或者YAML形式的元数据集，用来提供这个gem的关键信息，我们创建一个文件夹就叫stack，然后在下面建立2个目录两个文件： lib目录：用于存放库的源代码，比如这个例子中的stack.rb,stacklike.rb test目录：用于存放单元测试代码。 README文件：描述你的库的基本信息和版权许可证等 stack.gemspec：gems规范文件，用以生成gem 当然，也可以有docs目录用以存放rdoc文档和ext目录用以存放ruby扩展，我们这个简单例子就免了。 看看我们的规范文件： Ruby代码

  1. #stack.spec
  2. require 'rubygems'
  3. SPEC=Gem::Specification.new do |s|
  4. s.name="Stack"
  5. s.version='0.01'
  6. s.author='dennis zane'
  7. s.email="killme2008@gmail.com"
  8. s.homepage="http://www.rubyeye.net"
  9. s.platform=Gem::Platform::RUBY
  10. s.summary="ruby实现的Stack"
  11. condidates =Dir.glob("{bin,lib,docs,test}/**/*")
  12. s.files=condidates.delete_if do |item|
  13. item.include?("CVS")|| item.include?("rdoc")
  14. end
  15. s.require_path="lib"
  16. s.autorequire='stack,stacklike'
  17. s.test_file="test/ts_stack.rb"
  18. s.has_rdoc=false
  19. s.extra_rdoc_files=["README"]
  20. end 
#stack.spec
require 'rubygems'
SPEC=Gem::Specification.new do |s|
  s.name="Stack"
  s.version='0.01'
  s.author='dennis zane'
  s.email="killme2008@gmail.com"
  s.homepage="http://www.rubyeye.net"
  s.platform=Gem::Platform::RUBY
  s.summary="ruby实现的Stack"
  condidates =Dir.glob("{bin,lib,docs,test}/**/*")
  s.files=condidates.delete_if do |item|
    item.include?("CVS")|| item.include?("rdoc")
  end
  s.require_path="lib"
  s.autorequire='stack,stacklike'
  s.test_file="test/ts_stack.rb"
  s.has_rdoc=false
  s.extra_rdoc_files=["README"]
end

很明显，规范文件也是ruby程序（也可以用YAML描述），设置了这个gem的主要关键信息：名称、作者信息、平台,需要注意的就是files 数组过滤掉了cvs和rdoc文件，require_path和auto_require让你指定了require_gem装入gem时会被添加到$ LOAS_PATH（ruby查找库的路径）中的目录（也就是我们源代码存放的lib），auto_require指定了装载的文件名，我们没有 rdoc，所有设置has_rdoc为false，附带文档就是README。

第二步 修改单元测试文件引用路径 过去我们假设ts_stack.rb与stack.rb、stacklike.rb在同一个目录下，可是我们现在将它们分别放在lib和test目录，TestStack 怎么引用测试的类呢？答案是在ts_stack.rb开头加上一行： Ruby代码

  1. $:.unshift File.join(File.dirname(FILE),"..","lib")

$:.unshift File.join(File.dirname(FILE),"..","lib")

最后一步 构建gem 在stack目录执行下列命令： Ruby代码

  1. ruby stack.gemspec

ruby stack.gemspec

或者: Ruby代码

  1. gem build stack.gemspec

gem build stack.gemspec

将生成一个文件，你可以将这个文件共享给朋友们咯。你的朋友只要下载这个文件，执行： Ruby代码

  1. gem install Stack.0.01.gem

gem install Stack.0.01.gem

将在他们的ruby环境中安装你写的stack，比较遗憾的是，你这个stack确实太简陋了，哈哈。

web server

http://snippets.dzone.com/tag/webrick

  • Ruby send mail with attathment 
gem install actionmailer
gem install mime-types

Ruby dummy mail server

  gem sources -a http://gems.github.com
  gem install koseki-mocksmtpd
cd ~/.gem/ruby/1.8/bin
  ./mocksmtpd  init ~/testmail
  sudo ./mocksmtpd -f ~/testmail/mocksmtpd.conf

send mail to test@changweilaptop.dyn.webahead.ibm.com

You will get the mail in file:///home/will/testmail/inbox/index.html

But the mail body is not readable.

Ruby to exe

http://rubyforge.org/projects/ocra

http://github.com/larsch/ocra

（水果党和 linuser 先站一边去 ……） One-Click Ruby Application，就是把解释器、gem 什么的打包在一起做成独立 exe。 比 rubyscript2exe 和 exerb 先进，支持 1.9。

安装： Console代码 gem install ocra

或者下载 stand alone not complex 的 .exe

假设要把 testo.rb 做成 exe，只需： Console代码 ocra.rb.bat testo.rb

输出看起来像这样（它把用到的东西都打包到 exe 里面了）： = Loading script to check dependencies testo vooo = Building testo.exe m #+BEGIN_SRC a #+BEGIN_SRC m bin a bin\ruby.exe a bin\msvcr100-ruby191.dll a bin\MSVCR100.dll m lib m lib\ruby m lib\ruby\1.9.1 m lib\ruby\1.9.1\i386-mswin32_100 m lib\ruby\1.9.1\i386-mswin32_100\enc a lib\ruby\1.9.1\i386-mswin32_100\enc\encdb.so a lib\ruby\1.9.1\i386-mswin32_100\enc\euc_kr.so a lib\ruby\1.9.1\i386-mswin32_100\enc\gb2312.so m lib\ruby\1.9.1\i386-mswin32_100\enc\trans a lib\ruby\1.9.1\i386-mswin32_100\enc\trans\transdb.so a lib\ruby\1.9.1\i386-mswin32_100\enc\gbk.so a lib\ruby\1.9.1\rubygems.rb e RUBYOPT rubygems e RUBYLIB l bin\ruby.exe ruby.exe

#+BEGIN_SRC = Compressing = Finished (Final size was 781622) - 只有 781k 的 standalone

一些琐碎的东西：

ocra 之前，路径变量中应该包含 ruby_home\bin，ocra 是根据 path 中找到的第一个 ruby 解释器来决定库文件位置的。设定路径变量例： Console代码 set path=d:\Ruby\ruby1.9.1\bin;%path%

需要 win32-api gem，如果你的 ruby 不是官方 1.8.x 二进制，安装 win32-api gem 前记得先把编译器环境设好。

一般 ocra 一个文件就行了（例如你要打包一个 rails app 的话，就去 ocra.rb.bat script\server） 有些依赖关系不能通过 require 或者 load 体现，得手动添加。例子：（添加图片和一个目录） Cosole代码 ocra.rb.bat mainscript.rb someimage.jpeg docs/

对于 GUI 程序，在 main loop 之前加个判断，避免在打包过程中启动程序弹出窗口： Ruby代码 unless defined? Ocra app.main_loop end

注意工作目录，最简易的手段是加上 Ruby代码 Dir.chdir File.dirname FILE

某些情况可能需要 mingw 编译 stub，所以到 http://rubyinstaller.org/downloads/ 下载一个 devkit 可以有备无患。

可用选项： Options代码 --dll dllname 将额外的 dll 包含进 bin 目录 --no-lzma 取消可执行文件的 LZMA 压缩（体积大一点，运行是否快一点就看你硬盘不是/是 SSD 了） --quiet 格林..达姆自己 --help 显示帮助 --windows 产生窗口程序（rubyw.exe） --console 产生控制台程序（ruby.exe） --no-autoload 不预先加载/包含脚本文件的 autoloads（感觉对速度没什么影响） --icon <ico> 自定图标 --version 显示版本号

Ruby trick

http://www.javaeye.com/topic/414412

<#+BEGIN_SRC > match, text, number = * "Something 981".match(([A-z]*) ([0-9]*)) #+END_SRC

hash作参数：

Ruby代码 <#+BEGIN_SRC > def m option={} arg2 = option[:arg2] arg1 = option[:arg1] print arg2,arg1 end

m :arg2 =>"Hi", :arg1 = > "hooopo" #Hihooopo

#+END_SRC

JRuby

jruby -S gem install antwrap

Jruby on rails

DB2

this version run gem install ibm_db on Windows. On Linux run the following: <#+BEGIN_SRC > $ . /home/db2inst1/db2profile $ export IBM_DB_DIR=/opt/ibm/db2/V9.5 $ export IBM_DB_LIB=/opt/ibm/db2/V9.5/lib32 $ sudo gem install ibm_db #+END_SRC

mail

<#+BEGIN_SRC > require 'rubygems' require 'action_mailer' require 'mime/types'

ActionMailer::Base.smtp_settings = { :address => '10.209.3.26', :domain => '3dlabs.com'}

class Mailer < ActionMailer::Base def message (title, body) from 'Dave Baldwin <dave.baldwin@...>' recipients 'dave.baldwin@...' subject title body body

FileList['PDF/*.pdf'].each do |path| file = File.basename(path) mime_type = MIME::Types.of(file).first content_type = mime_type ? mime_type.content_type : 'application/ binary' attachment (content_type) do |a| a.body = File.read(path) a.filename = file a.transfer_encoding = 'quoted-printable' if content_type =~ ^text \/ end end end end

Mailer.deliver_message('some title', 'the body message')

#+END_SRC

passing parameter to ruby main

if ARGV.size != 1
  puts "Usage: gencr time  15:00 or \"3/4 15:00\""
  exit
end


copyfilesbefore ARGV[0]

Time

Time.local(2008, 3, 5, 11, 20, 00)
# Suppose it is "Thu Nov 29 14:33:20 GMT 2001" now and
# your timezone is GMT:
Time.parse("16:30")     #=> Thu Nov 29 16:30:00 GMT 2001
Time.parse("7/23")      #=> Mon Jul 23 00:00:00 GMT 2001
Time.parse("Aug 31")    #=> Fri Aug 31 00:00:00 GMT 2001

Ruby web test framework

  1. Watir WebDriver

sudo apt-get install curl git-core

bash -s stable < <(curl -s https://raw.github.com/wayneeseguin/rvm/master/binscripts/rvm-installer )

rvm pkg install openssl

rvm install 1.9.3-p125 --with-openssl-dir=$rvm_path/usr

HomePage http://wiki.openqa.org/dashboard.action

http://wtr.rubyforge.org/install.html

http://code.google.com/p/tg4rb/

<#+BEGIN_SRC > require 'rubygems' require 'firewatir' #+END_SRC

You need install firefox plugin too.

Unit test sample code is in the /var/lib/gems/1.8/gems/firewatir-1.6.2/unittests

http://wiki.openqa.org/display/WTR/Tutorial

Cheat Sheet

Getting Started

Load the Watir library 

require 'watir'

Open a browser (default: Internet Explorer) 

browser = Watir::Browser.new

Open Browser at the specified URL 

browser = Watir::Browser.start("http://google.com")

Go to a specified URL 

browser.goto("http://amazon.com")

Close the browser 

browser.close

Browser options (IE only)

Speed up execution (or use the "-b" command line switch) 

browser.speed = :fast

Maximize browser window 

browser.maximize

Pop browser window to front 

browser.bring_to_front

Access an Element

Text box or text area 

t = browser.text_field(:name, "username")

Button 

b = browser.button(:value, "Click Here")

Drop down list 

d = browser.select_list(:name, "month")

Check box 

c = browser.checkbox(:name, "enabled")

Radio button 

r = browser.radio(:name, "payment type")

Form 

f = browser.form(:name, "address")
f = browser.form(:action, "submit")

Link 

l = browser.link(:url, "http://google.com")
l = browser.link(:href, "http://google.com")

Table cell in a table (2nd row, 1st column) 

td = browser.table(:name, 'recent_records')[2][1]

Manipulate the Element

Click a button or link 

b.click
l.click

Enter text in a text box 

t.set("mickey mouse")

Enter multiple lines in a multi-line text box 

t.set("line 1\nline2")

Set radio button or check box 

c.set
r.set

Clear an element 

t.clear
c.clear
r.clear

Select an option in a drop down list 

d.select "cash"
d.set "cash"

Clear a drop down list 

d.clearSelection

Submit a form 

f.submit

Flash any element (useful from the watir-console) 

e.flash

Check the Contents

Return the html of the page or any element 

browser.html
e.html

Return the text of the page or any element 

browser.text
e.text

Return the title of the document 

browser.title

Get text from status bar. 

browser.status
=> "Done"

Return true if the specified text appears on the page 

browser.text.include? 'llama'

Return the contents of a table as an array 

browser.table(:id, 'recent_records').to_a

How do I deal with timing issues and not use sleep?

Sometimes you need to wait for something to happen in the Application under test before you interact with it. Sleep statements are hardcoded and lock you down into a certain number of seconds before moving through your test. To avoid that, we've written a polling mechanism in the latest versions of Watir - the wait_until method.

An example might be that you're loading the Google home page and for some reason it's taking time to load. Here's a basic contrived script with a sleep statement.

require 'watir'

browser = Watir::IE.start('http://www.google.com') sleep 5 # we need to wait for the page to load and on a subjective basis I've chosen 5 seconds which works on my machine browser.text_field(:name, 'q').set('ruby poignant') ....

Unfortunately the sleep is hardcoded and doesn't work for anyone else on my team who have slower network connections, my connection has gotten faster, but it still waits for 5 seconds before setting the text field.

Watir 1.5.x has added a wait_until method that can poll for a certain condition to return true before continuing on or erroring out. By default it checks the condition every half second up until 60 seconds. So I rewrite my code to look like this:

require 'watir'

browser = Watir::IE.start('http://www.google.com') Watir::Waiter.wait_until{ browser.text_field(:name, 'q').exists? } # in this case all I care about is the text field existing, you could check title, text, anything you're

browser.text_field(:name, 'q')set('ruby poignant') ...

It now works for me with a half second delay, but also works for the other members of my team who have network delays up to a minute. If you're considering using sleep, use wait_until instead. It will make your test code more resilient to timing issues in those cases where you really need to use it.

在Cygwin使用Ruby问题

Aug 08

Tech Cheery 1 Comment »

E-texteditor需要cygwin来使用Bundles的功能，在默认的安装的情况下在cygwin中调用ruby会出现 /usr/bin/ruby: no such file to load -- ubygems (LoadError) 的错误提示。n

这是因为cygwin中虽然声明了RUBYOPT环境变量，但是rubygem却并没有安装。 declare -x RUBYOPT="-rubygems"

一种解决方法是使用 unset RUBYOPT 清楚此变量，可以将其写入cygwin的用户profile中。

另一种彻底的解决方法是到rubyforge上下载rubygem然后在cygwin下安装，一劳永逸。

安装方法，解压下载的压缩包，在cygwin下进入其目录，先使用unset RUBYOPT，然后ruby setup.rb 即可完成安装。

Unit Test

<#+BEGIN_SRC >

If we want, we can ask it to run just a particular test method: % ruby test_roman.rb -n test_range Loaded suite test_roman Started . Finished in 0.000600 seconds. 1 tests, 2 assertions, 0 failures, 0 errors, 0 skips or tests whose names match a regular expression: % ruby test_roman.rb -n range Loaded suite test_roman Started . Finished in 0.001036 seconds. 1 tests, 2 assertions, 0 failures, 0 errors, 0 skips

#+END_SRC

创建日期：2013-12-19 修改日期：2015-02-17 ruby Will Chang

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