Ruby Projects Ruby Projects and and

LibrariesLibraries

Vorleak Chy (vorleak.chy@gmail.com)Vorleak Chy (vorleak.chy@gmail.com)

Software EngineerSoftware Engineer

Yoolk IncYoolk Inchttp://groups.google.com/group/khmertech/http://groups.google.com/group/khmertech/

AgendaAgenda

Projects and Using Code from Projects and Using Code from Other FilesOther Files

LibrariesLibraries

RubyGemsRubyGems

IntroductionIntroduction

Using code already written and Using code already written and prepared by other developers prepared by other developers within your own applicationswithin your own applications

Projects and Using Projects and Using Code from Other FilesCode from Other Files

Basic File InclusionBasic File Inclusion

Inclusions from Other DirectoriesInclusions from Other Directories

Logic and Including CodeLogic and Including Code

Nested InclusionsNested Inclusions

Basic File InclusionBasic File InclusionUses the Uses the require require or or loadload command command to load the external file into the to load the external file into the current programcurrent program

#file: string_extensions.rb#file: string_extensions.rbclass Stringclass String def vowelsdef vowels self.scan(/[aeiou]/i)self.scan(/[aeiou]/i) endendendend

#file: vowel_test.rb#file: vowel_test.rbrequire 'string_extensions'require 'string_extensions'puts "This is a test".vowels.join('-')puts "This is a test".vowels.join('-')

Basic File Inclusion Basic File Inclusion (Cont.)(Cont.)Ruby programmers generally use Ruby programmers generally use requirerequire rather than rather than loadload. The effects . The effects of of loadload are only useful if the code in are only useful if the code in the external file has changed or if it the external file has changed or if it contains active code that will be contains active code that will be executed immediatelyexecuted immediately

#file: b.rb#file: b.rbload 'a'load 'a'puts "Hello from b.rb"puts "Hello from b.rb"load 'a'load 'a'puts "Hello again from b.rb"puts "Hello again from b.rb"

#result output#result outputHello from a.rbHello from a.rbHello from b.rbHello from b.rbHello from a.rbHello from a.rbHello again from b.rbHello again from b.rb

#file: a.rbputs "Hello from a.rb"

Inclusions from Other Inclusions from Other DirectoriesDirectoriesThe process of The process of requirerequire and and loadload

First looks the file in the current First looks the file in the current folderfolder

Second looks the file in the various Second looks the file in the various folders where Ruby stores its own folders where Ruby stores its own file and librariesfile and libraries

Lists of directories to search for Lists of directories to search for included files in a special variable included files in a special variable called $:.called $:.$:.each { |d| puts d }

/usr/local/lib/ruby/site_ruby/1.8/usr/local/lib/ruby/site_ruby/1.8/i686-darwin8.8.1/usr/local/lib/ruby/site_ruby...

Inclusions from Other Inclusions from Other Directories (Cont.)Directories (Cont.)Adds extra folders to search the fileAdds extra folders to search the file

$: is an array, so you can push extra $: is an array, so you can push extra items to ititems to it

$:.push '/your/directory/here'require 'yourfile'

Logic and Including Logic and Including CodeCodeAdds logic to the Adds logic to the require require oror load load commandcommand

$debug_mode = 0require $debug_mode == 0 ? "normal-classes" : "debug-classes"

%w{file1 file2 file3 file4 file5}.each { |l| require l }

Nested InclusionsNested InclusionsCode from files that are included into others Code from files that are included into others with with requirerequire and and loadload has the same freedom has the same freedom as if the code were pasted directly into the as if the code were pasted directly into the original file.original file.#file: a.rbrequire 'b' #And b.rb contains the following:require 'c' #And c.rb contains the following:def example puts "Hello!"end

#And d.rb contains the following:require 'a'example

LibrariesLibrariesCollection of routines that can be Collection of routines that can be called by separate programs, but called by separate programs, but that exist independently of those that exist independently of those programs.programs.

A list of all the standard libraries, A list of all the standard libraries, including documentation, is including documentation, is available at http://www.ruby-available at http://www.ruby-doc.org/stdlib/doc.org/stdlib/

How to use two standard librariesHow to use two standard libraries

net/http Librarynet/http LibraryHTTP stands for HyperText Transfer Protocol, HTTP stands for HyperText Transfer Protocol, and it’s the main protocol that makes the and it’s the main protocol that makes the World Wide Web work, as it provides the World Wide Web work, as it provides the mechanism by which Web pages, files, and mechanism by which Web pages, files, and other media can be sent between Web other media can be sent between Web servers and clientsservers and clientsrequire 'net/http'Net::HTTP.get_print('www.rubyinside.com', '/')

require 'net/http'url = URI.parse('http://www.rubyinside.com/')response = Net::HTTP.start(url.host, url.port) do |http| http.get(url.path)endcontent = response.body

OpenStruct LibraryOpenStruct LibraryMore flexible than StructMore flexible than Struct

Creates data objects without Creates data objects without specifying the attributesspecifying the attributes

Create attributes on the flyCreate attributes on the fly

#structPerson = Struct.new(:name, :age)me = Person.new("Fred Bloggs", 25)me.age += 1

#openStructrequire 'ostruct'person = OpenStruct.newperson.name = "Fred Bloggs"person.age = 25

RubyGemsRubyGemsPackaging system for Ruby Packaging system for Ruby programs and libraries.programs and libraries.

Manages different versions of the Manages different versions of the same libraries on your PCsame libraries on your PC

Installing RubyGemsInstalling RubyGemsBefore you can use RubyGems, it’s Before you can use RubyGems, it’s necessary to install itnecessary to install it

On Windows, if you installed Ruby On Windows, if you installed Ruby using the “one-click installer”, you using the “one-click installer”, you already have RubyGem installedalready have RubyGem installed

On Mac OS X, Linux, and Other Unix On Mac OS X, Linux, and Other Unix

After you installed you can type After you installed you can type gemgem

Finding GemsFinding GemsLists of the gems that are installed Lists of the gems that are installed

gem list

Queries the remote gem serverQueries the remote gem server

gem list --remote

gem query --remote --name-matches class

Queries the remote gem server Queries the remote gem server and match the name “class”and match the name “class”

Installing a Simple GemInstalling a Simple GemInstalls “feedtools”Installs “feedtools”

gem install feedtools

#if it can't install probablysudo gem install feedtools

Using GemsUsing GemsRubyGems system isn’t an RubyGems system isn’t an integrated part of Rubyintegrated part of Ruby

It’s necessary to tell your It’s necessary to tell your programs that you want to use programs that you want to use and load gemsand load gems

require 'rubygems'require 'RedCloth'r = RedCloth.new("this is a *test* of _using RedCloth_")puts r.to_html

Installing a More Installing a More Complex GemComplex GemYou may want to install You may want to install “hpricot” in specific source for “hpricot” in specific source for latest versionlatest versiongem install hpricot --source code.whytheluckystiff.net

Upgrading and Upgrading and Uninstalling GemsUninstalling GemsUpdate all of your currently installed Update all of your currently installed gemsgemsgem update

Uninstall gems “feedtools” Uninstall gems “feedtools”

gem uninstall feedtools

$ gem uninstall rubyforge

Uninstall all gem versions Uninstall all gem versions “rubyforge”“rubyforge”

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