Can't install Nokogiri for Ruby in Windows

Question

I know this is simple but I just can't figure it out. I need to run a script in Ruby and it requires Nokogiri. I do have some experience in other languages but not in Ruby.

Here is my system :

Ruby 2.0.0-p195 (x64) is installed @ C:\Programs\RubyLanguage

Ruby Development Kit (mingw64-64-4.7.2-20130224-1432) is installed @ C:\Programs\RubyDevKit

When I run gem install nokogiri I get this error:

    ERROR:  Error installing nokogiri:
        The 'nokogiri' native gem requires installed build tools.

Please update your PATH to include build tools or download the DevKit
from 'http://rubyinstaller.org/downloads' and follow the instructions
at 'http://github.com/oneclick/rubyinstaller/wiki/Development-Kit'

Easy enough. So I followed the link of above and did to step 3. However step 4 says generate "config.yml". So I did. Now the file is an empty list with some comments. I still can't install Nokogiri because of error above and I don't seem to get anywhere with DevKit . What I am saying is that the steps in the Development Kit installation is not clear enough for me.

---

Update it now says installation of Nokogiri failed ( DevKit Works according to step 5 : Installing documentation for json-1.8.0 1 gem installed )

mkmf.log: package configuration for libxslt is not found
package configuration for libxml-2.0 is not found
package configuration for libiconv is not found
find_header: checking for libxml/parser.h... -------------------- no

"x86_64-w64-mingw32-gcc -o conftest.exe -IC:/Programs/RubyLanguage/include/ruby-2.0.0/x64-mingw32 -IC:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/backward -IC:/Programs/RubyLanguage/include/ruby-2.0.0 -I. -IC:/Programs/RubyLanguage/include/libxml2 -IC:/Programs/RubyLanguage/include -DFD_SETSIZE=2048 -D_WIN32_WINNT=0x0501 -D_FILE_OFFSET_BITS=64   -O3 -fno-omit-frame-pointer -fno-fast-math -g -Wall -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Wunused-variable -Wpointer-arith -Wwrite-strings -Wdeclaration-after-statement -Wimplicit-function-declaration  -DXP_WIN -DXP_WIN32 -DUSE_INCLUDED_VASPRINTF -O3 -Wall -Wcast-qual -Wwrite-strings -Wconversion -Wmissing-noreturn -Winline conftest.c  -L. -LC:/Programs/RubyLanguage/lib -LC:/Programs/RubyLanguage/lib -L.      -lx64-msvcrt-ruby200  -lshell32 -lws2_32 -limagehlp -lshlwapi   "
In file included from C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/defines.h:153:0,
                 from C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/ruby.h:70,
                 from C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby.h:33,
                 from conftest.c:1:
C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/win32.h: In function 'rb_w32_pow':
C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/win32.h:776:16: warning: conversion to 'double' from 'long double' may alter its value [-Wconversion]
In file included from C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby.h:33:0,
                 from conftest.c:1:
C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/ruby.h: In function 'rb_float_value':
C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/ruby.h:777:6: warning: negative integer implicitly converted to unsigned type [-Wsign-conversion]
C:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/ruby.h:777:6: warning: negative integer implicitly converted to unsigned type [-Wsign-conversion]
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <winsock2.h>
4: #include <windows.h>
5: int main(int argc, char **argv)
6: {
7:   return 0;
8: }
/* end */

"x86_64-w64-mingw32-gcc -E -IC:/Programs/RubyLanguage/include/ruby-2.0.0/x64-mingw32 -IC:/Programs/RubyLanguage/include/ruby-2.0.0/ruby/backward -IC:/Programs/RubyLanguage/include/ruby-2.0.0 -I. -IC:/Programs/RubyLanguage/include/libxml2 -IC:/Programs/RubyLanguage/include -DFD_SETSIZE=2048 -D_WIN32_WINNT=0x0501 -D_FILE_OFFSET_BITS=64   -O3 -fno-omit-frame-pointer -fno-fast-math -g -Wall -Wextra -Wno-unused-parameter -Wno-parentheses -Wno-long-long -Wno-missing-field-initializers -Wunused-variable -Wpointer-arith -Wwrite-strings -Wdeclaration-after-statement -Wimplicit-function-declaration  -DXP_WIN -DXP_WIN32 -DUSE_INCLUDED_VASPRINTF -O3 -Wall -Wcast-qual -Wwrite-strings -Wconversion -Wmissing-noreturn -Winline  conftest.c -o conftest.i"
conftest.c:5:27: fatal error: libxml/parser.h: No such file or directory
compilation terminated.
checked program was:
/* begin */
1: #include "ruby.h"
2: 
3: #include <winsock2.h>
4: #include <windows.h>
5: #include <libxml/parser.h>
/* end */

CMD log

Microsoft Windows [Version 6.1.7601]
Copyright (c) 2009 Microsoft Corporation.  All rights reserved.

C:\Users\SEPEHR>gem install nokogiri
Temporarily enhancing PATH to include DevKit...
Building native extensions.  This could take a while...
ERROR:  Error installing nokogiri:
        ERROR: Failed to build gem native extension.

    C:/Programs/RubyLanguage/bin/ruby.exe extconf.rb
checking for libxml/parser.h... no
-----
libxml2 is missing.  please visit http://nokogiri.org/tutorials/installing_nokog
iri.html for help with installing dependencies.
-----
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers.  Check the mkmf.log file for more details.  You may
need configuration options.

Provided configuration options:
        --with-opt-dir
        --without-opt-dir
        --with-opt-include
        --without-opt-include=${opt-dir}/include
        --with-opt-lib
        --without-opt-lib=${opt-dir}/lib
        --with-make-prog
        --without-make-prog
        --srcdir=.
        --curdir
        --ruby=C:/Programs/RubyLanguage/bin/ruby
        --with-zlib-dir
        --without-zlib-dir
        --with-zlib-include
        --without-zlib-include=${zlib-dir}/include
        --with-zlib-lib
        --without-zlib-lib=${zlib-dir}/lib
        --with-iconv-dir
        --without-iconv-dir
        --with-iconv-include
        --without-iconv-include=${iconv-dir}/include
        --with-iconv-lib
        --without-iconv-lib=${iconv-dir}/lib
        --with-xml2-dir
        --without-xml2-dir
        --with-xml2-include
        --without-xml2-include=${xml2-dir}/include
        --with-xml2-lib
        --without-xml2-lib=${xml2-dir}/lib
        --with-xslt-dir
        --without-xslt-dir
        --with-xslt-include
        --without-xslt-include=${xslt-dir}/include
        --with-xslt-lib
        --without-xslt-lib=${xslt-dir}/lib
        --with-libxslt-config
        --without-libxslt-config
        --with-pkg-config
        --without-pkg-config
        --with-libxml-2.0-config
        --without-libxml-2.0-config
        --with-pkg-config
        --without-pkg-config
        --with-libiconv-config
        --without-libiconv-config
        --with-pkg-config
        --without-pkg-config


Gem files will remain installed in C:/Programs/RubyLanguage/lib/ruby/gems/2.0.0/
gems/nokogiri-1.6.0 for inspection.
Results logged to C:/Programs/RubyLanguage/lib/ruby/gems/2.0.0/gems/nokogiri-1.6
.0/ext/nokogiri/gem_make.out

Answer 1

Update: As of version 1.6.2, Nokogiri now does support the 64-bit version of Ruby 2.0.0. (Note that it requires libxml >= 2.6.21 )

Here's the answer if you still need to install the x86 version for some reason or if you want to understand how to install and build a gem using DevKit:

---

Nokogiri does not yet support the 64-bit version of Ruby 2.0.0. You can read about it and follow the status here.

But Nokogiri does support the x86 version of ruby 2.0.0. You should be able to install the gem in on 2.0.0 x86 install.

It's pretty easy to hand-install. I prefer that over RailsInstaller because I need to maintain other things as they are. Here's how:

1. Download and unzip the files for the version you need. Be sure to download the correct version of DevKit for the x86 version of 2.0.0.

2. Fix your path: Make sure your path includes the directories to the right ruby, gem, and DevKit dirs: Assume you installed the x86 version of ruby 2.0.0 into C:\rubies\ruby-2-0-0-x86 and the associated DevKit into C:\rubies\DevKit-xxxx-x86 you will need to include these directories in your PATH:

   C:\rubies\ruby-2-0-0-x86\bin C:\rubies\ruby-2-0-0-x86\lib\ruby\gems\2.0.0 C:\rubies\DevKit-xxxx-x86\bin

3. Inject DevKit into the right ruby install: Once you have ruby installed and can get the correct info when you type ruby -v, then run ruby dk.rb init -- which will get DevKit set up & 'injected' into the correct ruby version. (N.B. I always have to edit the config.yml file that is produced and put in the correct path to the ruby installation I want. Don't sweat it if you need to do that.)