Error installing "nokogiri" in a Ruby on Rails application? - mysql

I've been following along with the Lynda.com's Ruby on Rails course. I did everything just as mentioned inside the videos.
I am trying to run the rails server command, which should default to WEBrick, correct?
I run the command and it has an issue in the nokogiri.rb file and on line 29 where the error is happening this is what is read:
require 'nokogiri/nokogiri'
Which is what my command prompt is throwing up on when running the rails server command. Any idea what could be causing this? If so, what commands do I need to run to settle this? To me it sounds like something was missed when installing MySQL.
I am not sure what nokogiri is and why rails server won't run and points to that line of code.
The path to this file is (Wherever you installed the folder to)\lib\ruby\gems\2.2.0\gems\nokogiri-1.6.6.2-x64-mingw32\lib
EDIT**: I have a chain of errors, like it goes from -long path-, from -longpath- etcetera. I tried installing the latest gem, and it wasn't successful. Is there a log file I can get to share with you guys to help figure out the issue.

nokogiri is a Ruby "gem" (library) for parsing XML and HTML.
Your Rails project should have a Gemfile which specifies the name and version of each gem needed to run the project. To install the gems listed in the gemfile:
bundle install
After that install completes successfully, Rails should be able to find the nokogiri gem.

Try this
$ sudo apt-get install libxslt-dev libxml2-dev zlib1g-dev
$ sudo gem install nokogiri -v '1.5.11'

According to \lib\ruby\gems\2.2.0\gems\nokogiri-1.6.6.2-x64-mingw32\lib, which means that you are running it on Windows platform. You are using ruby 2.2.0.
I know that nokogiri conflicts with 2.2.* versions of ruby in Windows. I have already encountered this problem. I think it is because of mingw32.
You need to install 2.1.* version of Ruby in order to make Nokogiri work.

Related

how can i install jruby alongside ruby

i first installed jruby using the sudo apt-get install jruby command, which succeeded but it did gave me 1.5.6 version when i wanted a later version. So i uninstalled it and used rvm install jruby command and i was able to install jruby version 1.7.19 but after installing it, my ruby applications,which were funtioning right started producing errors complaining of missing gems like mysql2 gem missing,run bundle install. i run bundle install but nothing i did seemed to help, i was getting nowhere.
When i asked for the ruby version, i was receiving the jruby version instead, its lyk jruby over shadowing ruby,,,, So i decided to uninstall jruby, reinstall ruby and now ruby is functioning as well as before.
Can anyone help me with the ubuntu commands which can help me install jruby alongside ruby, so that both work well without any errors???
Am requesting for serious help please
I usually prefer rbenv over rvm for running multiple versions of Ruby on the same machine. Here is sample install/usage steps:
Install rbenv git clone git://github.com/sstephenson/rbenv.git ~/.rbenv
Install ruby-build git clone git://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
Modify your .bashrc echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bashrc
echo 'eval "$(rbenv init -)"' >> ~/.bashrc
Restart your shell
Install rubies. e.g. rbenv install jruby-1.7.20
Rehash (create new rbenv shims. You'll need to run this anytime you install a gem that adds a command) rbenv rehash
You can list the Ruby versions available to install with rbenv install -l
You can set the default global ruby version with rbenv global jruby-1.7.20.
You can also pass "system" instead of an installed Ruby if you want the default to be the OS installed version of Ruby.
You can change Ruby version on the fly with rbenv shell 1.9.3-p551
See here (https://github.com/sstephenson/rbenv#command-reference) for a lot more detail and documentation.
Edit: I was assuming you're using Ubuntu, hence the edit of .bashrc. If you're using another OS you may need to change that to .bash_profile
Thanks for that answer. I have also found out that it is soo possible to have jruby and ruby installed concurrently using rvm. After installing the various versions or languages say ruby and jruby, only the default language and version is running in the terminal as current so you have to run the command 'rvm list' to show you the various installed versions after which you run 'rvm use language-X.X.XX' say rvm use jruby-1.7.20.1 to make jruby-1.7.20.1 run as the current in that terminal.
You can also run another version in a different terminal concurrently but please note, you have to run the command rvm use every time you open up a new terminal, else you make that version default.

Ruby on Rails isn't allowing me to run app through localhost:3000

I'm trying to connect my app to localhost:3000 to try and run ruby on rails but when I put localhost:3000 into browser it downloads a file. So when I kept looking for something to resolve this problem it kept saying to go and do a bundle install and then after it's done it then says error and says try and install 'gem install mysql2 -v 0.3.14 before bundling. So i do that and go and bundle install again and it gives me the same error
the problem seems like bundler cannot install mysql2 gem, thats why bundler says to install it explicitly .
try run gem install mysql2 and see what are the errors you are getting. I'm not sure about windows but in linux the common problem is lack of header files.
and this SO question might also give you some hint..

Installing Rails, MySQL, etc. everything goes wrong

I've been struggling with this for a few hours. Everything just stopped working and I can't get it to work anymore. I'm a noob at Ruby, Ruby on Rails and the Terminal in general. This is really frustrating me so I just try to describe my problem as detailed as possible hoping someone can give me a solution.
I'm on Mac OS X Snow Leopard. I couldn't get Rails working at all just now: Could not find gem 'rails' headaches
But after some tries of reinstalling it, it suddenly worked again. But now I just can't get MySQL to work, and it sometimes even breaks the Rails installation again.
This is what I do:
sudo gem uninstall rails
sudo gem uninstall mysql
sudo gem uninstall mysql2
After these commands, I check the installed gems with gem list. No MySQL gem is listed anymore, but I can still see rails (2.3.5, 2.2.2, 1.2.6)
. Is this normal? Does this mean I have 3 Rails installations? It doesn't make sense to me. Anyway, then I do this:
sudo gem clean
Which fails completely. I get a bunch of errors like this:
Attempting to uninstall fcgi-0.8.7
Unable to uninstall fcgi-0.8.7:
Gem::InstallError: cannot uninstall, check gem list -d fcgi
It doesn't uninstall anything. At this point, I try to install everything again. I start with:
sudo gem install rails
Which succeeds (I think):
Successfully installed rails-3.0.3
Successfully installed builder-2.1.2
2 gems installed
Installing ri documentation for rails-3.0.3...
File not found: lib
Then, I update RubyGems:
sudo gem update --system
sudo gem install rubygems-update
sudo update_rubygems
Then it says I have 1.3.7 installed, so it succeeded, I think. So now I proceed with installing MySQL. I already got MySQL 5.5.8 installed on my machine. I did some research about installing MySQL on Snow Leopard, and it seems I have to use this command:
sudo env ARCHFLAGS="-arch x86_64" gem install mysql -- --with-mysql-config=/usr/local/mysql/bin/mysql_config
I get a bunch of errors like this:
No definition for time_set_neg
No definition for time_set_second_part
No definition for time_equal
No definition for error_errno
At this point, I assume I got both Rails and the MySQL gem installed, so I try to start a new project.
rails new user_group -d mysql
It works! Rails is installed correctly. Now, I try generating a model.
cd user_group
rails generate model User
It fails with this error:
Could not find gem 'mysql2 (>= 0, runtime)' in any of the gem sources listed in your Gemfile.
Try running bundle install.
So I try running bundle install. It installs a lot of gems. Then I try to generate my model again. I get this error:
Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle: dlopen(/Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle, 9): Library not loaded: libmysqlclient.16.dylib (LoadError)
Referenced from: /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle
Reason: image not found - /Library/Ruby/Gems/1.8/gems/mysql2-0.2.6/lib/mysql2/mysql2.bundle
This is as far as I can get. What should I do? And why should this be so hard...
Snow Leopard supplies Ruby 1.8.7. Ruby 1.8.7 doesn't automatically add the require 'rubygems' command to a Ruby script, like 1.9.2 will, so in general you need to add that to your script. That fixes the problems with Ruby not finding the gems called by your code in a lot of cases. Rails is a different animal, but the version with 1.8.7 is well documented so you should have found a fix pretty quickly.
The Ruby supplied by Snow Leopard is really for its own use. Users can piggyback on that, but it's installed by Apple because they have applications that use it. Use locate podcast | grep rb$ to see. Similarly, Perl and Python in Snow Leopard are used to support code Apple has installed so messing with them is not a good idea. Changing the built-in Ruby, Perl or Python usually won't cause the system to explode in flames, but it can cause irritating and unexplained problems farther down the road when system maintenance routines stop working.
By using sudo to remove gems installed by Apple and add new ones, you've left your system Ruby in an unexpected state as far as Apple's apps are concerned. Rather than mess with Apple's Ruby, you should install a separate Ruby for your own use using Fink or MacPorts, or from source code, or by using RVM.
Personally, I use RVM because it creates a ~/.rvm sandbox in your home directory, and makes it easy to manage multiple versions of Ruby and gems. RVM requires you to install the XCode development library, which you can download from http://developer.apple.com/technologies/ after a free registration. XCode is also on your system DVD, but that version is reported to be buggy, so use the downloaded version.
Make sure to add the MySql gem to that projects gemfile with the following code:
gem 'mysql', '2.8.1'
Run a bundle install/update and try it. You told it to use MySQL and the gem might even be installed, but you aren't loading it.
Also, you're failing at a couple of points: notice the
File not found: lib
Then again, I could be completely wrong about this - it's my attempt at providing a clue for your troubleshooting.

Rails 3 Mysql Problems

Trying to start a new Rails 3 beta 4 app with mysql.... Running OS X Snow Leopard. WIth previous versions of Rails I have no problem with MySQL. But now when I start the Rails 3 app I get the following error when I click "About Your Application Environment" on the Rails index.html startup screen:
undefined method `init' for Mysql:Class
Change your Gemfile to use 'mysql2', it's a more modern driver and has nicer features as other people have mentioned.
New Rails applications use the mysql2 gem by default.
I ran into the same issue (RoR 3, OSX 10.6, mysql 2.8.1 gem).
You can use irb to rule out RoR:
irb
require 'rubygems'
require 'mysql'
db = Mysql.connect('hostname', 'username', 'password', 'database')
If the above doesn't work, you may want to try removing the mysql gem and reinstalling it. I came across a post saying bundle install might mess up the install without displaying errors.
sudo gem uninstall mysql
sudo env ARCHFLAGS="-arch x86_64" gem install mysql -- --with-mysql-config=/usr/local/mysql/bin/mysql_config
Verify things work via irb, then start up rails again.
I ended up switching from the mysql gem to the ruby-mysql gem, worked.
For simple usage, which is typical (connecting, querying, iterating over results), I found mysql2 gem which is much faster than mysql or ruby-mysql gems and auto-casts values to proper types. And it installes perfectly on Snow Leopard while I couldn't get mysql gem to work.
More info at http://github.com/brianmario/mysql2
I think I have found the solution for the problem. In my case the problem was that the mysql gem hasn't been properly installed using the bundler . when I did this:
bundle install mysql (noobish mistake)
all gems went to mysql directory, but later on I have checked the docs of the bundler gem
and did this:
bundle install bundler_files ( to know where the gems are in the future)
everything looked almost ok except that when mysql gem was installing i got some errors.
I noticed that it was because of my folder path "/home/pawel/Aptana Studio Workspace/myrails_app"
If you have spaces in your folder path this gem wont install properly and later on when you modify the path to one without spaces and try to install the mysql gem IT WONT DISPLAY ANY ERRORS, but the installation will be corrupted, because you will have some extra folders there with some files etc. so
DELETE THE GEM FOLDER CREATED BY BUNDLER AND REINSTALL GEMS WITH THIS COMMAND:
bundle install
That solved the problem.
you can try switching to the mysql2 gem which should resolve all that issues for you. see: https://github.com/brianmario/mysql2/
I think what happens is that the mysql gem isn't able to load the mysql dynamic library (supposed to be supplied by the native MySQL installation). To test whether this is happening, do this
$ irb
1.9.2p320 :001 > require 'mysql_api'
=> true
1.9.2p320 :002 >
If it isn't able to load this low level mysql_api, (which actually supplies the functionality to the mysql gem), it will give you some potentially useful errors. Usually it is not able to find the dynamic library. To remedy this, I found a couple of solutions:
From http://wonko.com/post/how-to-install-the-mysqlruby-gem-on-mac-os-x-leopard, do this
For system-wide install
sudo env ARCHFLAGS="-arch i386" gem install mysql -- \
--with-mysql-dir=/usr/local/mysql --with-mysql-lib=/usr/local/mysql/lib \
--with-mysql-include=/usr/local/mysql/include
or local install
env ARCHFLAGS="-arch i386" gem install mysql -- \
--with-mysql-dir=/usr/local/mysql --with-mysql-lib=/usr/local/mysql/lib \
--with-mysql-include=/usr/local/mysql/include
and then from http://alexbraunstein.com/2011/08/12/library-loaded-libmysqlclient-18-dylib/ put in .bash_profile:
export DYLD_LIBRARY_PATH=/usr/local/mysql/lib:$DYLD_LIBRARY_PATH
I has the same issue after upgrading to Snow Leopard. On installing the MySQL gem, I got a bunch of errors about the documentation, then, on running the server:
undefined method `init' for Mysql:Class
I was also having some similar, but unrelated issues with other gems, particularly those that had C components that needed compiling such as RedCloth and hpricot:
Unable to compile native extensions
These errors were to do with native extensions in base 64 architecture. The solution was threefold:
I reinstalled XCode 4. The upgrade to Snow Leopard had broken my C compiler, so some gems were failing to compile. This took me a step closer, but didn't fix the issue.
I blew away and reinstalled RVM. It appeared to be installing gems in one directory, and finding them in another. This fixed every native architecture base64 error, but the MySQL gem was still failing.
I removed and downgraded MySQL to version 5.1. This fixed the MySQL gem issue.
All is now well again.

problems with mysql for ruby on rails

ah...it is not easy to get started ruby on rails to me..
I am trying to use mysql for ruby on rails development.
When I execute "gem install mysql", I get following error.
error: while generating documentation for mysql-2.8.3-x86-mswin32...message: unhandled special: special: type=17...bla bla...
how do I install mysql for ruby on rails!??!
If you are on windows and want to avoid mysql issues, just use v 2.1.2, just before they removed the mysql connector and put it into the mysql gem. It's better like that, but I ran into MANY issues installing this on the Windows XP machine at my work.
Make sure that your version of gems is the latest.
You should be able to update it using:
gem update --system
Going by your error it failed to generate the documentation for the Gem, though it could have installed it as it was. Firstly check to see if it did install, use:
gem list --local
And check to see if the MySQL driver is in the list already.
If it isn't the make sure you're installing the correct version of the driver, either mswin32, or ruby should do.
That's an error concerning rdoc generation. If you execute the following command you'll get no error:
gem install --no-rdoc mysql
I believe there are some problems generating rdoc for the Japanese localized version of the docs. Anyway, the mysql gem gets installed.
You can easily install the MySQL gem
either install the MySQL in ruby file where all gems are install or you can follow the path:
C:\Ruby192\lib\ruby\gems\1.9.1\gems
execute the below command:
gem install MySQL
hope this helps you!