I have been trying to learn more about the rubygems system in ruby. One curious constant I have encountered is GEM_DEP_FILES. The ruby-doc.org page for Module: Gem has nothing to say about this value other than its name. Here is what I get in irb:
irb(main):002:0> Gem::GEM_DEP_FILES
=> ["gem.deps.rb", "Gemfile", "Isolate"]
Now "Gemfile" is the dependency mechanism we all know and love. I think; At least it is the same name.
My question is what about the others?
A wild guess is that "gem.deps.rb" is some old, obsolete predecessor to "Gemfile"? Maybe?
I have no clue at all about the entry called "Isolate".
I have looked with no success. Can anyone shed any light about these obscure entries?
In case it matters:
20 mysh>ruby --version
ruby 2.3.3p222 (2016-11-21 revision 56859) [i386-mingw32]
21 mysh>gem --version
2.5.2
http://ruby-doc.org/stdlib-2.3.3/libdoc/rubygems/rdoc/Gem.html
I am working to add a utility command to my mysh program that will display pertinent gem related info, so any info, advice, or guidance would be most welcome.
Related
In ~/src/project/ containing all the files, I'm attempting to run bundle and bundle install, but it tells me I need a gem called "buff-extensions" and that gem installer requires Ruby version >= 2.2.0 to work properly.
When I ran ruby --version, it said Ruby 2.2.4p230 is being used when run from that directory.
I know there are several versions of Ruby on the machine in several places, and I'm struggling to follow the paths and figure out which technology is using which piece.
The Bundler docs spell this out:
You can specify the required version of Ruby in the Gemfile with ruby. If the Gemfile is loaded on a different Ruby version, Bundler will raise an exception with an explanation.
ruby '1.9.3'
What this means is that this app has a dependency to a Ruby VM that is ABI compatible with 1.9.3. If the version check does not match, Bundler will raise an exception. This will ensure the running code matches. You can be more specific with the :engine and :engine_version options.
ruby '1.9.3', :engine => 'jruby', :engine_version => '1.6.7'
I finally figured out the exact incantation in order to get the intended result, and I now realize the situation is unreasonable to expect any stranger to attempt to answer.
It involved chef, and I was supposed to run chef exec bundle.
I'm new to Ruby and I'm having a lot of trouble trying to use Nokogiri. I've been trying to find a resolution for hours now, so any help is appreciated. I tried searching for and using solutions from other related SO posts before caving and posting my own. When I run ruby -v I get: ruby 1.8.7 (2011-06-30 patchlevel 352) [x86_64-linux]
(Edit: I have updated ruby with updates-alternatives --config ruby and selected /usr/bin/ruby1.9.1 but when I do ruby -v it is now showing version 1.9.3 WTF am I doing wrong here?)
I have a new project directory at ~/workspace/ruby/rubycrawler/ and I used Bundler to install nokogiri, which installed correctly:
Using mini_portile (0.5.2)
Using nokogiri (1.6.1)
Using bundler (1.5.1)
Your bundle is complete!
Running bundle show nokogiri returns /var/lib/gems/1.9.1/gems/nokogiri-1.6.1.
In the directory I'm running the script from I have a simple html file named "index.html". The script I'm trying to run is even simpler (or so I thought):
require 'nokogiri'
page = Nokogiri::HTML(open("index.html"))
puts page.class # Nokogiri::HTML::Document
The error is rubycrawler.rb:1:in 'require': no such file to load -- nokogiri (LoadError).
I also added require 'rubygems' even though I read it isn't needed for 1.9+ and still no luck.
A lot of searching shows "Did you put this gem in your Gemfile?". So I generate a Gemfile and add gem 'nokogiri'. I try running the small script again and get the same error. I read "Try deleting Gemfile.lock." so I did but still couldn't get it to work. I then read to try testing it out in irb so I tested "open-uri" and "nokogiri" and here's what I got:
irb(main):001:0> require 'open-uri'
=> true
irb(main):003:0> require 'nokogiri'
LoadError: no such file to load -- nokogiri
I'm really having a lot of trouble figuring this out, so really any help at all is really appreciated.
Ruby tools like RVM, Bundler, etc., to the novice, appear to do a lot of magic, but really, there is no magic to them. The key here lies in what Bundler actually does for you. It manages a manifest of dependencies, BUT at runtime, those dependencies STILL have to get loaded somehow, and my gut feeling is that is what is not happening here.
Regardless of what version of Ruby you are using, if you are using Bundler, there's an easy way to do this. Precede the command that starts your program with "bundle exec" and that will make Bundler edit Ruby's load path so that it includes all the things in the manifest (Gemfile.lock).
For example:
$ bundle exec ruby foo.rb
A additional note for anyone using RVM: RVM generally will modify the shebangs in the scripts that launch programs like "ruby" or "rake" so that they use the "ruby_no_exec" shell (or similar) instead of the plain old "ruby" shell. That alternate shell is Bundler-aware and makes it generally unnecessary to type "bundle exec," but since the OP is using system Ruby, that's not applicable and commands should be manually prefixed with "bundle exec".
Hope this helps!
In addition to Kent's answer, I would recommend switching to RVM instead of using the system installed ruby. System rubies tend to be horribly out of date, especially when it comes to important things like features and security updates. It might not help you in your current situation, but it would be well worth the time. If you are unfamiliar: http://rvm.io
I know it's possible to get the Ruby version (e.g. "1.9.3") via the RUBY_VERSION constant. However, I want to know how to go about determining the exact version (e.g.: "1.9.3-p0"). The reason is that there is a bug that was not fixed in earlier versions of Ruby 1.9.3 that is working in later versions, and I want some code in a gem I'm working on to account for this.
There is a RUBY_PATCHLEVEL constant as well. So you can get your version string as
"#{RUBY_VERSION}-p#{RUBY_PATCHLEVEL}"
At least in the newest Ruby (2.3.0), there is also a RUBY_DESCRIPTION constant:
RUBY_DESCRIPTION
# => "ruby 2.3.0p0 (2015-12-25 revision 53290) [x86_64-linux]"
-- UPDATE --
Ok its fixed. This is what I did. remove all ruby and rubygems completely. then install ruby1.9.1-full and rubygems1.9.1 then install the twitter gem.
Hi guys,
I am having trouble working with the Twitter gem. I am using ruby 1.8.7
After installing when I try to run a simple script I get this error
ruby twitter.rb
./twitter.rb:5: uninitialized constant Twitter (NameError)
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:31:in gem_original_require'
from /usr/lib/ruby/1.8/rubygems/custom_require.rb:31:inrequire'
from twitter.rb:2
I running this on a Ubuntu box. I checked with gem -list and I see the Twitter (1.1.0) is listed there.
this is the code I am trying to run
require "rubygems"
require 'twitter'
puts Twitter.user_timeline("test").first.text
Any ideas ?
I believe it only works with Ruby 1.9 If you want to use twitter gem try version 0.9 with Ruby 1.8.x
This works for me:
ruby-1.9.2-p0 > require 'twitter'
=> true
ruby-1.9.2-p0 > puts Twitter.user_timeline("test").first.text
TExES Pedagogy and Professional Responsibilities EC-12 Teacher Certification Test Prep Study Guid… - by Sharon A Wynne http://amzn.to/f3kF74
=> nil
which version of ruby are you using?
gouravtiwari21's comment seems to fix the problem, but it's wrong to suggest that the twitter gem requires 0.9.0 if you want to run it using Ruby 1.8.x.
You can check out the version compatibility here:
http://travis-ci.org/#!/jnunemaker/twitter
It shows the twitter gem working with Ruby installs as low as 1.8.7.
For me, it was an issue with having the correct dependent gems, as well as the correct versions.
Here's how I got it working:
I ran:
sudo gem list
And compared the versions of specific gems with what I found here:
https://github.com/jnunemaker/twitter/blob/master/HISTORY.md (I simply searched for the word 'dependency' to see which versions twitter cared about.
I also found this diff:
https://github.com/jnunemaker/twitter/commit/ac8114c1f6ba2da20c2267d3133252c2ffc6b6a3
And I compared the gems listed there with what I had installed, and I just made sure my system lined up with what I was seeing in the version notes. Oftentimes what happened is that I had multiple versions of a gem, and for some reason, the lower version was taking precedence.
I'm not sure why I still have to add
gem 'twitter', '1.7.1'
to my Gemfile, but alas, that's the last step required in order to get this stuff working.
Don't forget to restart your server, and you should be good!
I'm using Ruby 1.9.2 (Yarv).
When I install gems I just use "gem install ".
How can I know which Ruby version they are written in: 1.8.7, 1.9.1 or 1.9.2?
If I'm using the latest version and I install a gem that is written in 1.8.7, then that gem doesn't work?
Eg. Yardstick gem seems to not work with 1.9.2 but perfectly with 1.8.7.
How do you check what version each gem is using?
Could someone enlighten this topic for me.
Unfortunatelly there is no definitive way to check that as there are so many versions and variants or Ruby interpreters (Ruby, JRuby, Iron Ruby) and system platforms. Also one gem which is pure Ruby may not work on all platforms with same interpereter verson, because some OS specific properties could be used.
So you must trust the autor or docs he/she provided. Another way to make sure that your platform is right for gem just run tests enclosed to gem - every well written gem should have such.
There is also small tip: if file contains
# -*- encoding: utf-8 -*-
then autor probably developed the gem with 1.9.x in mind.
There's a website for answering the question: "Is it Ruby 1.9?"
http://isitruby19.com/
It doesn't look like anyone has reported on Yardstick yet:
http://isitruby19.com/yardstick
You could be the first, and report that it's broken in 1.9.