When trying to install a ruby app via bundler, how does your system decide which version of Ruby to use?
Will I run into problems if i use a version of Ruby installed in a directory I do not have access to? If so, how do I ensure I use a version of Ruby installed in the correct directory.
For those voting to close, I am not looking for debugging help. I am looking for an understanding of how bundler decides which version of Ruby to use.
If your app has a Gemfile (most will) you can specify ruby version on Gemfile.
See this question Set ruby version in Gemfile
Related
I am trying to make an CLI tool with ruby.
My tool require some library in bundle (log4r, ...). So problem appear when i switch my ruby version (2.0.0 -> 2.1.2) or when switch gemset, some gem are not install in new ruby environment.
So how can i make my app work like vagrant, which work in every version of ruby i am using?
If you package your application as a Gem, you can include a Gemspec that describes your application. One of the things you can specify is its runtime dependencies; when the user runs gem install myapp, then the gem command will make sure it includes everything you specified (like log4r).
It will be harder to make this happen without Rubygems. You can package your application along with a defined version of Ruby and all its requirements - that's what Vagrant does - but that makes your application a larger download and means you have more to maintain. It's going to be hard work if you want to install your app system-wide and have it work with every single Ruby environment. It's far better to let the gem application install your app (whether systemwide, or via rbenv/rvm) and let that manage your dependencies for you. There's the default gems plugin for rbenv and rvm gemsets to help manage this.
I have multiple Rails apps from 3.2.14 to 3.2.18 in my development environment. I'm using Ruby 1.9.3 (yes, I know) for these apps and it's installed and managed via rbenv. I'm about to build a couple of new apps with Rails 4.1 and Ruby 2.1. My question is, what is the best way to handle installing multiple versions of Ruby using rbenv. Currently 1.9.3 is set to global, but I want different Rails apps (4.1) to use Ruby 2.1.
I guess I'm a bit behind the curve with Ruby management so I could use a hand here. Again, looking to have multiple Rails apps (different versions 3.2.14-4.1.x) and multiple Ruby instances to support each app.
I appreciate the help in advance.
Create a .ruby-version file in your application root directory and specify the ruby version you want. For instance, if you want one application to use 1.9.3 and the other 2.1.0, you'll have a .ruby-version file each in those two applications, specifying the version:
/application1/.ruby-version
1.9.3
/application2/.ruby-version
2.1.0
Update
For every installed version of ruby, you'll have a shims directory which will house all your gems for that particular version. When you switch between ruby versions, rbenv will simply set the environment variables to the one you select.
In the example above, I set the local ruby version for the directory ruby_cookbook to 2.1.2 and a gem list will only show gems installed for 2.1.2.
I also created a .ruby-version with ruby version 1.9.3-p547 in my try_stuff directory. As you can see, gem list only shows gems installed for 1.9.3.
The gems you install are specific to the current version of ruby.
If your project root has a .ruby-version file, your environment will automatically set the current ruby version to the one specified. So, yes, your production environment will need the version you mention in your .ruby-version. If you use git for source control, you can add that file to your .git-ignore and you won't see it in your prod version.
Apologies for the topic title, couldn't resist.
Basically, For no reason whatsoever apart from trying out different things. I want to implode RVM and try out rbenv. Nothing against RVM, just want to try different peoples software and try different things out.
I can get rid of RVM and install rbenv no problem. Could you guys confirm a few things for me.
Firstly, if I do the above, and then install a few different ruby versions. I know I can place a .ruby-version file in a projects root directory to specify a specific ruby version but then when I say gem install <gemname> I take it that is installed globally for that ruby version.
If I then use bundler per project to manage what gems are used and I specify a gem version, what happens if the version specified in the lock file is different to the currently installed version and what happens if it's vice versa?
I just need a bit of clarification on what's doing what in regards to ruby, versions, gems and their versions.
One of the (many) lovely things about rbenv is that you can so easily look right at your ruby installation to see what's going on. For example, on my machine I can open ~/.rbenv and there's versions containing my ruby installations, such as 1.9.3-p327. Opening that, I can keep drilling down to see my gems installed for that version of ruby (in ~/.rbenv/versions/1.9.3-p327/lib/ruby/gems/1.9.1/gems). It is then trivial to run gem list or gem install somegem and confirm that what's being affected is this very collection of gems - if this is the current ruby (set in rbenv global and starred in rbenv versions).
In short, everything about your system thinks that ruby means this version of ruby and that its library is this library.
For Bundler, you'll need to install rbenv-bundler. A nice tutorial (easily found with Google) is here: http://dan.carley.co/blog/2012/02/07/rbenv-and-bundler/
Does every gem have its own rake? Because I was doing android development and I created app using the z$ rhogen app z. and then i did $rake run:android and the android emulator came up. But when I create an app using $rhosync app <appname> then migrate to the root of the app folder and do $rake:dtach install then the rake uses my older version of Ruby 1.8 where as my new and active Ruby version is Ruby 1.9.2. I dont know where to change the config file of the app or gem I am not sure to make Ruby 1.9.2 as my default ruby when I do $rake dtach:install.
As Alex said, rake tasks are not needed in order to have a gem.
What environment are you working on? RVM is a nice way to manage you ruby environments and manage multiple versions of ruby on unix based systems (OS X/ubuntu/debian). Have a look here http://beginrescueend.com/
No, not all gems have rake tasks.
I'm trying to install bdb on Ubuntu as a gem as follows,
gem install bdb
I'm not using sudo, since I am installing with rvm. The ruby version on my system is 1.9.1 but the version I'm using for this installation is 1.8.7 (I'm installing rbot, you see). The problem I've encountered is:
checking for db_version() in -ldb-4.something... no
I assume this means that rubygems is not finding ldb4.something in the places it is looking. Is this because I installed libdb-4.something (7, actually) using sudo, and my system's ruby version is different from the ruby version I'm using for bdb? Using rvm, how should I manage this sort of situation? Maybe I'm doing things wrong, but it seems to me that my problem is that not everything I'm using is a gem, and the stuff that isn't gems is seeing the wrong version of ruby.
(if it turns out that my problem is something completely unrelated: I am still interested in the question. How do things I've installed on my system with a particular version of ruby get along with gems installed using rvm under different versions of ruby?)
"How do things I've installed on my system with a particular version of ruby get along with gems installed using RVM under different versions of ruby?"
They don't, and that is the point. RVM is for managing different versions of Ruby so that they are isolated from each other.
This means that the Ruby versions that you use for system (when you do sudo gem install that would be installing to system) have nothing to do with the current environment (when properly set up.)
When you are in a RVM environment, each version of Ruby installed is an isolated environment.
What I would recommend is this:
Go to the RVM Website and check it out.
At the end of the page, continue with your reading about how to use gemsets.
go to your project directory
rvm use 1.8.7#your_project_environment
create your .rvrmc file so that you will automatically be using this environment in your project on the future visits to this project, this file can contain "rvm use 1.8.7#your_project_environment" which will achieve this.
install all required gems
If you have additional questions, feel free to visit Wayne E. Seguin and a ton of other users of RVM and we will be happy to help you out. Of course, the first search for answers is the documentation on the web site.