I'm pretty new to Ruby and have been reading up about Gemfiles and the like. Recently we were bitten by this bug in one of our programs:
https://github.com/ffi/ffi/issues/440
However, in looking through the Gemfile in question, the ffi gem wasn't listed. It is now, pinned to a prior (working) version for the OS in question.
But I'm wondering how things worked before if it wasn't in the Gemfile to start? Are there some 'core' gems out there that come along for the ride, with no need to put them in a Gemfile?
Gems have dependencies and so they get installed as well. You can check your Gemfile.lock to see exactly which gems are installed.
Related
I have a gem that I one of the owner/authors (hyperloop) that depends on another gem (opal-rails) which depends on another gem (opal-jquery).
All gems depend on the gem opal. The problem is the current released version of opal-query is locked to an older version of the opal gem.
The version of opal-jquery on master is okay. For whatever reason the author(s) have not pushed ruby gems, so I have to work around this.
The work around is that I have to say
gem 'hyperloop'
gem "opal-jquery", git: "https://github.com/opal/opal-jquery.git", branch: "master"
in the application Gemfile.
I am hoping somebody can give a workaround that could be embedded in the hyperloop gemspec, so that the problem is taken care of there.
I thought if I added
gem "opal-jquery", git: "https://github.com/opal/opal-jquery.git", branch: "master"
to the hyperloop Gemfile this would take care of it, but apparently not.
There isn't really a way to manage the dependencies of your dependencies. You have 2 options here:
1) Use an older version of opal
2) Clone the opal-jquery gem and modify its Gemfile, pointing to the version of opal you want it to use, then, in your Gemfile, point the opal-jquery gem to pull from your cloned version of the repo
Neither of these is really ideal and you'd have issues if you ever decided to upgrade to a newer version of opal-jquery if you go with the second route
I´m finishing a Ruby Gem that depends on Chromium (jxBrowser). Chromium is quite large and has versions for linux, mac and windows. Releasing this gem to RubyGem is not possible, as the gem size is larger than supported by RubyGem. So, are there any recommendations on where/how to release this? I´d love to keep it in RubyGem as my other gens were released there. Should I release an installer in RubyGem and put the files in GitHub? What´s the best way?
Thanks for any hints and suggestions....
You can ask your users to install the gem from git (bundler: http://bundler.io/git.html, Install Gem from Github Branch?).
This will result in a line like
gem 'hard_drive_expander', github: 'rodrigo/hard_drive_expander'
in a Gemfile (or a bit a lengthier process for gem install - do you intend 'library' kind of usage or standalone installations). Note that depending on your scenario you could have an installer gem that depends on the "github-hosted" gem, or downloads and builds/installs it (both seem like dirty solutions to me though, its not what I expect or commonly see).
Although github does place quotas on your repositories, you will probably not hit them (https://help.github.com/articles/what-is-my-disk-quota/).
Another option is to host it yourself (http://guides.rubygems.org/run-your-own-gem-server/).
Sorry for the "linky" answer.
However, #icguida and #engineersmnky s comments to your question are very worth considering: Do you really need to include chromium?
Update
There is a gem that will hook into gem to allow for usage like this: gem specific_install https://github.com/githubsvnclone/rdoc.git. The gem is called specific_install: https://github.com/rdp/specific_install .
I am not sure what the differences are between these two tools. There seems to be a big overlap, but I have been using RVM and facing some miss-compatibility issues.
What does Bundler do that RVM does not?
They serve different purposes. RVM creates a sandbox to manage your Ruby installations. As a part of that, it also lets you define gemsets.
Bundler doesn't manage your Rubies, it works with the currently selected Ruby.
So, I think you should consider RVM as the configuration manager for your development environment, and Bundler the gem manager for an application.
EDIT: Additional thoughts -
Whether we use RVM or not, typically we'd have to load all the gems we're going to use for an app by hand, using gem install blah, for every gem we want to use.
I end up managing my gems across multiple Rubies by hand. Once they're installed I can create gemsets using RVM, but RVM won't automatically retrieve a particular version of a gem if it's not installed, or go get it again if it was removed. Because RVM is more concerned with your Ruby environment, it mostly leaves the versioning of gems to gem and to us.
Bundler, on the other hand, does care about those missing parts in RVM. When you create the Gemfile for bundler, it will retrieve the necessary gems and specific versions if specified. So, the task of installing a Ruby app on a different machine becomes much simpler. Push the files to the other machine, then run bundle install and it'll do the rest.
It works nicely with Rails and is a sensible solution for my production files. It will be much simpler than how I have to handle Perl distributions in order to run Perl apps on the same hosts.
RVM is more like a containment unit. While Bundler is like a manifest (dependency manager) of what the application will require or use in it's lifecycle (among other things).
If you are working in Rails, you will not be able to escape Bundler. But I use it all the time just so I know what Gems I'll need, and so will others who later come into the project.
RVM helps me separate out my Rubies and then further into Rubies/projects. This way I don't have a slew of Gems and different versions all in one pile.
Not exactly the most action packed answer, but hope it helps a little.
To directly answer your question...
What does Bundler do that RVM does
not?
Bunlder will install all gems that are needed by a project (that uses bundler, and have all needed gems specified in a Gemfile). RVM does not do this.
Using the Gemfile you can specify what gem groups (ie: development, testing)...
There are many 'small' things like these that bundler does but RVM does not. In general as the good people above explained, RVM has a different set of goals from that of bundler. RVMs about managing ruby runtimes while bundler is about managing dependent gems for a application.
Bundler is a tool for managing dependencies in your code -- i.e., all the gems it requires. It will make sure that all the gems you specify in your Gemfile, and any dependencies, are installed on your system. It doesn't really care which version of ruby you are using, it just installs the gems for you under whichever interpreter is in use.
RVM is a tool for running multiple rubies, and in theory, multiple gemsets as well. It doesn't handle dependencies for you at all -- it's still up to you to install the gems.
My experience (and I'm new to RVM), is that you don't want to bother with RVM unless you have a need for running multiple rubies, or need gems installed for different projects that somehow conflict with each other. Even if you are using RVM, it makes sense to use Bundler to manage gem dependencies so that your Gemfile can be tracked in whatever code repository you are using.
I'm writing a new gem I'm basing off of Yehuda's new gem template and I'm slightly confused. Having a Gemfile with dependencies, and also specifying a gemspec with dependencies seems redundant to me. Can someone explain why this is desirable and if it's truly necessary?
Note, this is the first gem I've ever written so I'm new to all of this.
The .gemspec dependencies tell rubygems what it needs to grab to resolve the dependencies when a user installs your gem. The Gemfile is to manage the dependencies while you develop the gem. Rubygems and Bundler aren't connected, at least not yet.
The gemspec is required to build the gem. The Gemfile is more of a convenience, so that people who are working on your gem can easily pull in all the dependencies via Bundler. In the case that you're developing multiple related gems at once, you may also want to put git sources in the Gemfile, so all of the HEAD versions can be tested against.
I am trying to install the mechanize gem that is supposed to work with 1.9 from here: http://github.com/kemiller/mechanize but I do not know how to add it manually.
I am using Windows, I could just copy the folder to the gems directory, but how do I initialize it?
I'm not sure I understand the problem. gem install mechanize doesn't work? It produces version 0.9.3 for me, which matches the gemspec of the library you linked to.
EDIT: you're on 1.9. I knew that. Disregard my hasty post, not familiar enough with Windows to offer any help on building the extensions.
I would use the bundler gem using the command gem install bundler. This will create a file called Gemfile in your project directory where you can put your dependencies for the specific project that you are working on. In the Gemfile, you will need to specify gem mechanize. If you want a specific version include ~> VERSION after. After, run the command bundle install. This will install the gem you want and use it in your project.