I have a Gem that I found at RubyForge and want to peek inside to see what code it contains. Is it possible to do this without installing the Gem on my system?
Also, if I use RVM on Mac OS X, does that at all change how my gems get installed (assuming I have one gemset)?
gem unpack unpacks the gem without installing it.
Gems on RubyGems usually have a link to the source code (most often on GitHub), in which case you can easily browse the code (I use this A LOT).
The "homepage" link also tends to link to the repository.
If all else fails, go to GitHub and search for the name of the gem (you may need to match up the authors to ensure it's the right repository for the gem).
Edit:
Just noticed that you asked about gems on Rubyforge. In which case my first step would be to check RubyGems. But otherwise you will need to download the gem and peek inside it (it's just a compressed archive so you can open it up in something like 7-zip).
Many gems have their source freely readable. The way that always works is to install it.
If you just want to browse the source; go to the gem on http://rubygems.org find your gem and use the "Source code" link.
In case of RubyForge you can find the links under the SCM link in the menu.
I'm sort of new to bundler and the files it generates. I have a copy of a git repo from GitHub that is being contributed to by many people so I was surprised to find that bundler created a file that didn't exist in the repo and wasn't in the .gitignore list.
Since I have forked it, I know adding it to the repo won't break anything for the main repo, but if I do a pull request, will it cause a problem?
Should Gemfile.lock be included in the repository?
Update for 2022 from TrinitronX
Fast-forward to 2021 and now Bundler docs [web archive] now say to commit the Gemfile.lock inside a gem... ¯_(ツ)_/¯ I guess it makes sense for developers and ease of use when starting on a project. However, now CI jobs need to be sure to remove any stray Gemfile.lock files to test against other versions.
Legacy answer ~2010
Assuming you're not writing a rubygem, Gemfile.lock should be in your repository. It's used as a snapshot of all your required gems and their dependencies. This way bundler doesn't have to recalculate all the gem dependencies each time you deploy, etc.
From cowboycoded's comment below:
If you are working on a gem, then DO NOT check in your Gemfile.lock. If you are working on a Rails app, then DO check in your Gemfile.lock.
Here's a nice article explaining what the lock file is.
The real problem happens when you are working on an open-source Rails app that needs to have a configurable database adapter. I'm developing the Rails 3 branch of Fat Free CRM.
My preference is postgres, but we want the default database to be mysql2.
In this case, Gemfile.lock still needs be checked in with the default set of gems, but I need to ignore changes that I have made to it on my machine. To accomplish this, I run:
git update-index --assume-unchanged Gemfile.lock
and to reverse:
git update-index --no-assume-unchanged Gemfile.lock
It is also useful to include something like the following code in your Gemfile. This loads the appropriate database adapter gem, based on your database.yml.
# Loads the database adapter gem based on config/database.yml (Default: mysql2)
# -----------------------------------------------------------------------------
db_gems = {"mysql2" => ["mysql2", ">= 0.2.6"],
"postgresql" => ["pg", ">= 0.9.0"],
"sqlite3" => ["sqlite3"]}
adapter = if File.exists?(db_config = File.join(File.dirname(__FILE__),"config","database.yml"))
db = YAML.load_file(db_config)
# Fetch the first configured adapter from config/database.yml
(db["production"] || db["development"] || db["test"])["adapter"]
else
"mysql2"
end
gem *db_gems[adapter]
# -----------------------------------------------------------------------------
I can't say if this is an established best practice or not, but it works well for me.
My workmates and I have different Gemfile.lock, because we use different platforms, windows and mac, and our server is linux.
We decide to remove Gemfile.lock in repo and create Gemfile.lock.server in git repo, just like database.yml. Then before deploy it on server, we copy Gemfile.lock.server to Gemfile.lock on server using cap deploy hook
Agreeing with r-dub, keep it in source control, but to me, the real benefit is this:
collaboration in identical environments (disregarding the windohs and linux/mac stuff). Before Gemfile.lock, the next dude to install the project might see all kinds of confusing errors, blaming himself, but he was just that lucky guy getting the next version of super gem, breaking existing dependencies.
Worse, this happened on the servers, getting untested version unless being disciplined and install exact version. Gemfile.lock makes this explicit, and it will explicitly tell you that your versions are different.
Note: remember to group stuff, as :development and :test
Simple answer in the year 2021:
Gemfile.lock should be in the version control also for Rubygems. The accepted answer is now 11 years old.
Some reasoning here (cherry-picked from comments):
#josevalim https://github.com/heartcombo/devise/pull/3147#issuecomment-52193788
The Gemfile.lock should stay in the repository because contributors and developers should be able to fork the project and run it using versions that are guaranteed to work.
#rafaelfranca https://github.com/rails/rails/pull/18951#issuecomment-74888396
I don't think it is a good idea to ignore the lock file even for plugins.
This mean that a "git clone; bundle; rake test" sequence is not guarantee to be passing because one of yours dozens of dependencies were upgraded and made your code break. Also, as #chancancode said, it make a lot harder to bisect.
Also Rails has Gemfile.lock in git:
https://github.com/rails/rails/commit/0ad6d27643057f2eccfe8351409a75a6d1bbb9d0
The Bundler docs address this question as well:
ORIGINAL: http://gembundler.com/v1.3/rationale.html
EDIT: http://web.archive.org/web/20160309170442/http://bundler.io/v1.3/rationale.html
See the section called "Checking Your Code into Version Control":
After developing your application for a while, check in the
application together with the Gemfile and Gemfile.lock snapshot. Now,
your repository has a record of the exact versions of all of the gems
that you used the last time you know for sure that the application
worked. Keep in mind that while your Gemfile lists only three gems
(with varying degrees of version strictness), your application depends
on dozens of gems, once you take into consideration all of the
implicit requirements of the gems you depend on.
This is important: the Gemfile.lock makes your application a single
package of both your own code and the third-party code it ran the last
time you know for sure that everything worked. Specifying exact
versions of the third-party code you depend on in your Gemfile would
not provide the same guarantee, because gems usually declare a range
of versions for their dependencies.
The next time you run bundle install on the same machine, bundler will
see that it already has all of the dependencies you need, and skip the
installation process.
Do not check in the .bundle directory, or any of the files inside it.
Those files are specific to each particular machine, and are used to
persist installation options between runs of the bundle install
command.
If you have run bundle pack, the gems (although not the git gems)
required by your bundle will be downloaded into vendor/cache. Bundler
can run without connecting to the internet (or the RubyGems server) if
all the gems you need are present in that folder and checked in to
your source control. This is an optional step, and not recommended,
due to the increase in size of your source control repository.
No Gemfile.lock means:
new contributors cannot run tests because weird things fail, so they won't contribute or get failing PRs ... bad first experience.
you cannot go back to a x year old project and fix a bug without having to update/rewrite the project if you lost your local Gemfile.lock
-> Always check in Gemfile.lock, make travis delete it if you want to be extra thorough https://grosser.it/2015/08/14/check-in-your-gemfile-lock/
A little late to the party, but answers still took me time and foreign reads to understand this problem. So I want to summarize what I have find out about the Gemfile.lock.
When you are building a Rails App, you are using certain versions of gems in your local machine. If you want to avoid errors in the production mode and other branches, you have to use that one Gemfile.lock file everywhere and tell bundler to bundle for rebuilding gems every time it changes.
If Gemfile.lock has changed on your production machine and Git doesn't let you git pull, you should write git reset --hard to avoid that file change and write git pull again.
The other answers here are correct: Yes, your Ruby app (not your Ruby gem) should include Gemfile.lock in the repo. To expand on why it should do this, read on:
I was under the mistaken notion that each env (development, test, staging, prod...) each did a bundle install to build their own Gemfile.lock. My assumption was based on the fact that Gemfile.lock does not contain any grouping data, such as :test, :prod, etc. This assumption was wrong, as I found out in a painful local problem.
Upon closer investigation, I was confused why my Jenkins build showed fetching a particular gem (ffaker, FWIW) successfully, but when the app loaded and required ffaker, it said file not found. WTF?
A little more investigation and experimenting showed what the two files do:
First it uses Gemfile.lock to go fetch all the gems, even those that won't be used in this particular env. Then it uses Gemfile to choose which of those fetched gems to actually use in this env.
So, even though it fetched the gem in the first step based on Gemfile.lock, it did NOT include in my :test environment, based on the groups in Gemfile.
The fix (in my case) was to move gem 'ffaker' from the :development group to the main group, so all env's could use it. (Or, add it only to :development, :test, as appropriate)
There is a common pattern:
there are many developers working on one project and the Gemfile(.lock) is shared via SCM. But what if some developers want to use different tools for testing and development? How to do it?
The problem is, that when you put conditional sections to your Gemfile, also the Gemfile.lock will be different for each developer and therefor you'll get conflict each time you commit to SCM.
Is there some simple, widely acknowledged solution?
I like to have this in my Gemfile:
local_gemfile = File.dirname(__FILE__) + "/Gemfile.local"
if File.file?(local_gemfile)
require local_gemfile
end
I also have Gemfile.local and Gemfile.lock in gitignore. I know I'm not "supposed to", but I don't think the caveats (such as the ones you mention in your question) are worth it.
UPDATE for Bundler 1.0.10 as of March 3, 2011
local_gemfile = File.dirname(__FILE__) + "/Gemfile.local.rb"
if File.file?(local_gemfile)
self.instance_eval(Bundler.read_file(local_gemfile))
end
I had to use this with Rails 3 and Bundler 1.0.10.
If you check in something that depends on a gem that gem should be in the gemfile. If the code in the repository does not depend on a gem, there's no need to have it in the gemfile. So, unless your developers don't check in their tests (which would be weird) you would need all the test's dependencies if you want to run the whole tests suite anyway.
If the gems aren't necessary to run the app or its tests the gems don't need to be in the gemfile. Just have each developer create a gemset (I assume you're using RVM, if you don't you should) for the app and install whatever they need there, and then just add what the app needs to run to the gemfile.
You can use Bundler's without flag to exclude groups.
If you have the following Gemfile
group :jakubs_testing_tools do
gem "rspec"
gem "faker"
end
You can exclude them with bundle install
$ bundle install --without jakubs_testing_tools
http://gembundler.com/groups.html
It won't help you right now, but there's been an open feature request for Bundler to add support for a Gemfile.local for ages. It is planned for somewhere in the 1.x series, so stay tuned.
If your main problem is developer-specific IRB gems, there are a couple of workarounds in the issue's comments.
I suppose the install_if method (added recently) solves the problem:
install_if -> { `whoami`.strip == 'jakub' } do
gem "pry-rails"
end
See http://bundler.io/v1.14/man/gemfile.5.html#INSTALL_IF
Each developer can create their own branch - Bundler works fine with different branches having different Gemfile contents. It's a good idea for developers to prefix branch names with their initials, to avoid confusion or collisions.
(basically the same idea as in August Lilleaas's comment: gitignore)
Put the default/minimal Gemfile in SCM and then have developers change it on their systems and never commit. Have them add it to their inactive changeset in their SVN client (if they use one), other SCMs should have something similar.
This is how we do this in my company - works really well :)
With Jeweler I created a gem folder structure with ease.
However, I still have some questions:
Why are params like --gemcutter and --rubyforge still available for Jeweler. Aren't these replaced by RubyGems? Do I have to specify anything to create a gem for RubyGems?
In the Rakefile I have information about the gem, and when I run "rake install" it created a gemspec. Why is the same information in two places?
What is a manifest? Just read about it, haven't seen such file.
How do I make my gem callable from the shell once I have installed it, like rails. Cause right now it's just accessible through a Ruby script using require.
Should I use "jeweler release" or "gem push" to push my gem to RubyGems.org?
I have to specify "handle" when signing up in RubyGems. What is that?
Thanks.
jeweler was created before RubyGems became what it is, so it still reflects the split. I'm not sure when jeweler was last updated, either. (I think it also still recognizes building gems on Github, which is now disabled.)
I'm not sure I follow what you're saying. The specification in the Rakefile details what the spec that gets written should look like. The spec that gets written details what should be installed and how, I believe.
A manifest is a list of all the files that your gem should ship with. Not everyone uses one. See the hoe documentation for some pro-manifest discussion.
Many Ruby gems are only libraries. If you want yours to also have a program like jeweler or rake or rails that you can call, you have to write the callable program, put it in bin in your gem's layout and specify (in your gemspec) that it should be packaged and installed. See the Gem::Specification reference under files and executable.
Not sure. Consult both jeweler's docs and the docs for RubyGems.
You can give an email address or use a name (a 'handle', like I use Telemachus here), which is all they mean by 'handle'.
For the record, if you are just learning how to write gems, you do not need to upload your first attempts using RubyGems or anything like it. You can simply install the gem on your machine only.
I am trying to hack through a forked gem (buildr). As such I cloned it from github and began to butcher the code. The official gem is installed on my system (under /usr/lib/ruby.../gems/buildr...). There is an executable which I need to use in my dev process - buildr.
Now I want the buildr executable and the library to point to my forked repo and not the default gem installation. This would be for this gem only. As such, the changes I make against the forked repo is usable directly for testing and so forth.
I would guess I need to load my library prior to the system gem loading. Can somebody recommend the best way to do so?
I did something similar for work when the Spreadsheet gem broke backward compatibility. I put the previous versions code in it's own module and just renamed the gem my-spreadsheet and installed that (I really wanted some of the features of the new gem but I also didn't want to rewrite all my previous code at that point).
If it's just a binary you want to override you could always do some PATH magic, setting the directory of your binary first and thus make sure you always override. But personally I'd prefer making my own copy with a new name and installing that.
you could bump the version in the gemspec for your fork. Then when you install your version of the gem, it will use your (newer) version by default.
change buildr.gemspec
#...
spec.version = '1.3.4.dev'
#...
Then
$ gem build buildr.gemspec
$ sudo gem install buildr-1.3.4.dev.gem
and it should work.