How to find out which gems need to be updated in a Rails app if the Ruby version is upgraded?
For example, I would like to know which of my Rails app gems will have to be upgraded if I upgrade my Ruby from 2.1.3 to 2.2.2. The preference would be to keep the changes minimal as to reduce the probability of things breaking.
The important thing would be for this to be a dry-run. So that one can assess the amount of work that an upgrade will require.
I have checked bundle and gem readme's without much luck.
If you update your rails version, it should install or resolve the required dependencies needed to run the new rails version. As far as as the gems you have entered that are NOT dependencys to Rails, you can check gem compatibility on rubygems.org. Just type in the title of your gem in the search bar.
Related
It causes so many deployment issues it's ridiculous. Most of the time I don't care what version of gems are used, just want to use the latest one.
UPDATE in response to comments:
Here are a couple of examples off the top of my head:
developer A is using a pre-release of a gem so when he runs 'bundle update', the Gemfile.lock is messed up for everyone else and if you deploy it, there goes your site.
A bug in a gem gets fixed so we run gem update across our servers, restart rails and yay, bug fixed! Oh, but wait, it's not fixed? Thanks bundler. What should have been an easy fix is now a full code deploy across our servers.
That's just a couple off the top of my head. At least let us decide if we want to lock in gem versions or perhaps at least allow a range of versions for instance any 2.X version.
UPDATE 2: And yet another issue when there are windows developers on the team
Here is what's showing up in a windows Gemfile.lock:
nokogiri (1.4.4)
nokogiri (1.4.4-x86-mingw32)
Wow, this is just awesome. Sure makes for easy teamwork and deployment.
I recommend starting to use two techniques with your development and deployment:
Specify version number of gems in your gemfile.
For example:
gem "rails", "3.0.1"
gem "will_paginate", "~> 3.0.pre2"
This way, when you decide you want to update rails, or will_paginate, change the version numbers in your gemfile.
Only update certain gems
Rather than the generic bundler update command, run
bundler update rails
This will only update the rails gem to the newest version, rather than get the latest of all gems.
If you use both 1 & 2, you'll have a happier experience.
Then, simply, don't check your Gemfile.lock into source control. All of the specific problems you listed are solved.
Of course, you are sacrificing the enormous advantage that Bundler gives you over any other dependencies management system.
OS X 10.6 has Rails 2.2.2 installed by default.
How to upgrade to Rails 2.3.8?
Since Rails 3 is out, is it possible to have multiple versions of Rails (like 2.3.8 and 3) installed on OS X?
(For example, I could be working on two Rails projects, one is Rails 2.x and the other is Rails 3.x).
Use rvm
RVM is a command line tool which allows us to easily install, manage and work with multiple ruby environments from interpreters to sets of gems...
RVM allows users to deploy each project with its own completely self-contained and dedicated environment--from the specific version of ruby all the way down to the precise set of required gems to run the application. Having a precise set of gems also avoids the issue of version conflicts between projects, causing difficult-to-trace errors and hours of hair loss. With RVM, NO OTHER GEMS than those required are installed. This makes working with multiple complex applications where each has a long list of gem dependencies efficient. RVM allows us to easily test gem upgrades by switching to a new clean set of gems to test with while leaving our original set intact. It is flexible enough to even have a set of gems per environment or development branch--or even individual developer's taste...
I wouldn't bother with gemsets myself just do as other people have mentioned:
gem install -v=2.3.8 rails
and then to use:
rails _2.3.8_ new rails app
Note that this _versionnumber_ thing is a standard way of specifying a version of any rubygems installed executable.
Use
gem install -v=2.3.8 rails
where -v=[version number you want to install]
Then
list gem rails
In your config/environment.rb you can state which version of Rails you want to use.
To upgrade your OS version of the rails gem:
sudo gem install rails --version 2.3.8
While you're at it, you can also upgrade your OS rubygems system itself, overwriting the binary that OS X comes with. This might seem kind of hacky, but it's a stable thing that everyone does.
sudo gem install rubygems-update
sudo update_rubygems
Regarding managing rails versions in your projects, if your only needs are:
Specifying the version of rails that you want on a rails project
Specifying different versions of rails and/or other gems in each of multiple rails projects
Then rvm is overkill. The only thing you need, and what is also a complete and utter pleasure to work with, is Bundler. Bundler is like Software Update for your rails project. In fact, Rails 3 comes with Bundler by default, you just have to list the gems you need in Gemfile and it takes care of the rest. You don't need to worry about which versions of your gems are installed in the OS.
(You do however need the appropriate version of the rails gem installed in the OS in order to generate the rails project in the first place)
http://rubygems.org/
It's all you need =)
Just a bit of background, I come from a strong C#/staticly typed background. Therefore I tend to think in terms of .dlls. So if I was working in a project, I'd reference my required dlls and that would be that.
Being new to Ruby and Rails I find I might be doing something wrong. For example, I create a Rails app at home using the gems I have locally. Using a different computer (say a work computer) I attempt to work on the project only to find I'm using different versions of the gems. After carrying out a bundle install I'm back to a working project.
The issue I have with this is that my gem library becomes 'messy'. I end up with several versions of the same gem. Is this the way others work? When using a gem (from a require) will it default to the latest version? I feel as if I'm not managing the dependencies correctly, though as I've mentioned I'm new to the world of Ruby.
Should I just include my dependencies, then perform a bundle install each time I have different/missing dependencies? What happens if I wish to upgrade to a newer version of a gem? Would it be a case of updating the gemfile that bundle uses and getting on with it?
Yes, bundler is the way to go to work with dependancies with Ruby on Rails. Why ? First, because it's shipped with it (at least for version 3.0). Second, because it's simple as hell (unlike maven with Java).
A non exhaustive list of feature :
it lets you declare one or many gem repository to fetch gems from
to group your dependencies by environment (development, production...)
to specify version you'd like
and so on. For more on this, check this http://gembundler.com/rationale.html
Regarding your question : yes, bundler will take the latest version available is none is specified.
Also, I would add a disavantage : you cannot specify a gem version depending on the OS. For example, nokogiri has a linux version AND a win version.
The default behaviour when requiring a module in a gem is to assume you want the latest version of the gem if you have more than one installed. You can change this by specifying which version you want in a specific application like this:
gem "rails", "2.3.8"
Before you require anything from the gem. This ensures that this application will use the specified version of the gem, even if a newer one is installed.
You can of course clean out obsolete versions of your installed gems whenever you don't need them again, or if you use bundler consistently: just wipe everything and run bundler again to get just your required gems installed.
Another useful tool is the Ruby Version Manager (RVM), in addition to handling different versions of ruby it provides a feature called gemsets which allows you to isolate different applications or environments from eachother. That is App A can have its separate gemset with all its required gems, and App B have another gemset with only its required gems. This will reduce the clutter in your dependencies quite a bit.
I'm working on two different rails installations for two different projects. They are on different versions of rails. Here's what I have installed:
gem list --local | grep rails
shows that I have this installed:
rails (3.0.0.beta4, 2.3.5)
When I run a command to do a deployment for the app that uses 2.3.5, I get the following error:
Missing the Rails 2.3.5 gem. Please `gem install -v=2.3.5 rails`, update your
RAILS_GEM_VERSION setting in config/environment.rb for the Rails version you do
have installed, or comment out RAILS_GEM_VERSION to use the latest version installed.
It's not finding the correct rails version, even though I have it installed. What are good short- and longer-term solutions for this problem?
I suggest you RVM. It allow you to have different ruby/gems versions on the same machine.
The long term solution is to look into rvm, especially the gemset feature makes it really easy to keep separate versions of gems and even ruby versions for different projects.
A short trem solution may be to add the the following line to your boot.rb file, somewhere before rails is required:
gem rails, "2.3.5"
This loads the right version of the gem, otherwise gem will think you want the latest version.
As others have noted, rvm is one way to solve this problem. The other is to use bundler, which involves some setup in your application and potentially requiring you to use 'bundle exec command' everywhere you want to run conflicting versions of a command (eg cucumber)
I have an older Rails app that I need to run. But I have the latest version of Rails.
When I try to run this older app it says:
Missing the Rails 1.99.0 gem. Please
gem install -v=1.99.0 rails
But when I run the command: gem install -v=1.99.0 rails
ERROR: could not find gem rails
locally or in a repository
Not sure what to do next. Could someone help me understand what's happening here?
And my second question, related to this problem is: It seems silly that I need to revert to an older version of Rails just to run this one legacy app - there must be a better way of doing this?
AFAIK, v1.99.0 is sort of a v2.0 prerelease, so you could try installing v2.0.x, changing the RAILS_GEM_VERSION in config/environment.rb and runing rake rails:update.
If you think about it, it's not as silly as it might seem at first. You make an app using a fast evolving web framework as RoR. Your choices are: continue developing your app at aproximately the same pace the framework is evolving, or freeze the rails gem (and evertything else your app depends on, like gems, plugins) into your app in order to make it less fragile to expecting gem updates.
Regarding the second question: yes it is silly. Fortunately the Rails team spotted that silliness and at some point they gave us the ability to "freeze" the versions of Rails libraries required by an application (and also specific gem versions) into the vendor directory.
To freeze your version of Rails:
rake rails:freeze:gems
There's a good blog post from a while back describing this.
Unless you install and deploy RVM, your installation will roll back your system rails installation, which will impact your other projects. If you want to manually administrate your development environment this way, you can uninstall rails first, and then install the desired version of rails for the current project.
But try to install your rails gem instead with this syntax:
sudo gem install rails -v 1.99.0