If you get this error when you try to resize an OpenStack instance:

# nova resize example 23 --poll
ERROR: Resize requires a change in size. (HTTP 400)

You need to change your flavor to have a different memory size. It's a bug in an older OpenStack version:

        # /nova/compute/api.py
        if (current_memory_mb == new_memory_mb) and flavor_id:		
            raise exception.CannotResizeToSameSize()

which got fixed 2012-09-12 ([https://git.openstack.org/cgit/openstack/nova/commit/nova/compute/api.p...

All the hidden and not hidden features of Git and GitHub.

Directory of popular Github projects.

Development environment setup

Rails Composer

Basically a comprehensive Rails Template. Prepares your development environment and lets you select web server, template engine, unit and integration testing frameworks and more.

Generate an app in minutes using an application template. With all the options you want!

Code generators

Rails Bricks

A command line wizard. Once you get it running, it creates sleek applications.

RailsBricks enables you to cre...

Using git checkout - you can switch back to the branch you previously worked on.

(master) $ git checkout foobar
Switched to branch 'foobar'
(foobar) $ git checkout -
Switched to branch 'master'
(master) $

This also works with other commands like git merge:

(master) $ git checkout foobar
Switched to branch 'foobar'
(foobar) $ git merge -
Merged branch 'master'

If you recorded a bad fix for a conflict, you can tell git to forget that bad resolution:

git rerere forget your_file.rb

Afterwards, the badly resolved file will still be in your working directory. To get it back with confict markers, say:

git checkout -m your_file.rb

Resolve the conflict again, properly now. ;)

Introducing Trailer from HouseTrip, a simple menu bar app that helps you manage your GitHub pull requests. It’s one feature we felt was lacking from our workflow!

There seems to be no way to use therubyracer -v '0.11.4' and libv8 -v '3.11.8.17' on OS X Mavericks.

However, running bundle update therubyracer worked for me. It installed therubyracer -v '0.12.1' and libv8 -v '3.16.14.3' and I had not side effects.

Log of my attempts to get it working

Probably you got here when bundling failed building native extensions for therubyracer.

The libv8 (3.3.10.4) should have been installed when bundling. Unfortunately it is not building correctly on Mavericks, so the libv8.a f...

We have released Modularity 2. It has many incompatible changes. See below for a script to migrate your applications automatically.

There is no does method anymore

We now use traits with the vanilla include method:

class Article < ActiveRecord::Base
  include DoesTrashable
end

When your trait has parameters, use square brackets:

class Article < ActiveRecord::Base
  include DoesStripFields[:name, :brand]
end

Note how you ...

I am using git at several places: at work, at university, and at home. I want an own git user/email for each of those places, but I don't want to care setting the values each time I create or clone a new repository.

Git allows for setting user/email per repository, globally and system-wide, but I need a fourth dimension: per directory. By setting git environment variables using ondir, I managed to get exactly what I need.

1. Install ondir (on a Mac: brew install ondir, other OSs need to install it from the linked page).
2. Put these ...

It's mixins (modules) for Coffeescript classes. Other than most homegrown approaches, this one allows you to keep using super.

Establishing a new SSH connection usually takes only a few seconds, but if you’re connecting to a server multiple times in succession the overhead starts to add up. If you do a lot of Git pushing and pulling or frequently need to SSH to a dev server, you’ve probably felt the pain of waiting for SSH to connect so you can get back to doing work.

For all late night coders:

The program "redshift" changes your monitors' white balance according to your position on the planet and your local time. This is supposed to put less strain on your eyeballs than staring at a "daylight white" screen all day and night.
The program is in the Ubuntu repositories, so a simple "sudo apt-get install gtk-redshift" transfers it onto your hard drive.

I find the effect rather pleasing and so I have set the following alias on my computer:

alias rdshft='gtk-redshift -l 48.3714407:10.8982552 -t 6500:4200 &'...

I had some problems with Git and the file spec/fixtures/ČeskýÁČĎÉĚÍŇÓŘŠŤÚŮÝŽáčďéěíňóřšťúůýž. After pulling the latest commits, it would show that file as untracked, but adding and committing it would throw error: pathspec 'check in unicode fixture file once again' did not match any file(s) known to git.

Solution

Install Git version > 1.8.2 using homebrew and set

git config --global core.precomposeunicode true

Done.

Reason

According to the linked Stackoverflow post ...

... the cause is the different im...

When you have files in your .gitignore they won't be considered for changes, but still you might want to get rid of them, e.g. because they clutter your file system.

While a regular git clean will ignore them as well, passing the -x switch changes that:

git clean -x

If you want to see what would happen first, make sure to pass the -n switch for a dry run:

git clean -xn

Clean even harder by passing the -f (force cleaning under certain circumstances; I think this is also required by default) or -d (removes director...

So you're hunting down a regression (or just a bug) and want to use git bisect to find out when it was introduced? Smart kid.
If you have a shell command ready to reveal if your current state is good or bad, you can have git do most of the work for you.

Using git bisect run <your command> you can tell git that your command will reveal the issue; git on the other hand will use the return value of that call to decide if the state is good or bad.
...

Using CSS sprites for background images is a technique for optimizing page load time by combining smaller images into a larger image sprite.

There are ongoing arguments on how useful this still is, as modern browsers become more comfortable to load images in parallel. However, many major websites still use them, for example amazon, [facebook](...

This card shows how to upgrade a Rails 2 application from Rails 2.3.8 through every single patch level up to 2.3.18, and then, hopefully, Rails LTS.

2.3.8 to 2.3.9

This release has many minor changes and fixes to prepare your application for Rails 3.

Step-by-step upgrade instructions:

0. Upgrade rails gem
1. Change your environment.rb so it says RAILS_GEM_VERSION = '2.3.9'
2. Change your ...

Backbone plugin to override getters and setters with logic.

In order to have more human readable git branches, do

  git pull --rebase

To always pull like this, write these lines to your ~/.gitconfig:

[pull]
   rebase = true

..or use this oneliner

git config --global pull.rebase true

Note that this will break if you pull from other upstream branches like

git pull origin other-branch

If you keep rebasing by default, you can get "merge pulls" like this:

git pull --no-rebase origin other-branch

Essential backports that enable many of the nice features of Ruby 1.8.7 up to 2.0.0 for earlier versions.

In order to clone a git repository including all branches and tags you need to use two parameters when cloning the old and pushing to the new repository respectively:

git clone --bare http://example.com/old-repo.git
cd old-repo
git push --mirror http://example.com/new-repo.git

Of course, the URLs to your repository might look different depending on the protocol used, username required, etc.
For a user git using the git protocol, it could be git@example.com:repository-namespace/repository.git

Sometimes you want git to ignore certain files that appear on your machine. You can do this in 3 ways:

• Per project, in the project's .gitignore file
• Per project, in a local exclude file
• Globally on your machine

Downsides of per-project .gitignore entries

While it might be tempting to set it per project (other devs might benefit from it), you

• need to do it each time for every project
• "pollute" a project's .gitignore file with stuff...