Configuring powerline to show working Git branch

So the documentation for Powerline kind of sucks. I followed this pretty good article on getting started with it. First thing I noticed however is that the if statement on the article doesn’t work if you don’t have powerline installed (which kind of defeats the purpose of having the if statement there at all).

# if powerline is installed, then use it
command -v powerline-daemon &>/dev/null
if [ $? -eq 0 ]; then
powerline-daemon -q
POWERLINE_BASH_CONTINUATION=1
POWERLINE_BASH_SELECT=1
. /usr/share/powerline/bash/powerline.sh
fi

Next up is the configuration. I primarily use my bash prompt as a way to indicate which branch I’m working in within a Git repository. You need to point at the default_leftonly theme which is pretty easy to find when you web search for it. The issue is everything seems to just point you at the powerline docs, which aren’t the most clear.

First, start by creating a local configuration directory that will override the configuration for powerline for your user.

$ mkdir -p ~/.config/powerline

Then the next thing is to copy over the config.json from the main powerline configuration directory where you can find the available color schemes and other shell, i3, vim, etc themes.

(Again, the documentation kind of sucks on where the root of these configurations live…)

On my Fedora 22 system they live in /etc/xdg/powerline/. I then copy the config.json from that directory to ~/.config/powerline

To get the Git branch stuff going, I modified the configuration file in the following way:

--- /etc/xdg/powerline/config.json 2015-02-18 18:56:51.000000000 -0500
+++ /home/lmadsen/.config/powerline/config.json 2015-09-09 17:11:43.937522571 -0400
@@ -18,7 +18,7 @@
},
"shell": {
"colorscheme": "default",
- "theme": "default",
+ "theme": "default_leftonly",
"local_themes": {
"continuation": "continuation",
"select": "select"

To make it active you can run powerline-config --reload. If you have any errors in your configuration (I actually ran into this when playing with the colorscheme setting and used “solorized” instead of “solarized”), you can check it with powerline-lint.

Selecting Chef Servers With Environment Variables

Today I got playing around with dynamically selecting different chef servers in preparation for migrating some of our nodes away from our chef-dev server to our chef-live server (which I’m currently in the process of building and populating with data). I had been talking in the #chef IRC channel a few weeks back about making things dynamic, or at least easily switchable, when using multiple chef servers for different groups of servers in an environment.

What I want to do, is be able to set an environment variable at my console in order to switch between chef servers. Previously I had been doing this with different files in my ~/.chef/ directory and changing symlinks between the files. This method works, but is kind of annoying. So with the help of some of the folks in #chef, and with this gist of a sample file that someone is using for their hosted chef environment, I was able to build my own knife.rb and commit it to our chef.git repository.

In our chef.git repository, I created a directory .chef and placed a knife.rb file in it:

$ cd ~/src/chef-repo
$ mkdir .chef
$ touch .chef/knife.rb

I then filled knife.rb with the following contents:

current_dir = File.dirname(__FILE__)

sys_user = ENV["USER"]

log_level                :info
log_location             STDOUT
node_name                sys_user
client_key               "#{ENV["HOME"]}/.chef/#{ENV["KNIFE_ENV"]}/#{ENV["USER"]}.pem"
validation_client_name   "chef-validator"
validation_key           "#{ENV["HOME"]}/.chef/#{ENV["KNIFE_ENV"]}/validator.pem"
chef_server_url          "http://chef-#{ENV["KNIFE_ENV"]}.shifteight.org:4000"
cache_type               'BasicFile'
cache_options( :path => "#{ENV['HOME']}/.chef/checksums" )
cookbook_path            [ "#{current_dir}/../cookbooks", "#{current_dir}/../site-cookbooks" ]

The main key is the KNIFE_ENV environment variable which I set using: export KNIFE_ENV=dev or export KNIFE_ENV=live

After setting the environment variable, which server I’m using is selected for me. Additionally, I copied my validation.pem and client.pem files into corresponding directories in my ~/.chef/ directory: $ mkdir ~/.chef/{live,dev}

With all that done, I can now easily switch between our different servers in order to start the migration of our nodes. (I might create another blog post about that in the future if I get a chance.)

“BUT HOW DO I KNOW WHICH ENVIRONMENT I’M WORKING WITH?!?!?!”, you say? Oh fancy this little PS1 and function I added to my ~/.bashrc file:

if [ "$KNIFE_ENV" == "" ]; then
 export KNIFE_ENV="dev"
fi

function which_env {
  if [ "$KNIFE_ENV" == "live" ]; then
    echo "31"
  else
    echo "32"
  fi
}

export PS1='[\u@\h \[\033[0;36m\]\W$(__git_ps1 "\[\033[0m\]\[\033[0;33m\](%s) \[\033[0;`which_env`m\]~$KNIFE_ENV~")\[\033[0m\]]\$ '

Is nice 🙂

bash creating files named ‘1’ everywhere!

So I ran into something kind of stupid today 🙂 Adding a little note for anyone who might run into a similar instance.

I have some ssh-add stuff that gets run in my .bashrc file, but when I was outputting it, I was doing:

ssh-add ~/.ssh/some_key > /dev/null 2&>1

Note the 2&>1 at the end. That means to redirect output to a file named 1. You need to flip the &> into >&, so the fixed version looks like:

ssh-add ~/.ssh/some_key > /dev/null 2>&1

rpmlint non-utf8-spec-file error

I’ve been doing a bunch of work with RPMs lately, and while running rpmlint against a spec file I was modifying, I received this error:

myfile.spec: E: non-utf8-spec-file myfile.spec

After Googling, I ran into a way of finding the non-compliant characters.

$ iconv -f ISO-8859-8 -t UTF-8 myfile.spec > converted.spec
$ diff -u myfile.spec converted.spec

(Answer thanks to Dominique Leuenberger @ http://lists.opensuse.org/opensuse-packaging/2011-04/msg00005.html)

.bashrc trick for git repo and branch information

The other day I was talking to my friend Russell Bryant who pointed me to some .bashrc magic that would show me which branch I was currently working with inside a git repo on my system. I found it incredibly handy and have modified the ANSI colour coding slightly.

export PS1='[\u@\h \[33[0;36m\]\W$(__git_ps1 "\[33[0m\]\[33[0;33m\](%s)")\[33[0m\]]\$ '

On Fedora Russell mentioned that you need the bash-completion installed. We’re unsure if you need anything on other distributions.

Edit: January 6, 2012
As I’m using my laptop today, I modified the .bashrc file on Ubuntu 10.04, and here is the PS1 code I came up with. It’s nearly the same, but I’m using bold today instead of the unbolded colours of lore.

PS1='${debian_chroot:+($debian_chroot)}\[\033[28;01m\]\u@\h\[\033[00m\]:\[\033[1;36m\]\W$(__git_ps1 "\[\033[00m\]\[\033[1;33m\](%s)")\[\033[00m\]\$ '