D

D is a (very) simple Drush wrapper, with very specific features,

Reduce the amount of arguments and typing
Enable running the same Drush command on multiple targets
Support switching between multiple Drush versions

Reduce arguments and typing

Drush commands often consist of multiple arguments and parameters, eg:

drush @somehost -y --verbose updb

Drush site aliases are fantastic, but working for longer periods on the same project, constantly specifying the same site aliases and arguments becomes tedious.

D allows you to set the site alias using an environment variable that will be used instead of having to specify it as a parameter when calling Drush.

The same applies to arguments, so the above example can be significantly reduced by setting the variables accordingly,

export DHOST="somehost"
export DFLAG="-y --verbose"

Thus drush @somehost -y --verbose updb is reduced to,

d updb

If you briefly need to run Drush on another host, you can always call Drush directly, like you'd normally do,

drush @someotherhost pm-list

D does not interfere with the default Drush settings.

Running Drush on multiple targets

By setting DHOST to multiple site aliases, the given command and arguments are run on each of the site aliases,

export DHOST="host1 host2"

Thus d cc all runs the following commands in sequence,

drush @host1 cc all
drush @host2 cc all

Multiple concurrent Drush versions

Often, multiple versions of Drush are installed at your local development environment. Instead of having to explicitly call the desired version with an absolute path to the drush script, this can be done by setting the DROOT variable to the directory containing the desired Drush version.

export DROOT="/usr/local/drush6"
export DHOST="somehost"

Thus d dd runs /usr/local/drush6/drush @somehost dd.
Of course, DFLAG is also used, if set.

Installation

Put this somewhere in your PATH variable, and make sure it's executable.
Some shells define an alias for d, so you might need to add unalias d to your shell configuration file (~/.bash_profile or ~/.zshrc) for D to work.

D blindly assumes that whatever you put in DHOST is a valid Drush site alias, and makes no attempt of validating this exists. If you do not set DROOT, Drush is assumed to be available in PATH.

Troubleshooting

Call D directly with an absolute path, eg. /home/you/bin/d if you suspect that your shell alias for d might kick in.

If you encounter strange behavior when running the script, add -x to the first line to enable debugging mode. Thus the first line goes from,

#/bin/bash

to,

#/bin/bash -x

Adding --debug and --verbose to DFLAG also enables very verbose debug messages to be printed when Drush runs.

Recommendations

Set DHOST and DFLAG in your shell configuration file (~/.bash_profile or ~/.zshrc) to reduce the amount of times you have to set these.

Better yet, use a session configurator like tmuxinator and create a session for each project, in which these variables are set.
That allows for rapidly switching between projects and ensuring that the environment is properly configured.

Disclaimer

Use this at your own risk.
Take care and type less.

rkk/d