Here is a sequence of commands and output that show how I keep the Acquia Drupal open source content management system up to date with Mercurial, the open source distributed version control system.
In the example below, my Mercurial repositories for Drupal are located in the “drupal” subdirectory of my “repo” folder. Once I’ve moved into that directory, I download the Acquia Drupal distribution with curl and then extract it into my previously-created Mercurial working directory, “acquia_drupal,” using tar.
$ curl -O http://acquia.com/files/downloads/acquia-drupal-1.2.0.3780.tar.gz
$ tar —strip-path=1 —directory=acquia_drupal —recursive-unlink -zxvf acquia-drupal-1.2.0.3780.tar.gz
(Update: I added the —recursive-unlink option after I noticed that the Acquia Network control panel keeps track of extra — possibly unneeded — files and folders you have in your install. The recursive unlink option seems to avoid having stray files from old versions of modules hanging around in your repository after you install updates.)
After extracting Acquia Drupal my Mercurial working directory, I get the status of the repository. It shows there are changes from the last version I checked in — and this includes new files, denoted by a “?” at the beginning of their line.
$ hg status
M profiles/acquia/acquia.profile
? modules/acquia/acquia_connector/README.txt
? modules/acquia/acquia_connector/acquia_agent/acquia.ico
? modules/acquia/acquia_connector/acquia_agent/acquia_agent.info
? modules/acquia/acquia_connector/acquia_agent/acquia_agent.install
? modules/acquia/acquia_connector/acquia_agent/acquia_agent.module
? modules/acquia/acquia_connector/acquia_agent/acquia_agent.pages.inc
? modules/acquia/acquia_connector/acquia_agent/acquia_agent_drupal_version.inc
? modules/acquia/acquia_connector/acquia_agent/acquia_agent_streams.inc
? modules/acquia/acquia_connector/acquia_spi/acquia_spi.info
? modules/acquia/acquia_connector/acquia_spi/acquia_spi.install
? modules/acquia/acquia_connector/acquia_spi/acquia_spi.module
Since there are new files, I have to add them so they’ll be tracked by the repository. I only need to add in the parent directory for any changed files, and any new files within it will also be added for tracking.
adding modules/acquia/acquia_connector/README.txt
adding modules/acquia/acquia_connector/acquia_agent/acquia.ico
adding modules/acquia/acquia_connector/acquia_agent/acquia_agent.info
adding modules/acquia/acquia_connector/acquia_agent/acquia_agent.install
adding modules/acquia/acquia_connector/acquia_agent/acquia_agent.module
adding modules/acquia/acquia_connector/acquia_agent/acquia_agent.pages.inc
adding modules/acquia/acquia_connector/acquia_agent/acquia_agent_drupal_version.inc
adding modules/acquia/acquia_connector/acquia_agent/acquia_agent_streams.inc
adding modules/acquia/acquia_connector/acquia_spi/acquia_spi.info
adding modules/acquia/acquia_connector/acquia_spi/acquia_spi.install
adding modules/acquia/acquia_connector/acquia_spi/acquia_spi.module
$ hg status
M profiles/acquia/acquia.profile
A modules/acquia/acquia_connector/README.txt
A modules/acquia/acquia_connector/acquia_agent/acquia.ico
A modules/acquia/acquia_connector/acquia_agent/acquia_agent.info
A modules/acquia/acquia_connector/acquia_agent/acquia_agent.install
A modules/acquia/acquia_connector/acquia_agent/acquia_agent.module
A modules/acquia/acquia_connector/acquia_agent/acquia_agent.pages.inc
A modules/acquia/acquia_connector/acquia_agent/acquia_agent_drupal_version.inc
A modules/acquia/acquia_connector/acquia_agent/acquia_agent_streams.inc
A modules/acquia/acquia_connector/acquia_spi/acquia_spi.info
A modules/acquia/acquia_connector/acquia_spi/acquia_spi.install
A modules/acquia/acquia_connector/acquia_spi/acquia_spi.module
Excellent; the new files have been added. After this, I just need to accommodate the deleted files that no longer need to be tracked (created when using the “—recursive-unlink” option on tar). For that, see my newer instructions.
Now that the right files are being tracked, I need to commit the changes — modified, added, and deleted files — to the repository. This will create a new revision in the repository’s history, which I’ll tag with the text “Acquia Drupal 1.2.0.”
$ hg tag "Acquia Drupal 1.2.0"
$ hg tip
changeset: 10:423c84439928
tag: tip
user: Jeremy Reichman <jaharmi@jaharmi.com>
date: Wed Jan 14 21:07:23 2009 -0600
summary: Added tag Acquia Drupal 1.2.0 for changeset 0df92d3d243d
Once this revision is checked in, I can use it to propagate changes to other repositories. I keep the main Acquia Drupal distribution in its own repository, and then use the “hg fetch” command to pull its changes into one where I track contributed modules. That second repository is then pulled into a third repository which stores just the changes for my production Web site. The use of three repositories in this way modularizes and isolates the updates.