How to automatically update /var/cfengine/masterfiles on a CFEngine policy hub from a Subversion or Git repository.

changes-to-update.cf

# These go in update.cf (in CFEngine community) or update_policy.cf (in CFEngine Enterprise).
# Once these are in place, you need to manually check out /var/cfengine/masterfiles from the appropriate repository.
# From then on, "svn up" will be run on it periodically to keep it up to date with respect to the repository.

# This needs to be added to the classes: section of the update bundle
# Change .svn to .git to use git.
classes:
   "masterfiles_in_svn"
                   expression => fileexists("$(master_location)/.svn"),
                      comment => "Check if $(master_location) is checked out from subversion",
                       handle => "cfe_internal_update_policy_classes_masterfiles_in_svn";

# This needs to be added to the commands: section of the update bundle

# Again, modify the commands accordingly if using git

  am_policy_hub.masterfiles_in_svn::
    "/usr/bin/svn up"
      contain => u_silent_in_dir("$(master_location)"),
       action => u_ifelapsed("1"),
      comment => "Update masterfiles from svn repository",
       handle => "cfe_internal_update_masterfiles_from_svn";

# You need to add u_silent_in_dir and u_ifelapsed at the end of the update.cf file

#########################################################

body contain u_silent_in_dir(s)
{
 chdir => "$(s)";
 no_output => "true";
}

#########################################################

body action u_ifelapsed(x)
{
 ifelapsed => "$(x)";
}