gistfile1.txt

From cc44b6cf52d4fdb4341f18e29ee0244a222b8e3a Mon Sep 17 00:00:00 2001
From: Will Palmer <wmpalmer@gmail.com>
Date: Fri, 11 Feb 2011 08:30:23 +0000
Subject: [PATCH] add GL_POST_UPDATE_PRE_APPLY hook capability

One can use a "secondary" post-update hook to run additional tasks when
the gitolite-admin repository is updated. However, up until now there
was nowhere to prevent other, perhaps-dependent updates from running in
the event that those secondary tasks are known to be impossible or
undesired. This had the potential to leave the updates in a
"half-released" state, which is something some people want to avoid, as
one of the benefits of putting things in gitolite-admin is to keep a
history of gitolite states.

Here we narrow the gap by providing a place for a "post-update,
pre-apply" hooks, which can run additional checks on these secondary
tasks, and exit unsuccessfully if they determine that the secondary
tasks would not, or should not, complete. The main post-update hook can
then pick up on this, and refuse to run much in the same way it refuses
to run if its own checks fail.
---
 conf/example.gitolite.rc         |    1 +
 doc/2-admin.mkd                  |   10 ++++++++++
 doc/gitolite.rc.mkd              |   11 +++++++++++
 hooks/gitolite-admin/post-update |   14 ++++++++++++++
 4 files changed, 36 insertions(+), 0 deletions(-)

diff --git a/conf/example.gitolite.rc b/conf/example.gitolite.rc
index d800357..dd5343b 100644
--- a/conf/example.gitolite.rc
+++ b/conf/example.gitolite.rc
@@ -52,6 +52,7 @@ $HTPASSWD_FILE = "";
 $RSYNC_BASE = "";
 $SVNSERVE = "";
 # $UPDATE_CHAINS_TO = "hooks/update.secondary";
+# $ADMIN_POST_UPDATE_PRE_APPLY = "hooks/gl-post-update-pre-apply";
 # $ADMIN_POST_UPDATE_CHAINS_TO = "hooks/post-update.secondary";
 # $GL_ADC_PATH = "";
 # $GL_GET_MEMBERSHIPS_PGM = "/usr/local/bin/expand-ldap-user-to-groups"
diff --git a/doc/2-admin.mkd b/doc/2-admin.mkd
index ebc1a4d..0b3eb88 100644
--- a/doc/2-admin.mkd
+++ b/doc/2-admin.mkd
@@ -106,6 +106,16 @@ Sometimes it is necessary to do something whenever a new repo is created.  If
 you need this functionality, just supply a hook called "gl-post-init" with
 whatever code you want in it.
 
+<a name="_gl_post_update_pre_apply"></a>
+
+#### "gl-post-update-pre-apply" hook
+
+It can be desirable to add additional checks on the state of the admin
+repository prior to allowing it to apply its updates. To allow this, gitolite
+will run an extra "gl-post-update-pre-apply" hook, if it exists, and use its
+exit status to determine whether or not to proceed with the update and further
+chained hooks.
+
 <a name="_hook_chaining"></a>
 
 #### hook chaining
diff --git a/doc/gitolite.rc.mkd b/doc/gitolite.rc.mkd
index a0f2710..4f6cf03 100644
--- a/doc/gitolite.rc.mkd
+++ b/doc/gitolite.rc.mkd
@@ -216,6 +216,17 @@ on feedback from my users to find or fix issues.
 
         $SVNSERVE = "/usr/bin/svnserve -r /var/svn/ -t --tunnel-user=%u";
 
+  * hook checking
+
+      * `$ADMIN_POST_UPDATE_PRE_APPLY`, string, default
+        "hooks/gl-post-update-pre-apply"
+
+    By default, the post-update hook in the admin repo checks the exit status
+    of the "gl-post-update-pre-apply" hook prior to running the guts of the
+    post-update. If you're okay with the default, there's no need to change
+    this, but you can use this variable to set a different name or path for the
+    hook if you want to.
+
   * hook chaining
 
       * `$UPDATE_CHAINS_TO`, string, default "hooks/update.secondary"
diff --git a/hooks/gitolite-admin/post-update b/hooks/gitolite-admin/post-update
index b7cbbb0..54a8415 100755
--- a/hooks/gitolite-admin/post-update
+++ b/hooks/gitolite-admin/post-update
@@ -13,6 +13,20 @@ GIT_WORK_TREE=$GL_ADMINDIR git ls-tree --name-only master |
         exit 1
     }
 
+ADMIN_POST_UPDATE_PRE_APPLY=`$GL_BINDIR/gl-query-rc ADMIN_POST_UPDATE_PRE_APPLY`
+[ -n "$ADMIN_POST_UPDATE_PRE_APPLY" ] || ADMIN_POST_UPDATE_PRE_APPLY=hooks/gl-post-update-pre-apply
+if [ -f $ADMIN_POST_UPDATE_PRE_APPLY ] || [ -L $ADMIN_POST_UPDATE_PRE_APPLY ]
+then
+    $ADMIN_POST_UPDATE_PRE_APPLY "$@"
+    if [ $? -ne 0 ]
+    then
+        echo "*** ERROR ***" >&2
+        echo "exiting due to nonzero exit status of POST_UPDATE_PRE_APPLY script" >&2
+        echo "until that script exits successfully, the post-update hook will not run" >&2
+        exit 1
+    fi
+fi
+
 # checkout the master branch to $GL_ADMINDIR
 # (the GL_ADMINDIR env var would have been set by gl-auth-command)
 GIT_WORK_TREE=$GL_ADMINDIR git checkout -f --quiet master
-- 
1.7.4.1.287.g1ecf2