Merge lp:~launchpad-baby-gnu/ubumirror/feature-abort-on-remote-update-in-progress into lp:ubumirror

[Daniel Dehennin]

My patch add some checks on remote mirror state.

It minimize the risk of synchronising a dists/ directory not related to pool/ if our synchronisation speed is slower than the remote one :

- we start synchronising pool/
- remote start its own synchronisation and finish
- synchronisation of pool/ finish for us
- we start synchronising dists/

In which case our current dists/ does not have the proper pool/.

Unmerged revisions

85. By Daniel Dehennin <email address hidden> on 2015-12-04

Check remote state before synchronising dist

Sometimes, the synchronisation of pool/ is long enough for remote mirror
to begin a new synchronisation before we start synchronising dists/.

We need to check if remote “project/trace/” has changed since we started
as the remote mirror could be faster than us.

* ubuarchive: Call “check_remote_state” before syncing pool and dist.
 (check_remote_state): Check remote “Archive-Update-in-Progress” lock
 and if remote “project/trace/” has changed.
 (_clean_on_exit): function to clean everything at EXIT.

84. By Daniel Dehennin <email address hidden> on 2015-02-27

Abort if the remote update is in progress

* ubuarchive: Test if remote 'Archive-Update-in-Progress-*' is present.

=== modified file 'ubuarchive'
--- ubuarchive	2014-06-08 05:58:41 +0000
+++ ubuarchive	2015-12-04 13:49:51 +0000
@@ -39,9 +39,40 @@
     exit 2
 fi
 
+check_remote_state() {
+    if rsync ${UBUARC_MIRROR}/Archive-Update-in-Progress-* > /dev/null 2>&1; then
+	echo "$(date -R): Remote mirror update is in progress: abort."
+	exit 1
+    fi
+
+    if [ ! -d "${STATE_DIR}/init" ]; then
+	rsync -a --delete --delete-after ${UBUARC_MIRROR}/project/trace ${STATE_DIR}/init
+    elif rsync -a --delete --delete-after ${UBUARC_MIRROR}/project/trace ${STATE_DIR}/check; then
+	if ! diff -qr ${STATE_DIR}/init/ ${STATE_DIR}/check/; then
+	    echo "$(date -R): Remote mirror was updated during our synchronisation: abort."
+	    exit 1
+	fi
+    else
+	echo "$(date -R): Unable to check remote state: abort."
+	exit 1
+    fi
+}
+
+_clean_on_exit() {
+    EXIT_CODE=$?
+
+    # Do not abort on failure as we are in SIGHANDLER
+    set +e
+    rm -f "${LOCK}" > /dev/null 2>&1
+    [ ! -d "${STATE_DIR}" ] || rm -rf "${STATE_DIR}"
+
+    savelog -c 28 -n $LOGFILE > /dev/null
+}
+
 LOCK="${UBUARC_DIR}/Archive-Update-in-Progress-${HOSTNAME}"
+STATE_DIR=$(mktemp -d -t ubuarchive-XXXXXXXX)
 
-trap 'rm -f $LOCK > /dev/null 2>&1; savelog -c 28 -n $LOGFILE > /dev/null' EXIT
+trap _clean_on_exit EXIT
 
 # Get in the right directory and set the umask
 cd $HOME
@@ -62,6 +93,8 @@
 
 echo "$(date -R): Lock established for process $(cat $LOCK)."
 
+check_remote_state
+
 set +e
 echo "$(date -R): Initiating Ubuntu archive pool sync..."
 
@@ -82,6 +115,8 @@
 
 echo "$(date -R): Ubuntu archive pool sync completed."
 
+check_remote_state
+
 echo "$(date -R): Initiating Ubuntu archive dists and indices sync..."
 
 rsync -av --partial --delete --delete-after \