# lib/rpc_backend

# Interface for interactig with different rpc backend

# rpc backend settings

# Dependencies:

# ``functions`` file

# ``RABBIT_{HOST|PASSWORD}`` must be defined when RabbitMQ is used

# ``stack.sh`` calls the entry points in this order:

#

# check_rpc_backend

# install_rpc_backend

# restart_rpc_backend

# iniset_rpc_backend

# Save trace setting

XTRACE=$(set +o | grep xtrace)

set +o xtrace

# Functions

# ---------

# Make sure we only have one rpc backend enabled.

# Also check the specified rpc backend is available on your platform.

function check_rpc_backend() {

local rpc_needed=1

# We rely on the fact that filenames in lib/* match the service names

# that can be passed as arguments to is_service_enabled.

# We check for a call to iniset_rpc_backend in these files, meaning

# the service needs a backend.

rpc_candidates=$(grep -rl iniset_rpc_backend . | awk -F/ '{print $NF}')

for c in ${rpc_candidates}; do

if is_service_enabled $c; then

rpc_needed=0

break

fi

done

local rpc_backend_cnt=0

for svc in qpid zeromq rabbit; do

is_service_enabled $svc &&

((rpc_backend_cnt++))

done

if [ "$rpc_backend_cnt" -gt 1 ]; then

echo "ERROR: only one rpc backend may be enabled,"

echo " set only one of 'rabbit', 'qpid', 'zeromq'"

echo " via ENABLED_SERVICES."

elif [ "$rpc_backend_cnt" == 0 ] && [ "$rpc_needed" == 0 ]; then

echo "ERROR: at least one rpc backend must be enabled,"

echo " set one of 'rabbit', 'qpid', 'zeromq'"

echo " via ENABLED_SERVICES."

fi

if is_service_enabled qpid && ! qpid_is_supported; then

die $LINENO "Qpid support is not available for this version of your distribution."

fi

}

# clean up after rpc backend - eradicate all traces so changing backends

# produces a clean switch

function cleanup_rpc_backend {

if is_service_enabled rabbit; then

# Obliterate rabbitmq-server

uninstall_package rabbitmq-server

sudo killall epmd

if is_ubuntu; then

# And the Erlang runtime too

sudo aptitude purge -y ~nerlang

fi

elif is_service_enabled qpid; then

if is_fedora; then

if [[ $DISTRO =~ (rhel6) ]]; then

uninstall_package qpid-cpp-server

else

uninstall_package qpid-cpp-server-daemon

fi

elif is_ubuntu; then

uninstall_package qpidd

else

exit_distro_not_supported "qpid installation"

fi

elif is_service_enabled zeromq; then

if is_fedora; then

uninstall_package zeromq python-zmq

elif is_ubuntu; then

uninstall_package libzmq1 python-zmq

elif is_suse; then

uninstall_package libzmq1 python-pyzmq

else

exit_distro_not_supported "zeromq installation"

fi

fi

}

# install rpc backend

function install_rpc_backend() {

if is_service_enabled rabbit; then

# Install rabbitmq-server

# the temp file is necessary due to LP: #878600

tfile=$(mktemp)

install_package rabbitmq-server > "$tfile" 2>&1

cat "$tfile"

rm -f "$tfile"

elif is_service_enabled qpid; then

if is_fedora; then

if [[ $DISTRO =~ (rhel6) ]]; then

install_package qpid-cpp-server

# RHEL6 leaves "auth=yes" in /etc/qpidd.conf, it needs to

# be no or you get GSS authentication errors as it

# attempts to default to this.

sudo sed -i.bak 's/^auth=yes$/auth=no/' /etc/qpidd.conf

else

install_package qpid-cpp-server-daemon

fi

elif is_ubuntu; then

install_package qpidd

sudo sed -i '/PLAIN/!s/mech_list: /mech_list: PLAIN /' /etc/sasl2/qpidd.conf

sudo chmod o+r /etc/qpid/qpidd.sasldb

else

exit_distro_not_supported "qpid installation"

fi

elif is_service_enabled zeromq; then

if is_fedora; then

install_package zeromq python-zmq

elif is_ubuntu; then

install_package libzmq1 python-zmq

elif is_suse; then

install_package libzmq1 python-pyzmq

else

exit_distro_not_supported "zeromq installation"

fi

fi

}

# restart the rpc backend

function restart_rpc_backend() {

if is_service_enabled rabbit; then

# Start rabbitmq-server

echo_summary "Starting RabbitMQ"

if is_fedora || is_suse; then

# service is not started by default

restart_service rabbitmq-server

fi

# change the rabbit password since the default is "guest"

sudo rabbitmqctl change_password guest $RABBIT_PASSWORD

elif is_service_enabled qpid; then

echo_summary "Starting qpid"

restart_service qpidd

fi

}

# iniset cofiguration

function iniset_rpc_backend() {

local package=$1

local file=$2

local section=$3

if is_service_enabled zeromq; then

iniset $file $section rpc_backend ${package}.openstack.common.rpc.impl_zmq

elif is_service_enabled qpid; then

iniset $file $section rpc_backend ${package}.openstack.common.rpc.impl_qpid

if is_ubuntu; then

QPID_PASSWORD=`sudo strings /etc/qpid/qpidd.sasldb | grep -B1 admin | head -1`

iniset $file $section qpid_password $QPID_PASSWORD

iniset $file $section qpid_username admin

fi

elif is_service_enabled rabbit || { [ -n "$RABBIT_HOST" ] && [ -n "$RABBIT_PASSWORD" ]; }; then

iniset $file $section rpc_backend ${package}.openstack.common.rpc.impl_kombu

iniset $file $section rabbit_host $RABBIT_HOST

iniset $file $section rabbit_password $RABBIT_PASSWORD

fi

}

# Check if qpid can be used on the current distro.

# qpid_is_supported

function qpid_is_supported() {

if [[ -z "$DISTRO" ]]; then

GetDistro

fi

# Qpid was introduced to Ubuntu in precise, disallow it on oneiric; it is

# not in openSUSE either right now.

( ! ([[ "$DISTRO" = "oneiric" ]] || is_suse) )

}

# Restore xtrace

$XTRACE

# Local variables:

# mode: shell-script

# End: