#!/bin/bash
 #

 # lib/rpc_backend

 # Interface for installing RabbitMQ on the system

 
 # Dependencies:

 #
 # - ``functions`` file

 # - ``RABBIT_{HOST|PASSWORD|USERID}`` 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 (stable interface)
 #
 # Note: if implementing an out of tree plugin for an RPC backend, you
 # should install all services through normal plugin methods, then
 # redefine ``iniset_rpc_backend`` in your code. That's the one portion
 # of this file which is a standard interface.

 
 # Save trace setting
 XTRACE=$(set +o | grep xtrace)
 set +o xtrace
 

 # Functions
 # ---------

 # 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

         # in case it's not actually running, /bin/true at the end
         sudo killall epmd || sudo killall -9 epmd || /bin/true

         if is_ubuntu; then
             # And the Erlang runtime too

             apt_get purge -y erlang*

         fi

     fi

 }
 

 # install rpc backend

 function install_rpc_backend {

     if is_service_enabled rabbit; then
         # Install rabbitmq-server

         install_package rabbitmq-server

     fi

 }
 
 # restart the rpc backend

 function restart_rpc_backend {

     if is_service_enabled rabbit; then
         # Start rabbitmq-server
         echo_summary "Starting RabbitMQ"

         # NOTE(bnemec): Retry initial rabbitmq configuration to deal with
         # the fact that sometimes it fails to start properly.

         # Reference: https://bugzilla.redhat.com/show_bug.cgi?id=1144100

         # NOTE(tonyb): Extend the orginal retry logic to only restart rabbitmq
         # every second time around the loop.
         # See: https://bugs.launchpad.net/devstack/+bug/1449056 for details on
         # why this is needed.  This can bee seen on vivid and Debian unstable
         # (May 2015)
         # TODO(tonyb): Remove this when Debian and Ubuntu have a fixed systemd
         # service file.

         local i

         for i in `seq 20`; do

             local rc=0
 

             [[ $i -eq "20" ]] && die $LINENO "Failed to set rabbitmq password"

             if [[ $(( i % 2 )) == "0" ]] ; then
                 restart_service rabbitmq-server
             fi

 
             rabbit_setuser "$RABBIT_USERID" "$RABBIT_PASSWORD" || rc=$?
             if [ $rc -ne 0 ]; then
                 continue
             fi
 

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

             sudo rabbitmqctl change_password \
                 $RABBIT_USERID $RABBIT_PASSWORD || rc=$?
             if [ $rc -ne 0 ]; then
                 continue;
             fi
 
             break

         done

         if is_service_enabled n-cell; then
             # Add partitioned access for the child cell
             if [ -z `sudo rabbitmqctl list_vhosts | grep child_cell` ]; then
                 sudo rabbitmqctl add_vhost child_cell

                 sudo rabbitmqctl set_permissions -p child_cell $RABBIT_USERID ".*" ".*" ".*"

             fi
         fi

     fi
 }
 

 # builds transport url string
 function get_transport_url {

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

         echo "rabbit://$RABBIT_USERID:$RABBIT_PASSWORD@$RABBIT_HOST:5672/"
     fi
 }
 

 # iniset cofiguration

 function iniset_rpc_backend {

     local package=$1
     local file=$2

     local section=${3:-DEFAULT}

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

         iniset $file $section rpc_backend "rabbit"

         iniset $file oslo_messaging_rabbit rabbit_hosts $RABBIT_HOST
         iniset $file oslo_messaging_rabbit rabbit_password $RABBIT_PASSWORD
         iniset $file oslo_messaging_rabbit rabbit_userid $RABBIT_USERID

         if [ -n "$RABBIT_HEARTBEAT_TIMEOUT_THRESHOLD" ]; then
             iniset $file oslo_messaging_rabbit heartbeat_timeout_threshold $RABBIT_HEARTBEAT_TIMEOUT_THRESHOLD
         fi
         if [ -n "$RABBIT_HEARTBEAT_RATE" ]; then
             iniset $file oslo_messaging_rabbit heartbeat_rate $RABBIT_HEARTBEAT_RATE
         fi

     fi
 }
 

 function rabbit_setuser {
     local user="$1" pass="$2" found="" out=""
     out=$(sudo rabbitmqctl list_users) ||
         { echo "failed to list users" 1>&2; return 1; }
     found=$(echo "$out" | awk '$1 == user { print $1 }' "user=$user")
     if [ "$found" = "$user" ]; then
         sudo rabbitmqctl change_password "$user" "$pass" ||
             { echo "failed changing pass for '$user'" 1>&2; return 1; }
     else
         sudo rabbitmqctl add_user "$user" "$pass" ||
             { echo "failed changing pass for $user"; return 1; }
     fi
     sudo rabbitmqctl set_permissions "$user" ".*" ".*" ".*"
 }
 

 # Restore xtrace
 $XTRACE

 # Tell emacs to use shell-script-mode
 ## Local variables:
 ## mode: shell-script
 ## End: