Merge lp:~negronjl/charms/precise/zookeeper/trunk into lp:charms/zookeeper

[Juan L. Negron]

Added config option to be able to include an external zookeeper into the quorum.
Added weight and group directives in zoo.cfg for better integration and control of leader.

-Juan

[James Page (james-page)]

Hi Juan

Had a quick review and test - couple of issues:

1) Line 49: + default_group=`config-get default_weight`

Incorrect - should pick the default_group config - as a result generated wacky config and charms fail to upgrade.

2) config-changed hook

Fails - missing symlink to zookeeper-common

3) existing peers/quorum.

I tested this by deploying a zookeeper cluster of three nodes (which formed correctly) and then setting the external server - at which point all three existing unit lost track of each other.

configure_zookeeper is purging all server.* entries from the file - but not then re-adding them based on members of the peer relation.

Cheers

James

review: Needs Fixing

[Juan L. Negron (negronjl)]

Hi James:

Thanks for the review ... I have fixed the issues mentioned in the review ... would you mind reviewing this again ( latest revision atm is revno: 9 ).

Thanks,

Juan

=== modified file 'config.yaml'
--- config.yaml	2012-02-14 12:21:25 +0000
+++ config.yaml	2012-11-21 21:47:21 +0000
@@ -21,3 +21,19 @@
       The packages provides in the hadoop-ubuntu team PPA's are based
       directly on upstream ZooKeeper releases but are not fully built from
       source.
+  default_weight:
+    type: int
+    default: 1
+    description: default weight
+  default_group:
+    type: int
+    default: 0
+    description: default group
+  external_server:
+    type: string
+    default: ""
+    description: |
+      Extra servers ( external to juju ) to add
+      to zoo.cnf.  Format should be id:group:weight:host:port:port
+      group can be defined as "default" as opposed to a number to use
+      the default_group defined above

=== modified file 'hooks/zookeeper-common'
--- hooks/zookeeper-common	2012-02-20 14:00:16 +0000
+++ hooks/zookeeper-common	2012-11-21 21:47:21 +0000
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-set -e
+set -eux
 
 # By default we install from the main Ubuntu archive.
 source=`config-get source`
@@ -55,16 +55,21 @@
 
 configure_zookeeper () {
     juju-log "Purging any standalone configuration..."
-    # This is found in the bigtop default configuration
-    sed -i "/^server.0/d" $zk_conf
+    # Purge
+    sed -i "/^server./d" $zk_conf
+    sed -i "/^weight./d" $zk_conf
+    sed -i "/^group./d" $zk_conf
     juju-log "Generating unique ID for this instance..."
     unit_no=`echo $JUJU_UNIT_NAME | cut -d / -f 2`
+    default_weight=`config-get default_weight`
+    default_group=`config-get default_group`
     echo $unit_no > $zk_myid
     juju-log "Adding this unit to the quorum..."
     hostname=`unit-get private-address`
-    # Purge and re-add as required
-    sed -i "/^server.${unit_no}/d" $zk_conf
+    # Add the config
     echo "server.${unit_no}=${hostname}:2888:3888" >> $zk_conf
+    echo "group.${default_group}=${unit_no}" >> $zk_conf
+    echo "weight.${unit_no}=${default_weight}" >> $zk_conf
     # Expose port as required
     open-port $zk_port
 }
@@ -85,23 +90,84 @@
     service $zk_service stop || :
 }
 
+update_group() {
+    member_id=$1
+    [ -z ${member_id} ] && return 0
+    default_group=`config-get default_group`
+    group_arr=( $(grep "group.${default_group}" ${zk_conf} | awk -F'=' '{ print $2 }' | tr ":" "\n") )
+    member_found="no"
+    for member in "${group_arr[@]}"
+    do
+        [ "${member_id}" == "${member}" ] && member_found="yes"
+    done
+    [ "${member_found}" == "no" ] && group_arr=("${group_arr[@]}" "${member_id}")
+    retVal="group.${default_group}=${group_arr[@]}"
+    retVal=`echo ${retVal} | tr " " ":"`
+    sed -i "s/^group.${default_group}.*/${retVal}/" ${zk_conf}
+    sed -i "s/^group.${default_group}=:/group.${default_group}=/" ${zk_conf}
+}
+
+update_external_server() {
+    # Add extra server ( if configured )
+    external_server=`config-get external_server`
+    if [[ "${external_server}" != "" ]]; then
+        external_id=`echo ${external_server} | cut -d : -f 1`
+        external_group=`echo ${external_server} | cut -d : -f 2`
+        if [[ "${external_group}" == "default" ]]; then
+            external_group=`config-get default_group`
+        fi
+        external_weight=`echo ${external_server} | cut -d : -f 3`
+        external_host=`echo ${external_server} | cut -d : -f 4`
+        external_port1=`echo ${external_server} | cut -d : -f 5`
+        external_port2=`echo ${external_server} | cut -d : -f 6`
+        sed -i "/^server.${external_id}/d" $zk_conf
+        sed -i "/^weight.${external_id}/d" $zk_conf
+        echo "server.${external_id}=${external_host}:${external_port1}:${external_port2}" >> $zk_conf
+	update_group ${external_id}	
+        echo "weight.${external_id}=${external_weight}" >> $zk_conf
+        open-port ${external_port1}
+        open-port ${external_port2}
+    fi
+}
+
 update_quorum() {
+    default_group=`config-get default_group`
+    default_weight=`config-get default_weight`
     # Purge out existing quorum config to deal with departure of
     # ZK nodes
     sed -i "/^server./d" $zk_conf
+    sed -i "/^weight./d" $zk_conf
+    sed -i "/^group./d" $zk_conf
     # Add this node back into the list
     juju-log "Adding this unit to the quorum..."
     unit_no=`echo $JUJU_UNIT_NAME | cut -d / -f 2`
     hostname=`unit-get private-address`
-    echo "server.${unit_no}=${hostname}:2888:3888" >> $zk_conf
+    server_arr[0]="server.${unit_no}=${hostname}:2888:3888"
+    weight_arr[0]="weight.${unit_no}=${default_weight}"
+    group_arr[0]=${unit_no}
     # Re-create based on current relations
     for member in `relation-list`
     do  
         juju-log "Adding $member to quorum"
         member_id=`echo ${member} | cut -d / -f 2`
         member_hostname=`relation-get private-address ${member}`
-        echo "server.${member_id}=${member_hostname}:2888:3888" >> $zk_conf
-    done
+	server_arr=("${server_arr[@]}" "server.${member_id}=${member_hostname}:2888:3888")
+	weight_arr=("${weight_arr[@]}" "weight.${member_id}=${default_weight}")
+	group_arr=("${group_arr[@]}" "${member_id}")
+    done
+    # Dump the new config
+    # servers
+    for server_line in "${server_arr[@]}"
+    do
+        echo "${server_line}" >> ${zk_conf}
+    done
+    # weight
+    for member_line in "${weight_arr[@]}"
+    do
+        echo "${member_line}" >> $zk_conf
+    done
+    # group
+    echo "group.${default_group}=${group_arr[@]}" | tr " " ":" >> $zk_conf
 }
 
 setup_zk_interface() {
@@ -116,6 +182,11 @@
         configure_sources
         install_zookeeper
         configure_zookeeper
+        update_external_server
+        restart_zookeeper
+        ;;
+    config-changed)
+        update_external_server
         restart_zookeeper
         ;;
     start)
@@ -128,6 +199,7 @@
         ;;
     quorum-relation-changed|quorum-relation-departed)
         update_quorum
+        update_external_server
         restart_zookeeper
         ;;
     zookeeper-relation-joined)
@@ -135,6 +207,7 @@
         ;;
     upgrade-charm)
         configure_zookeeper
+        update_external_server
         restart_zookeeper
         ;;
     *)