update dockerfile to use zookeeper 3.5.6

This patch updates the Dockerfile to pull zookeeper 3.5.6
from the right repo.

Also, since version 3.5.* version, most
of the 4 letter word commands must be whitelist before they
can actually be used. This patch whitelist all of the during
zookeeper boot

Author: vmakoto

docker/Dockerfile

@@ -5,18 +5,21 @@ ZK_DATA_LOG_DIR=/var/lib/zookeeper/log \
 ZK_LOG_DIR=/var/log/zookeeper \
 JAVA_HOME=/usr/lib/jvm/java-8-openjdk-amd64
 
+ARG ZK_VERSION=3.5.6
+ARG ZK_DIST=zookeeper-$ZK_VERSION
+
 COPY zookeeper-authors-keys .
 
-ARG ZK_DIST=zookeeper-3.4.10
 RUN set -x \
     && apt-get update \
     && apt-get install -y openjdk-8-jre-headless wget netcat-openbsd \
-	&& wget -q "http://www.apache.org/dist/zookeeper/$ZK_DIST/$ZK_DIST.tar.gz" \
-    && wget -q "http://www.apache.org/dist/zookeeper/$ZK_DIST/$ZK_DIST.tar.gz.asc" \
+	&& wget -O "$ZK_DIST.tar.gz" -q "http://www.apache.org/dist/zookeeper/$ZK_DIST/apache-$ZK_DIST-bin.tar.gz" \
+    && wget -O "$ZK_DIST.tar.gz.asc" -q "http://www.apache.org/dist/zookeeper/$ZK_DIST/apache-$ZK_DIST-bin.tar.gz.asc" \
     && export GNUPGHOME="$(mktemp -d)" \
     && gpg --import zookeeper-authors-keys \
-    && gpg --batch --verify "apache-$ZK_DIST.tar.gz.asc" "apache-$ZK_DIST.tar.gz" \
-    && tar -xzf "$ZK_DIST.tar.gz" -C /opt \
+    && gpg --batch --verify "$ZK_DIST.tar.gz.asc" "$ZK_DIST.tar.gz" \
+    && mkdir opt/$ZK_DIST \
+    && tar -xzf "$ZK_DIST.tar.gz" -C /opt/$ZK_DIST --strip-components 1 \
     && rm -r "$GNUPGHOME" "$ZK_DIST.tar.gz" "$ZK_DIST.tar.gz.asc" \
     && ln -s /opt/$ZK_DIST /opt/zookeeper \
     && rm -rf /opt/zookeeper/CHANGES.txt \
@@ -43,7 +46,7 @@ RUN set -x \
 COPY scripts /opt/zookeeper/bin/
 
 # Create a user for the zookeeper process and configure file system ownership 
-# for nessecary directories and symlink the distribution as a user executable
+# for necessary directories and symlink the distribution as a user executable
 RUN set -x \
 	&& useradd $ZK_USER \
     && [ `id -u $ZK_USER` -eq 1000 ] \
@@ -52,5 +55,4 @@ RUN set -x \
 	&& chown -R "$ZK_USER:$ZK_USER" /opt/$ZK_DIST $ZK_DATA_DIR $ZK_LOG_DIR $ZK_DATA_LOG_DIR /tmp/zookeeper \
 	&& ln -s /opt/zookeeper/conf/ /usr/etc/zookeeper \
 	&& ln -s /opt/zookeeper/bin/* /usr/bin \
-	&& ln -s /opt/zookeeper/$ZK_DIST.jar /usr/share/zookeeper/ \
 	&& ln -s /opt/zookeeper/lib/* /usr/share/zookeeper 

docker/README.md

@@ -1,6 +1,6 @@
 # Docker Image
 The docker image contained in this repository is comprised of a base Ubuntu 16.04 image using the latest release of the 
-OpenJDK JRE based on the 1.8 JVM and the latest stable release of ZooKeeper, 3.4.10. Ubuntu is a much larger image than 
+OpenJDK JRE based on the 1.8 JVM and the latest stable release of ZooKeeper, 3.5.6. Ubuntu is a much larger image than 
 BusyBox or Alpine, but these images contain mucl or ulibc. This requires a custom version of OpenJDK to be built 
 against a libc runtime other than glibc. No vendor of the ZooKeeper software supplies or verifies the software against 
 such a JVM, and, while Alpine or BusyBox would provide smaller images, we have prioritized a well known environment.

docker/scripts/start-zookeeper

@@ -185,6 +185,7 @@ function print_servers() {
 }
 
 function create_config() {
+    cat $CONFIG_FILE
     rm -f $CONFIG_FILE
     echo "#This file was autogenerated DO NOT EDIT" >> $CONFIG_FILE
     echo "clientPort=$CLIENT_PORT" >> $CONFIG_FILE
@@ -197,8 +198,9 @@ function create_config() {
     echo "minSessionTimeout=$MIN_SESSION_TIMEOUT" >> $CONFIG_FILE
     echo "maxSessionTimeout=$MAX_SESSION_TIMEOUT" >> $CONFIG_FILE
     echo "autopurge.snapRetainCount=$SNAP_RETAIN_COUNT" >> $CONFIG_FILE
-    echo "autopurge.purgeInteval=$PURGE_INTERVAL" >> $CONFIG_FILE
-     if [ $SERVERS -gt 1 ]; then
+    echo "autopurge.purgeInterval=$PURGE_INTERVAL" >> $CONFIG_FILE
+    echo "4lw.commands.whitelist=*" >> $CONFIG_FILE
+    if [ $SERVERS -gt 1 ]; then
         print_servers >> $CONFIG_FILE
     fi
     cat $CONFIG_FILE >&2