[improve] Removed unnecessary native libraries from Docker images (apache#22230)

Author: merlimat

docker/pulsar/Dockerfile

@@ -18,14 +18,19 @@
 #
 
 # First create a stage with just the Pulsar tarball and scripts
-FROM busybox as pulsar
+FROM alpine as pulsar
+
+RUN apk add zip
 
 ARG PULSAR_TARBALL
 
 ADD ${PULSAR_TARBALL} /
 RUN mv /apache-pulsar-* /pulsar
 RUN rm -rf /pulsar/bin/*.cmd
 
+COPY build-scripts /build-scripts/
+RUN /build-scripts/remove-unnecessary-native-binaries.sh
+
 COPY scripts/* /pulsar/bin/
 
 # The final image needs to give the root group sufficient permission for Pulsar components

docker/pulsar/build-scripts/remove-unnecessary-native-binaries.sh

@@ -0,0 +1,51 @@
+#!/usr/bin/env sh
+#
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+set -e
+
+# Retain only native libraries for the architecture of this
+# image
+ARCH=$(uname -m)
+
+# Remove extra binaries for Netty TCNative
+if [ "$ARCH" = "aarch64" ]
+then
+  TC_NATIVE_TO_KEEP=linux-aarch_64
+else
+  TC_NATIVE_TO_KEEP=linux-$ARCH
+fi
+ls /pulsar/lib/io.netty-netty-tcnative-boringssl-static*Final-*.jar | grep -v $TC_NATIVE_TO_KEEP | xargs rm
+
+# Prune extra libs from RocksDB JAR
+mkdir /tmp/rocksdb
+cd /tmp/rocksdb
+ROCKSDB_JAR=$(ls /pulsar/lib/org.rocksdb-rocksdbjni-*.jar)
+unzip $ROCKSDB_JAR > /dev/null
+
+if [ "$ARCH" = "x86_64" ]
+then
+  ROCKSDB_TO_KEEP=linux64-musl
+else
+  ROCKSDB_TO_KEEP=linux-$ARCH-musl
+fi
+
+ls librocksdbjni-* | grep -v librocksdbjni-${ROCKSDB_TO_KEEP}.so | xargs rm
+rm $ROCKSDB_JAR
+zip -r -9 $ROCKSDB_JAR * > /dev/null