[Solr] Use new Solr base

data/Dockerfiles/solr/Dockerfile

@@ -1,11 +1,23 @@
-FROM solr:7.7-alpine
+FROM solr:7.7-slim
+
 USER root
+
+ENV GOSU_VERSION 1.11
+
 COPY docker-entrypoint.sh /
 COPY solr-config-7.7.0.xml /
 COPY solr-schema-7.7.0.xml /
 
-
-RUN apk --no-cache add su-exec curl tzdata \
+RUN dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')" \
+  && wget -O /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/download/$GOSU_VERSION/gosu-$dpkgArch" \
+  && chmod +x /usr/local/bin/gosu \
+  && gosu nobody true \
+  && apt-get update && apt-get install -y --no-install-recommends \
+  tzdata \
+  curl \
+  bash \
+  && apt-get autoclean \
+  && rm -rf /var/lib/apt/lists/* \
   && chmod +x /docker-entrypoint.sh \
   && sync \
   && bash /docker-entrypoint.sh --bootstrap

data/Dockerfiles/solr/docker-entrypoint.sh

@@ -37,10 +37,10 @@ if [[ "${1}" == "--bootstrap" ]]; then
   rm /opt/solr/server/solr/configsets/_default/conf/managed-schema
 
   echo "Starting local Solr instance to setup configuration"
-  su-exec solr start-local-solr
+  gosu solr start-local-solr
 
   echo "Creating core \"dovecot-fts\""
-  su-exec solr /opt/solr/bin/solr create -c "dovecot-fts"
+  gosu solr /opt/solr/bin/solr create -c "dovecot-fts"
 
   # See https://github.com/docker-solr/docker-solr/issues/27
   echo "Checking core"
@@ -52,10 +52,10 @@ if [[ "${1}" == "--bootstrap" ]]; then
   echo "Created core \"dovecot-fts\""
 
   echo "Stopping local Solr"
-  su-exec solr stop-local-solr
+  gosu solr stop-local-solr
 
   exit 0
 fi
 
-exec su-exec solr solr-foreground
+exec gosu solr solr-foreground