Always pull image on arm

Author: xfalcox

launcher

@@ -198,14 +198,16 @@ check_prereqs() {
     echo "WARNING: Docker version ${test} deprecated, recommend upgrade to ${docker_rec_version} or newer."
   fi
 
-  case `uname -m` in
+  arm=false
+  case $(uname -m) in
     armv7l)
       echo "ERROR: 32bit arm is not supported. Check if your hardware support arm64, which is supported in experimental capacity."
       exit 1
       ;;
     aarch64 | arm64)
       echo "WARNING: Support for aarch64 is experimental at the moment. Please report any problems at https://meta.discourse.org/tag/arm "
       image="discourse/base:aarch64"
+      arm=true
       read -n 1 -s -r -p "Press any key to continue"
       ;;
     x86_64)
@@ -221,7 +223,8 @@ check_prereqs() {
   # 4. discourse docker image is downloaded
   test=`$docker_path images | awk '{print $1 ":" $2 }' | grep "$image"`
 
-  if [ -z "$test" ]; then
+  # arm experimental support is on a fixed tag, always pull
+  if [ -z "$test" ] || [ $arm = true ]; then
     echo
     echo "WARNING: We are about to start downloading the Discourse base image"
     echo "This process may take anywhere between a few minutes to an hour, depending on your network speed"