Add retries to dockerbuild.sh

Author: Nate McMaster

dockerbuild.sh

@@ -104,6 +104,22 @@ fi
 dockerfile="$DIR/build/docker/$image.Dockerfile"
 tagname="aspnetcore-build-$image"
 
+# Use docker pull with retries to pre-pull the image need by the dockerfile
+# docker build regularly fails with TLS handshake issues for unclear reasons.
+base_imagename="$(grep -E -o 'FROM (.*)' $dockerfile | cut -c 6-)"
+pull_retries=3
+while [ $pull_retries -gt 0 ]; do
+    failed=false
+    docker pull $base_imagename || failed=true
+    if [ "$failed" = true ]; then
+        let pull_retries=pull_retries-1
+        echo -e "${YELLOW}Failed to pull $base_imagename Retries left: $pull_retries.${RESET}"
+        sleep 1
+    else
+        pull_retries=0
+    fi
+done
+
 docker build "$(dirname "$dockerfile")" \
     --build-arg "USER=$(whoami)" \
     --build-arg "USER_ID=$(id -u)" \