create wrapper script in order to wait for Nextcloud to start

Signed-off-by: Simon L <szaimen@e.mail.de>

Dockerfile

@@ -3,5 +3,17 @@ WORKDIR /app
 
 COPY ./build/libs/* ./nextcloud-dlna.jar
 
+RUN set -ex; \
+    export DEBIAN_FRONTEND=noninteractive; \
+    apt-get update; \
+    apt-get install -y --no-install-recommends \
+        tzdata \
+        netcat-openbsd \
+    ; \
+    rm -rf /var/lib/apt/lists/*;
+
+COPY --chmod=775 start.sh /start.sh
+
 EXPOSE 8080
+ENTRYPOINT /start.sh
 CMD ["java","-jar","nextcloud-dlna.jar"]

start.sh

@@ -0,0 +1,12 @@
+#!/bin/bash
+
+# Wait for Nextcloud to come online
+if [ -n "$NC_DOMAIN" ] && [ "$NC_PORT" ]; then
+    while ! nc -z "$NC_DOMAIN" "$NC_PORT"; do
+        echo "Waiting for Nextcloud to start..."
+        sleep 5
+    done
+fi
+
+# Execute CMD
+exec /__cacert_entrypoint.sh "$@"