add syslog-ng to base image

Dockerfile

@@ -1,10 +1,12 @@
 FROM alpine:3.5
 MAINTAINER Sebastian Hugentobler <sebastian@vanwa.ch>
 
-ENV S6_OVERLAY_VERSION=v1.18.1.5
+ENV S6_OVERLAY_VERSION=v1.19.1.1
 
-RUN apk --no-cache add libressl
+RUN apk --no-cache add libressl syslog-ng
 RUN wget -qO- https://github.com/just-containers/s6-overlay/releases/download/$S6_OVERLAY_VERSION/s6-overlay-amd64.tar.gz | tar -xz -C /
 RUN apk del libressl
 
+ADD /rootfs /
+
 ENTRYPOINT ["/init"]

rootfs/etc/services.d/syslog-ng/run

@@ -0,0 +1,4 @@
+#!/usr/bin/with-contenv sh
+
+cd /var
+exec syslog-ng --foreground

rootfs/etc/syslog-ng/syslog-ng.conf

@@ -0,0 +1,24 @@
+@version: 3.7
+
+options {
+    stats_freq (0);
+    time_reopen (10);
+    chain_hostnames (off);
+    use_dns (no);
+    use_fqdn (no);
+    keep_hostname (yes);
+};
+
+source s_local {
+    unix-dgram("/dev/log");
+    internal();
+};
+
+destination catchall {
+	pipe("/dev/stdout");
+};
+
+log {
+    source(s_local);
+    destination(catchall);
+};