Merge pull request #39 from stackhpc/feature/etc-hosts

Adds etc-hosts element

Author: Alex-Welsh

elements/etc-hosts/README.rst

@@ -0,0 +1,16 @@
+=========
+etc-hosts
+=========
+Appends text to /etc/hosts.
+
+`DIB_ETC_HOSTS_EXTRA`: Lines to add to /etc/hosts
+
+For example:
+
+  .. code-block::
+
+   export DIB_ETC_HOSTS_EXTRA="192.168.20.1 compute-host-01"
+
+Or:
+
+   export DIB_ETC_HOSTS_EXTRA=`cat ./my-hosts`

elements/etc-hosts/environment.d/etc-hosts

@@ -0,0 +1,3 @@
+#!/bin/bash
+
+export ETC_HOSTS_EXTRA=${DIB_ETC_HOSTS_EXTRA:?"You must define DIB_ETC_HOSTS_EXTRA"}

elements/etc-hosts/pre-install.d/01-etc-hosts

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+if [ ${DIB_DEBUG_TRACE:-1} -gt 0 ]; then
+    set -x
+fi
+set -eu
+set -o pipefail
+
+printf "$ETC_HOSTS_EXTRA" >> /etc/hosts