Switch to dnf when it exists
This has all been around for a *long* time, like when dnf was a weird
new thing. Now it's the opposite and yum is a weird old thing :)
Choose it by default for platforms with it (Fedora, for now).
Change-Id: Id2bd7d145354b996de31944929fd0267ec24a08e
diff --git a/stackrc b/stackrc
index 3c4e437..66d6f23 100644
--- a/stackrc
+++ b/stackrc
@@ -819,11 +819,14 @@
# Service graceful shutdown timeout
WORKER_TIMEOUT=${WORKER_TIMEOUT:-90}
-# Support alternative yum -- in future Fedora 'dnf' will become the
-# only supported installer, but for now 'yum' and 'dnf' are both
-# available in parallel with compatible CLIs. Allow manual switching
-# till we get to the point we need to handle this automatically
-YUM=${YUM:-yum}
+# Choose DNF on RedHat/Fedora platforms with it, or otherwise default
+# to YUM. Can remove this when only dnf is supported (i.e. centos7
+# disappears)
+if [[ -e /usr/bin/dnf ]]; then
+ YUM=${YUM:-dnf}
+else
+ YUM=${YUM:-yum}
+fi
# Common Configuration
# --------------------