build: allow overriding GLUON_SITE_VERSION (#3091)

In case a community does not use Git for versioning it's site or using a
different versioning scheme that do not have annotated tags on the
master branch.

Signed-off-by: David Bauer <mail@david-bauer.net>

Makefile

@@ -54,7 +54,9 @@ $(eval $(call mkabspath,GLUON_TARGETSDIR))
 $(eval $(call mkabspath,GLUON_PATCHESDIR))
 
 GLUON_VERSION := $(shell scripts/getversion.sh '.')
-GLUON_SITE_VERSION := $(shell scripts/getversion.sh '$(GLUON_SITEDIR)')
+
+# Set default SITE_VERSION if not set by user
+GLUON_SITE_VERSION ?= $(shell scripts/getversion.sh '$(GLUON_SITEDIR)')
 
 GLUON_MULTIDOMAIN ?= 0
 GLUON_AUTOREMOVE ?= 0

docs/user/getting_started.rst

@@ -237,6 +237,11 @@ GLUON_RELEASE
   is available. The same GLUON_RELEASE has to be passed to ``make`` and ``make manifest``
   to generate a correct manifest.
 
+GLUON_SITE_VERSION
+  Version of the site configuration. This string is displayed in the config mode
+  and `gluon-info`. If unset, Gluon generates a version string using `git describe`
+  on the site folder.
+
 GLUON_TARGET
   Target architecture to build.