From ac32a7847ed26019377496b0849df5127f3b479b Mon Sep 17 00:00:00 2001
From: Thierry Parmentelat <thierry.parmentelat@sophia.inria.fr>
Date: Fri, 21 Mar 2008 16:35:32 +0000
Subject: [PATCH] support for multiple slice reference images

* vserver-reference rpm names have changed and become
    vserver-@pldistro@-@fcdistro@-@arch@
    vserver-systemslices-@pldistro@-@fcdistro@-@arch@

* this contains the images located as
   /vservers/.vref/@pldistro@-@fcdistro@-@arch@
and
  /vservers/.vstub/@pldistro@-@fcdistro@-@arch@/planetflow
respectively

* a stamp gets created on the nodes as /etc/planetlab/defaultvref
  that contains the name for the default slicefamily to use

* nodemanager tries to be smart when chosing the right argument to pass to vuseradd
  for this purpose, the argument in 'vref' is taken as a dash-separated list of 'wishes'
  so e.g. is defaultvref is planetlab-f8-x86_64, then we should find for the image name:
vref=i386           -> vuseradd -t planetlab-f8-i386
vref=centos5        -> vuseradd -t planetlab-centos5-x86_64
vref=planetflow     -> vuseradd -t planetflow
vref=centos5-onelab -> vuseradd -t onelab-centos5-x86_64

for legacy reasons, if the stamp is not found, 'default' is taken instead

=== status
* this is only partly tested
* a given node can install several variants of vserver-*
  this would require a manual upload of the rpms into the right install-rpms
  and manual changes in yumgroups.
* next improvement would be to have the system (planetflow) slices have a smarter naming scheme as well
  this way a 'planetflow' vref would rather be rewritten as planetflow-f8-x86_64
  for the time being it is not supported to install several variants of vserver-systemslices
  on the node - although it should be harmless
---
 NodeManager.spec |  4 +++-
 sliver_vs.py     | 55 +++++++++++++++++++++++++++++++++++++++++++-----
 2 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/NodeManager.spec b/NodeManager.spec
index f02dd37..fcf3bc6 100644
--- a/NodeManager.spec
+++ b/NodeManager.spec
@@ -3,6 +3,8 @@
 #
 %define url $URL$
 
+%define slicefamily %{pldistro}-%{distroname}-%{_arch}
+
 %define name NodeManager
 %define version 1.7
 %define taglevel 2
@@ -27,7 +29,7 @@ URL: %(echo %{url} | cut -d ' ' -f 2)
 Obsoletes: sidewinder, sidewinder-common
 
 # vuseradd, vuserdel
-Requires: vserver-reference
+Requires: vserver-%{slicefamily}
 Requires: util-vserver >= 0.30.208-17
 
 # vserver.py
diff --git a/sliver_vs.py b/sliver_vs.py
index 2f183c8..ca5d144 100644
--- a/sliver_vs.py
+++ b/sliver_vs.py
@@ -17,7 +17,7 @@ don't have to guess if there is a running process or not.
 """
 
 import errno
-import os
+import os, os.path
 import time
 import vserver
 
@@ -67,10 +67,55 @@ class Sliver_VS(accounts.Account, vserver.VServer):
     @staticmethod
     def create(name, vref = None):
         logger.verbose('Sliver_VS:create - name=%s'%name)
-        if vref is not None:
-            logger.log_call('/usr/sbin/vuseradd', '-t', vref, name)
-        else:
-            logger.log_call('/usr/sbin/vuseradd', name)
+        if vref is None:
+            vref='default'
+        try:
+            ### locating the right slicefamily
+            # this is a first draft, and more a proof of concept thing
+            # the idea is to parse vref for dash-separated wishes,
+            # and to project these against the defaults
+            # however for cases like when vref is 'planetflow', if we do not understand
+            # any of the wishes we take vref as is
+            # this could be improved by having the vserver-reference init script be a bit smarter
+            # so we could take planetflow as the pldistro part here
+            as_is=None
+            # defaults
+            default=file("/etc/planetlab/defaultvref").read()
+            (pldistro,fcdistro,arch) = default.split("-")
+            # from the slice attribute: cut dashes and try to figure the meaning
+            slice_wishes = vref.split("-")
+            for wish in slice_wishes:
+                if wish == "i386" or wish == "x86_64":
+                    arch=wish
+                elif wish == "planetlab" or wish == "onelab" or wish == "vini":
+                    pldistro=wish
+                elif wish == "f8" or wish == "centos5" :
+                    fcdistro=wish
+                else:
+                    # if we find something like e.g. planetflow, use it as-is
+                    as_is=vref
+                    break
+            if as_is:
+                refname=as_is
+            else:
+                refname="-".join( (pldistro,fcdistro,arch) )
+            # check the templates exists -- there's probably a better way..
+            if not os.path.isdir ("/vservers/.vref/%s"%refname):
+                log.verbose("%s (%s) : vref %s not found, using default %s"%(
+                        name,vref,refname,default))
+                refname=default
+            except IOError:
+                # have not found defaultvref
+                logger.verbose("%s (%s): using fallback vrefname 'default'"%(name,vref))
+                # for legacy nodes
+                refname="default"
+            except:
+                import traceback
+                logger.log("%s (%s) : unexpected error follows - using 'default'"%(
+                        name,vref))
+                logger.log(traceback.format_exc())
+            
+            logger.log_call('/usr/sbin/vuseradd', '-t', refname, name)
         open('/vservers/%s/etc/slicename' % name, 'w').write(name)
 
     @staticmethod
-- 
2.43.0