From: Xavi Leon <xleon@ac.upc.edu>
Date: Mon, 7 Nov 2011 22:52:26 +0000 (-0500)
Subject: New file sliver_libvirt. Basic code to create, start and check if it's running. Destr... 
X-Git-Tag: lxcbuild~11
X-Git-Url: http://git.onelab.eu/?a=commitdiff_plain;ds=sidebyside;h=77e2a0332809b5696394ac6fec98ae6198f00060;p=nodemanager.git

New file sliver_libvirt. Basic code to create, start and check if it's running. Destroy and stop never called. New sliver tag, type = sliver.LIBVIRT
---

diff --git a/sliver_libvirt.py b/sliver_libvirt.py
new file mode 100644
index 0000000..de7fedc
--- /dev/null
+++ b/sliver_libvirt.py
@@ -0,0 +1,165 @@
+#
+
+"""LibVirt slivers"""
+
+import accounts
+import logger
+import subprocess
+import os
+import libvirt
+import sys
+
+states = {
+    libvirt.VIR_DOMAIN_NOSTATE: 'no state',
+    libvirt.VIR_DOMAIN_RUNNING: 'running',
+    libvirt.VIR_DOMAIN_BLOCKED: 'blocked on resource',
+    libvirt.VIR_DOMAIN_PAUSED: 'paused by user',
+    libvirt.VIR_DOMAIN_SHUTDOWN: 'being shut down',
+    libvirt.VIR_DOMAIN_SHUTOFF: 'shut off',
+    libvirt.VIR_DOMAIN_CRASHED: 'crashed',
+}
+
+class Sliver_LV(accounts.Account):
+    """This class wraps LibVirt commands"""
+   
+    SHELL = '/bin/sh' 
+    # Using /bin/bash triggers destroy root/site_admin (?!?)
+    TYPE = 'sliver.LIBVIRT'
+    # Need to add a tag at myplc to actually use this account
+    # type = 'sliver.LIBVIRT'
+
+    def __init__(self, rec):
+        self.name = rec['name']
+        print "LIBVIRT %s __init__"%(self.name)
+        logger.verbose ('sliver_libvirt: %s init'%(self.name))
+         
+        self.dir = '/vservers/%s'%(self.name)
+        
+        # Assume the directory with the image and config files
+        # are in place
+        
+        self.config = '%s/config.xml'%(self.dir)
+        self.lxc_log  = '%s/log'%(self.dir)
+        self.keys = ''
+        self.rspec = {}
+        self.slice_id = rec['slice_id']
+        self.disk_usage_initialized = False
+        self.initscript = ''
+        self.enabled = True
+        conn = Sliver_LV.getConnection()
+        try:
+            self.container = conn.lookupByName(self.name)
+        except:
+            print "Unexpected error:", sys.exc_info()[0]
+
+    @staticmethod
+    def create(name, rec = None):
+        ''' Create dirs, copy fs image, lxc_create '''
+        print "LIBVIRT %s create"%(name)
+        logger.verbose ('sliver_libvirt: %s create'%(name))
+        dir = '/vservers/%s'%(name)
+        config = '%s/config.xml'%(dir)
+        lxc_log = '%s/log'%(dir)
+        
+        if not (os.path.isdir(dir) and 
+            os.access(dir, os.R_OK | os.W_OK | os.X_OK)):
+            logger.verbose('lxc_create: directory %s does not exist or wrong perms'%(dir))
+            return
+       
+        # Get a connection and lookup for the sliver before actually
+        # defining it, just in case it was already defined.
+        conn = Sliver_LV.getConnection()
+        try:
+            dom = conn.lookupByName(name)
+        except:
+            xml = open(config).read()  
+            dom = conn.defineXML(xml)
+        print Sliver_LV.info(dom)
+
+    @staticmethod
+    def destroy(name):
+        ''' NEVER CALLED... Figure out when and what to do... '''
+        
+        print "LIBVIRT %s destroy"%(name)
+        logger.verbose ('sliver_libvirt: %s destroy'%(name))
+        
+        dir = '/vservers/%s'%(name)
+        lxc_log = '%s/lxc.log'%(dir)
+
+        conn = conn.Sliver_LV.getConnection()
+
+        try:
+            dom = conn.lookupByName(name)
+            conn.destroy(dom)
+            conn.undefine(dom)
+            print Sliver_LV.info(dom)
+        except:
+            logger.verbose('sliver_libvirt: %s domain does not exists'%(name))
+            print "Unexpected error:", sys.exc_info()[0]
+
+
+    def configure(self, rec):
+        ''' Allocate resources and fancy configuration stuff '''
+        print "LIBVIRT %s configure"%(self.name) 
+        logger.verbose('sliver_libvirt: %s configure'%(self.name)) 
+
+    def start(self, delay=0):
+        ''' Just start the sliver '''
+        print "LIBVIRT %s start"%(self.name)
+        if self.rspec['enabled'] <= 0:
+            logger.log('sliver_libvirt: not starting %s, is not enabled'%(self.name))
+            return
+        else:
+            logger.log('sliver_libvirt: %s starting...' % (self.name))
+
+        # Check if it's running to avoid throwing an exception if the
+        # domain was already running, create actually means start
+        if not self.is_running():
+            self.container.create()
+        else:
+            logger.verbose('sliver_libvirt: sliver %s already started'%(self.name))
+            
+    def stop(self):
+        ''' NEVER CALLED... Figure out when and what to do... '''
+        
+        print "LIBVIRT %s stop"%(self.name)
+        logger.verbose('sliver_libvirt: %s stop'%(self.name))
+        
+        try:
+            self.container.destroy()
+        except:
+            print "Unexpected error:", sys.exc_info()[0]
+    
+    def is_running(self):
+        ''' Return True if the domain is running '''
+        print "LIBVIRT %s is_running"%(self.name)
+        logger.verbose('sliver_libvirt: %s is_running'%(self.name))
+        try:
+            [state, _, _, _, _] = self.container.info()
+            if state == libvirt.VIR_DOMAIN_RUNNING:
+                logger.verbose('sliver_libvirt: %s is RUNNING'%(self.name))
+                return True
+            else:
+                info = Sliver_LV.info(self.container)
+                logger.verbose('sliver_libvirt: %s is NOT RUNNING...\n%s'%(self.name, info))
+                return False
+        except:
+            print "Unexpected error:", sys.exc_info()
+
+    ''' PRIVATE/HELPER/STATIC METHODS '''
+    @staticmethod
+    def getConnection():
+        ''' Helper method to get a connection to the LXC driver of Libvirt '''
+        conn = libvirt.open('lxc:///')
+        if conn == None:
+            print 'Failed to open connection to LXC hypervisor'
+            sys.exit(1)
+        else: return conn
+
+    @staticmethod
+    def info(dom):
+        ''' Helper method to get a "nice" output of the info struct for debug'''
+        [state, maxmem, mem, ncpu, cputime] = dom.info()
+        return '%s is %s, maxmem = %s, mem = %s, ncpu = %s, cputime = %s' % (dom.name(), states.get(state, state), maxmem, mem, ncpu, cputime)
+
+