Many more improvements.

util/vm/build.py

@@ -46,13 +46,16 @@
 
 
 import os
+from os import stat
+from stat import ST_MODE
 from os.path import exists, splitext
+from sys import exit, argv
 from glob import glob
 from urllib import urlretrieve
 from subprocess import check_output, call, Popen, PIPE
 from tempfile import mkdtemp, NamedTemporaryFile
-from sys import exit
 from time import time
+import argparse
 
 # boot can be slooooow!!!! need to debug/optimize somehow
 TIMEOUT=600
@@ -60,7 +63,10 @@
 VMImageDir = os.environ[ 'HOME' ] + '/vm-images'
 
 ImageURLBase = {
-    'raring-server-amd64':
+    'raring32server':
+    'http://cloud-images.ubuntu.com/raring/current/'
+    'raring-server-cloudimg-i386',
+    'raring64server':
     'http://cloud-images.ubuntu.com/raring/current/'
     'raring-server-cloudimg-amd64'
 }
@@ -78,17 +84,17 @@ def srun( cmd, **kwargs ):
     return run( 'sudo ' + cmd, **kwargs )
 
 
-# Install necessary packages
-print '* Installing package dependencies'
-packages = ( )
-run( 'sudo apt-get -y update' )
-run( 'sudo apt-get install -y'
-     ' kvm cloud-utils genisoimage qemu-kvm qemu-utils'
-     ' e2fsprogs '
-     ' landscape-client'
-     ' python-setuptools' )
-run( 'sudo easy_install pexpect' )
-import pexpect
+def depend():
+    "Install packagedependencies"
+    print '* Installing package dependencies'
+    packages = ( )
+    run( 'sudo apt-get -y update' )
+    run( 'sudo apt-get install -y'
+         ' kvm cloud-utils genisoimage qemu-kvm qemu-utils'
+         ' e2fsprogs '
+         ' landscape-client'
+         ' python-setuptools' )
+    run( 'sudo easy_install pexpect' )
 
 
 def popen( cmd ):
@@ -127,6 +133,11 @@ def fetchImage( image, path=None ):
     floppy = path + '-floppy'
     if exists( disk ) and exists( kernel ):
         print '* Found', disk, 'and', kernel
+        # Detect race condition with multiple builds
+        perms = stat( disk )[ ST_MODE ] & 0777
+        if perms != 0444:
+            raise Exception( 'Error - %s is writable ' % disk +
+                             '; are multiple builds running?' )
     else:
         dir = os.path.dirname( path )
         run( 'mkdir -p %s' % dir )
@@ -136,13 +147,10 @@ def fetchImage( image, path=None ):
             urlretrieve( url, tgz )
         print '* Extracting', tgz
         run( 'tar -C %s -xzf %s' % ( dir, tgz ) )
-    # Make sure Mininet user is there
-    os.chmod( disk, 0664 )
-    addMininetUser( disk )
-    # Write-protect disk image so it remains somewhat pristine;
-    # We will not use it directly but will use a COW disk
-    print '* Write-protecting disk image', disk
-    os.chmod( disk, 0444 )
+        # Write-protect disk image so it remains pristine;
+        # We will not use it directly but will use a COW disk
+        print '* Write-protecting disk image', disk
+        os.chmod( disk, 0444 )
     return disk, kernel
 
 
@@ -162,14 +170,14 @@ def disableCloud( bind ):
         call( 'echo manual | sudo tee ' + override, shell=True )
 
 
-def addMininetUser( img ):
-    "Add mininet user/group to root filesystem image"
-    print '* Adding mininet user to', img
+def addMininetUser( nbd ):
+    "Add mininet user/group to filesystem"
+    print '* Adding mininet user to filesystem on device', nbd
     # 1. We bind-mount / into a temporary directory, and
     # then mount the volume's /etc and /home on top of it!
     mnt = mkdtemp()
     bind = mkdtemp()
-    srun( 'mount %s %s' % ( img, mnt ) )
+    srun( 'mount %s %s' % ( nbd, mnt ) )
     srun( 'mount -B / ' + bind )
     srun( 'mount -B %s/etc %s/etc' % ( mnt, bind ) )
     srun( 'mount -B %s/home %s/home' % ( mnt, bind ) )
@@ -202,66 +210,79 @@ def chroot( cmd ):
     run( 'rmdir ' + bind )
     run( 'rmdir ' + mnt )
     # 4. Just to make sure, we check the filesystem
-    run( 'e2fsck -y ' + img )
+    srun( 'e2fsck -y ' + nbd )
+
+
+def connectCOWdevice( cow ):
+    "Attempt to connect a COW disk and return its nbd device"
+    print '* Checking for unused /dev/nbdX device ',
+    for i in range ( 0, 63 ):
+        nbd = '/dev/nbd%d' % i
+        print i,
+        # Check whether someone's already messing with that device
+        if call( [ 'pgrep', '-f', nbd ] ) == 0:
+            continue
+        # Fails without -v for some annoying reason...
+        print
+        srun( 'qemu-nbd -c %s %s' % ( nbd, cow ) )
+        return nbd
+    raise Exception( "Error: could not find unused /dev/nbdX device" )
+
+
+def disconnectCOWdevice( nbd ):
+    srun( 'qemu-nbd -d ' + nbd )
 
 
 def makeCOWDisk( image ):
     "Create new COW disk for image"
     disk, kernel = fetchImage( image )
-    cow = disk + '.qcow2'
+    cow = NamedTemporaryFile( prefix=image + '-', suffix='.qcow2',
+                              dir='.' ).name
     print '* Creating COW disk', cow
-    remove( cow )
     run( 'qemu-img create -f qcow2 -b %s %s' % ( disk, cow ) )
     print '* Resizing COW disk and file system'
     run( 'qemu-img resize %s +8G' % cow )
-    srun( 'modprobe nbd')
-    # Ideally we should check if it's being used...
-    srun( 'qemu-nbd -d /dev/nbd0' )
-    srun( 'qemu-nbd -c /dev/nbd0 ' + cow )
-    srun( 'e2fsck -fy /dev/nbd0' )
-    srun( 'resize2fs /dev/nbd0' )
-    srun( 'qemu-nbd -d /dev/nbd0' )
+    srun( 'modprobe nbd max-part=64')
+    nbd = connectCOWdevice( cow )
+    srun( 'e2fsck -y ' + nbd )
+    srun( 'resize2fs ' + nbd )
+    addMininetUser( nbd )
+    disconnectCOWdevice( nbd )
     return cow, kernel
 
 
-def boot( cow, kernel ):
+def boot( cow, kernel, tap ):
     """Boot qemu/kvm with a COW disk and local/user data store
-       returns: popen object to qemu process"""
-    if 'amd64' in cow:
+       cow: COW disk path
+       kernel: kernel path
+       tap: tap device to connect to VM
+       returns: pexpect object to qemu process"""
+    # pexpect might not be installed until after depend() is called
+    global pexpect
+    import pexpect
+    if 'amd64' in kernel:
         kvm = 'qemu-system-x86_64'
-    elif 'i386' in cow:
+    elif 'i386' in kernel:
         kvm = 'qemu-system-i386'
     else:
         print "Error: can't discern CPU for image", cow
-        exit
-    # was -nographic
-    # was -net=%net
-    #             ' -net nic,model=virtio'
-    #             ' -netdev tap,id=mininet0,ifname=%s,script=no ' % tap +
+        exit( 1 )
     cmd = [ 'sudo', kvm,
-            '-machine', 'accel=kvm',
+            '-machine accel=kvm',
             '-nographic',
-            '-m', '512',
-            '-k',  'en-us',
+            '-netdev user,id=mnbuild',
+            '-device virtio-net,netdev=mnbuild',
+            '-m 1024',
+            '-k en-us',
             '-kernel', kernel,
-            '-drive',  'file=%s,if=virtio' % cow,
-            '-append',
-            ' "root=/dev/vda'
-            ' init=/sbin/init'
-#            ' init=/usr/lib/cloud-init/uncloud-init'
-#            ' ds=nocloud'
-#            ' --verbose'
-            ' console=ttyS0"'
-           ]
-
+            '-drive file=%s,if=virtio' % cow,
+            '-append "root=/dev/vda init=/sbin/init console=ttyS0" ' ]
     cmd = ' '.join( cmd )
     print '* STARTING VM'
     print cmd
     vm = pexpect.spawn( cmd, timeout=TIMEOUT )
-    logfile = NamedTemporaryFile( prefix='mn-build-expect' )
-    print '* Logging results to', logfile.name
-    vm.logfile_read = logfile
-    return vm, logfile
+    return vm
+
 
 def interact( vm ):
     "Interact with vm, which is a pexpect object"
@@ -288,7 +309,8 @@ def interact( vm ):
     print '* Running VM install script'
     vm.sendline( 'bash install-mininet-vm.sh' )
     print '* Waiting for script to complete... '
-    vm.expect( 'Done preparing Mininet' )
+    # Gigantic timeout for now ;-(
+    vm.expect( 'Done preparing Mininet', timeout=3600 )
     print '* Completed successfully'
     vm.expect( prompt )
     print '* Testing Mininet'
@@ -312,18 +334,74 @@ def interact( vm ):
     vm.read()
     print '* Interaction complete'
 
-image = 'raring-server-amd64'
-
-start = time()
-cow, kernel = makeCOWDisk( image )
-print '* VM image for', image, 'created as', cow
-vm, logfile = boot( cow, kernel )
-interact( vm )
-logfile.close()
-end = time()
-elapsed = end - start
-print '* Results logged to', logfile.name
-print '* Completed in %.2f seconds' % elapsed
-print '* DONE!!!!! :D'
-
 
+def cleanup():
+    "Clean up leftover qemu-nbd processes and other junk"
+    call( 'sudo pkill -9 qemu-nbd', shell=True )
+
+
+def convert( cow, basename ):
+    """Convert a qcow2 disk to a vmdk and put it a new directory
+       basename: base name for output vmdk file"""
+    dir = mkdtemp( prefix=basename, dir='.' )
+    vmdk = '%s/%s.vmdk' % ( dir, basename )
+    print '* Converting qcow2 to vmdk'
+    run( 'qemu-img convert -f qcow2 -O vmdk %s %s' % ( cow, vmdk ) )
+    return vmdk
+
+
+def build( flavor='raring-server-amd64' ):
+    "Build a Mininet VM"
+    start = time()
+    cow, kernel = makeCOWDisk( flavor )
+    print '* VM image for', flavor, 'created as', cow
+    with NamedTemporaryFile(
+        prefix='mn-build-%s-' % flavor, suffix='.log', dir='.' ) as logfile:
+        print '* Logging results to', logfile.name
+        vm = boot( cow, kernel, logfile )
+        vm.logfile_read = logfile
+        interact( vm )
+    # cow is a temporary file and will go away when we quit!
+    # We convert it to a .vmdk which can be used in most VMMs
+    vmdk = convert( cow, basename=flavor )
+    print '* Converted VM image stored as', vmdk
+    end = time()
+    elapsed = end - start
+    print '* Results logged to', logfile.name
+    print '* Completed in %.2f seconds' % elapsed
+    print '* %s VM build DONE!!!!! :D' % flavor
+    print
+
+
+def parseArgs():
+    "Parse command line arguments and run"
+    parser = argparse.ArgumentParser( description='Mininet VM build script' )
+    parser.add_argument( '--depend', action='store_true',
+                         help='Install dependencies for this script' )
+    parser.add_argument( '--list', action='store_true',
+                         help='list valid build flavors' )
+    parser.add_argument( '--clean', action='store_true',
+                         help='clean up leftover build junk (e.g. qemu-nbd)' )
+    parser.add_argument( 'flavor', nargs='*',
+                         help='VM flavor to build (e.g. raring32server)' )
+    args = parser.parse_args( argv )
+    if args.depend:
+        depend()
+    if args.list:
+        print 'valid build flavors:', ' '.join( ImageURLBase )
+    if args.clean:
+        cleanup()
+    flavors = args.flavor[ 1: ]
+    for flavor in flavors:
+        if flavor not in ImageURLBase:
+            parser.print_help()
+        # try:
+        build( flavor )
+        # except Exception as e:
+        # print '* BUILD FAILED with exception: ', e
+        # exit( 1 )
+    if not ( args.depend or args.list or args.clean or flavors ):
+        parser.print_help()
+
+if __name__ == '__main__':
+    parseArgs()