Replace 'megabyte' with 'MiB' to please Anders.

[invirt/packages/invirt-web.git] / templates / main.py

diff --git a/templates/main.py b/templates/main.py
index d4ac4e6..0bf16b9 100755 (executable)
--- a/templates/main.py
+++ b/templates/main.py
@@ -1,249 +1,604 @@
 #!/usr/bin/python
 #!/usr/bin/python

+"""Main CGI script for web interface"""

 
 

-import sys
+import base64
+import cPickle

 import cgi
 import cgi

+import datetime
+import hmac

 import os
 import os

-import string
-import subprocess
+import sha
+import simplejson
+import sys
+import time
+from StringIO import StringIO
+
+
+def revertStandardError():
+    """Move stderr to stdout, and return the contents of the old stderr."""
+    errio = sys.stderr
+    if not isinstance(errio, StringIO):
+        return None
+    sys.stderr = sys.stdout
+    errio.seek(0)
+    return errio.read()
+
+def printError():
+    """Revert stderr to stdout, and print the contents of stderr"""
+    if isinstance(sys.stderr, StringIO):
+        print revertStandardError()
+
+if __name__ == '__main__':
+    import atexit
+    atexit.register(printError)
+    sys.stderr = StringIO()

 
 

-print 'Content-Type: text/html\n'
-sys.stderr = sys.stdout

 sys.path.append('/home/ecprice/.local/lib/python2.5/site-packages')
 
 from Cheetah.Template import Template
 sys.path.append('/home/ecprice/.local/lib/python2.5/site-packages')
 
 from Cheetah.Template import Template

-from sipb_xen_database import *
-import random
+from sipb_xen_database import Machine, CDROM, ctx, connect
+import validation
+from webcommon import InvalidInput, CodeError, g
+import controls

 
 

-# ... and stolen from xend/uuid.py
-def randomUUID():
-    """Generate a random UUID."""
+def helppopup(subj):
+    """Return HTML code for a (?) link to a specified help topic"""
+    return ('<span class="helplink"><a href="help?subject=' + subj + 
+            '&amp;simple=true" target="_blank" ' + 
+            'onclick="return helppopup(\'' + subj + '\')">(?)</a></span>')

 
 

-    return [ random.randint(0, 255) for _ in range(0, 16) ]
+def makeErrorPre(old, addition):
+    if addition is None:
+        return
+    if old:
+        return old[:-6]  + '\n----\n' + str(addition) + '</pre>'
+    else:
+        return '<p>STDERR:</p><pre>' + str(addition) + '</pre>'

 
 

-def uuidToString(u):
-    return "-".join(["%02x" * 4, "%02x" * 2, "%02x" * 2, "%02x" * 2,
-                     "%02x" * 6]) % tuple(u)
+Template.helppopup = staticmethod(helppopup)
+Template.err = None

 
 

+class JsonDict:
+    """Class to store a dictionary that will be converted to JSON"""
+    def __init__(self, **kws):
+        self.data = kws
+        if 'err' in kws:
+            err = kws['err']
+            del kws['err']
+            self.addError(err)

 
 

-def maxMemory(user):
-    return 256
+    def __str__(self):
+        return simplejson.dumps(self.data)

 
 

-def haveAccess(user, machine):
-    return True
+    def addError(self, text):
+        """Add stderr text to be displayed on the website."""
+        self.data['err'] = \
+            makeErrorPre(self.data.get('err'), text)

 
 

+class Defaults:
+    """Class to store default values for fields."""
+    memory = 256
+    disk = 4.0
+    cdrom = ''
+    name = ''
+    vmtype = 'hvm'
+    def __init__(self, max_memory=None, max_disk=None, **kws):
+        if max_memory is not None:
+            self.memory = min(self.memory, max_memory)
+        if max_disk is not None:
+            self.max_disk = min(self.disk, max_disk)
+        for key in kws:
+            setattr(self, key, kws[key])

 
 

-def error(op, user, fields, errorMessage):
-    d = dict(op=op,
-             user=user,
-             errorMessage=errorMessage)
-    print Template(file='error.tmpl',
-                   searchList=d);

 
 

-def validMachineName(name):
-    if not name:
-        return False
-    charset = string.ascii_letters + string.digits + '-'
-    if name[0] == '-' or len(name) > 22:
-        return False
-    return all(x in charset for x in name)
-
-def kinit():
-    keytab = '/etc/tabbott.keytab'
-    username = 'tabbott/extra'
-    p = subprocess.Popen(['kinit', "-k", "-t", keytab, 
-                          username])
-    p.wait()
-
-def checkKinit():
-    p = subprocess.Popen(['klist', '-s'])
-    if p.wait():
-        kinit()
-
-def remctl(*args):
-    checkKinit()
-    p = subprocess.Popen(['remctl', 'black-mesa.mit.edu']
-                         + list(args),
-                         stdout=subprocess.PIPE,
-                         stderr=subprocess.PIPE)
-    if p.wait():
-        print >> sys.stderr, 'ERROR on remctl ', args
-        print >> sys.stderr, p.stderr.read()
-
-def makeDisks():
-    remctl('lvcreate','all')
-
-def bootMachine(machine, cdtype):
-    if cdtype is not None:
-        remctl('vmboot', 'cdrom', str(machine.name),
-               cdtype)
-    else:
-        remctl('vmboot', 'cdrom', str(machine.name))

 
 

-def createVm(user, name, memory, disk, is_hvm, cdrom):
-    # put stuff in the table
-    transaction = ctx.current.create_transaction()
-    try:
-        res = meta.engine.execute('select nextval(\'"machines_machine_id_seq"\')')
-        id = res.fetchone()[0]
-        machine = Machine()
-        machine.machine_id = id
-        machine.name = name
-        machine.memory = memory
-        machine.owner = user.username
-        machine.contact = user.email
-        machine.uuid = uuidToString(randomUUID())
-        machine.boot_off_cd = True
-        machine_type = Type.get_by(hvm=is_hvm)
-        machine.type_id = machine_type.type_id
-        ctx.current.save(machine)
-        disk = Disk(machine.machine_id, 
-                    'hda', disk)
-        open = NIC.select_by(machine_id=None)
-        if not open: #No IPs left!
-            return "No IP addresses left!  Contact sipb-xen-dev@mit.edu"
-        nic = open[0]
-        nic.machine_id = machine.machine_id
-        nic.hostname = name
-        ctx.current.save(nic)    
-        ctx.current.save(disk)
-        transaction.commit()
-    except:
-        transaction.rollback()
-        raise
-    makeDisks()
-    # tell it to boot with cdrom
-    bootMachine(machine, cdrom)
+DEFAULT_HEADERS = {'Content-Type': 'text/html'}

 
 

-    return machine
+def error(op, user, fields, err, emsg):
+    """Print an error page when a CodeError occurs"""
+    d = dict(op=op, user=user, errorMessage=str(err),
+             stderr=emsg)
+    return Template(file='error.tmpl', searchList=[d])

 
 

-def create(user, fields):
+def invalidInput(op, user, fields, err, emsg):
+    """Print an error page when an InvalidInput exception occurs"""
+    d = dict(op=op, user=user, err_field=err.err_field,
+             err_value=str(err.err_value), stderr=emsg,
+             errorMessage=str(err))
+    return Template(file='invalid.tmpl', searchList=[d])
+
+def hasVnc(status):
+    """Does the machine with a given status list support VNC?"""
+    if status is None:
+        return False
+    for l in status:
+        if l[0] == 'device' and l[1][0] == 'vfb':
+            d = dict(l[1][1:])
+            return 'location' in d
+    return False
+
+def parseCreate(user, fields):

     name = fields.getfirst('name')
     name = fields.getfirst('name')

-    if not validMachineName(name):
-        return error('create', user, fields,
-                     "Invalid name '%s'" % name)
+    if not validation.validMachineName(name):
+        raise InvalidInput('name', name, 'You must provide a machine name.')

     name = name.lower()
 
     if Machine.get_by(name=name):
     name = name.lower()
 
     if Machine.get_by(name=name):

-        return error('create', user, fields,
-                     "A machine named '%s' already exists" % name)
+        raise InvalidInput('name', name,
+                           "Name already exists.")

     
     

+    owner = validation.testOwner(user, fields.getfirst('owner'))
+

     memory = fields.getfirst('memory')
     memory = fields.getfirst('memory')

-    try:
-        memory = int(memory)
-        if memory <= 0:
-            raise ValueError
-    except ValueError:
-        return error('create', user, fields,
-                     "Invalid memory amount")
-    if memory > maxMemory(user):
-        return error('create', user, fields,
-                     "Too much memory requested")
+    memory = validation.validMemory(user, memory, on=True)

     
     disk = fields.getfirst('disk')
     
     disk = fields.getfirst('disk')

-    try:
-        disk = float(disk)
-        disk = int(disk * 1024)
-        if disk <= 0:
-            raise ValueError
-    except ValueError:
-        return error('create', user, fields,
-                     "Invalid disk amount")
-    
+    disk = validation.validDisk(user, disk)
+

     vm_type = fields.getfirst('vmtype')
     if vm_type not in ('hvm', 'paravm'):
     vm_type = fields.getfirst('vmtype')
     if vm_type not in ('hvm', 'paravm'):

-        return error('create', user, fields,
-                     "Invalid vm type '%s'"  % vm_type)    
+        raise CodeError("Invalid vm type '%s'"  % vm_type)    

     is_hvm = (vm_type == 'hvm')
 
     cdrom = fields.getfirst('cdrom')
     if cdrom is not None and not CDROM.get(cdrom):
     is_hvm = (vm_type == 'hvm')
 
     cdrom = fields.getfirst('cdrom')
     if cdrom is not None and not CDROM.get(cdrom):

-        return error('create', user, fields,
-                     "Invalid cdrom type '%s'" % cdrom)    
-    
-    machine = createVm(user, name, memory, disk, is_hvm, cdrom)
-    if isinstance(machine, basestring):
-        return error('create', user, fields,
-                     machine)
-    d = dict(user=user,
-             machine=machine)
-    print Template(file='create.tmpl',
-                   searchList=d);
+        raise CodeError("Invalid cdrom type '%s'" % cdrom)
+    return dict(contact=user, name=name, memory=memory, disk=disk,
+                owner=owner, is_hvm=is_hvm, cdrom=cdrom)

 
 

-def listVms(user, fields):
-    machines = Machine.select()
+def create(user, fields):
+    """Handler for create requests."""
+    try:
+        parsed_fields = parseCreate(user, fields)
+        machine = controls.createVm(**parsed_fields)
+    except InvalidInput, err:
+        pass
+    else:
+        err = None
+    g.clear() #Changed global state
+    d = getListDict(user)
+    d['err'] = err
+    if err:
+        for field in fields.keys():
+            setattr(d['defaults'], field, fields.getfirst(field))
+    else:
+        d['new_machine'] = parsed_fields['name']
+    return Template(file='list.tmpl', searchList=[d])
+
+
+def getListDict(user):
+    machines = [m for m in Machine.select() 
+                if validation.haveAccess(user, m)]    
+    on = {}
+    has_vnc = {}
+    on = g.uptimes
+    for m in machines:
+        m.uptime = g.uptimes.get(m)
+        if not on[m]:
+            has_vnc[m] = 'Off'
+        elif m.type.hvm:
+            has_vnc[m] = True
+        else:
+            has_vnc[m] = "ParaVM"+helppopup("paravm_console")
+    max_memory = validation.maxMemory(user)
+    max_disk = validation.maxDisk(user)
+    defaults = Defaults(max_memory=max_memory,
+                        max_disk=max_disk,
+                        owner=user,
+                        cdrom='gutsy-i386')

     d = dict(user=user,
     d = dict(user=user,

+             cant_add_vm=validation.cantAddVm(user),
+             max_memory=max_memory,
+             max_disk=max_disk,
+             defaults=defaults,

              machines=machines,
              machines=machines,

+             has_vnc=has_vnc,
+             uptimes=g.uptimes,

              cdroms=CDROM.select())
              cdroms=CDROM.select())

+    return d
+
+def listVms(user, fields):
+    """Handler for list requests."""
+    d = getListDict(user)
+    return Template(file='list.tmpl', searchList=[d])
+            
+def vnc(user, fields):
+    """VNC applet page.

 
 

-    print Template(file='list.tmpl', searchList=d)
+    Note that due to same-domain restrictions, the applet connects to
+    the webserver, which needs to forward those requests to the xen
+    server.  The Xen server runs another proxy that (1) authenticates
+    and (2) finds the correct port for the VM.

 
 

-def testMachineId(user, machineId, exists=True):
-    if machineId is None:
-        error('vnc', user, fields,
-              "No machine ID specified")
-        return False
-    try:
-        machineId = int(machineId)
-    except ValueError:
-        error('vnc', user, fields,
-              "Invalid machine ID '%s'" 
-              % machineId)
-        return False
-    machine = Machine.get(machineId)
-    if exists and machine is None:
-        error('vnc', user, fields,
-              "No such machine ID '%s'" 
-              % machineId)
-        return False
-    if not haveAccess(user, machine):
-        error('vnc', user, fields,
-              "No access to machine ID '%s'" 
-              % machineId)
-        return False
-    return machine
+    You might want iptables like:

 
 

-def vnc(user, fields):
-    machine = testMachineId(user, fields.getfirst('machine_id'))
-    if machine is None: #gave error page already
-        return
-    token = 'quentin'
+    -t nat -A PREROUTING -s ! 18.181.0.60 -i eth1 -p tcp -m tcp \
+      --dport 10003 -j DNAT --to-destination 18.181.0.60:10003 
+    -t nat -A POSTROUTING -d 18.181.0.60 -o eth1 -p tcp -m tcp \
+      --dport 10003 -j SNAT --to-source 18.187.7.142 
+    -A FORWARD -d 18.181.0.60 -i eth1 -o eth1 -p tcp -m tcp \
+      --dport 10003 -j ACCEPT
+
+    Remember to enable iptables!
+    echo 1 > /proc/sys/net/ipv4/ip_forward
+    """
+    machine = validation.testMachineId(user, fields.getfirst('machine_id'))
+    
+    TOKEN_KEY = "0M6W0U1IXexThi5idy8mnkqPKEq1LtEnlK/pZSn0cDrN"
+
+    data = {}
+    data["user"] = user
+    data["machine"] = machine.name
+    data["expires"] = time.time()+(5*60)
+    pickled_data = cPickle.dumps(data)
+    m = hmac.new(TOKEN_KEY, digestmod=sha)
+    m.update(pickled_data)
+    token = {'data': pickled_data, 'digest': m.digest()}
+    token = cPickle.dumps(token)
+    token = base64.urlsafe_b64encode(token)
+    
+    status = controls.statusInfo(machine)
+    has_vnc = hasVnc(status)
+    

     d = dict(user=user,
     d = dict(user=user,

+             on=status,
+             has_vnc=has_vnc,

              machine=machine,
              machine=machine,

-             hostname='localhost',
+             hostname=os.environ.get('SERVER_NAME', 'localhost'),

              authtoken=token)
              authtoken=token)

-    print Template(file='vnc.tmpl',
-                   searchList=d)
+    return Template(file='vnc.tmpl', searchList=[d])

 
 

-def info(user, fields):
-    machine = testMachineId(user, fields.getfirst('machine_id'))
-    if machine is None: #gave error page already
-        return
+def getNicInfo(data_dict, machine):
+    """Helper function for info, get data on nics for a machine.
+
+    Modifies data_dict to include the relevant data, and returns a list
+    of (key, name) pairs to display "name: data_dict[key]" to the user.
+    """
+    data_dict['num_nics'] = len(machine.nics)
+    nic_fields_template = [('nic%s_hostname', 'NIC %s Hostname'),
+                           ('nic%s_mac', 'NIC %s MAC Addr'),
+                           ('nic%s_ip', 'NIC %s IP'),
+                           ]
+    nic_fields = []
+    for i in range(len(machine.nics)):
+        nic_fields.extend([(x % i, y % i) for x, y in nic_fields_template])
+        if not i:
+            data_dict['nic%s_hostname' % i] = (machine.name + 
+                                               '.servers.csail.mit.edu')
+        data_dict['nic%s_mac' % i] = machine.nics[i].mac_addr
+        data_dict['nic%s_ip' % i] = machine.nics[i].ip
+    if len(machine.nics) == 1:
+        nic_fields = [(x, y.replace('NIC 0 ', '')) for x, y in nic_fields]
+    return nic_fields
+
+def getDiskInfo(data_dict, machine):
+    """Helper function for info, get data on disks for a machine.
+
+    Modifies data_dict to include the relevant data, and returns a list
+    of (key, name) pairs to display "name: data_dict[key]" to the user.
+    """
+    data_dict['num_disks'] = len(machine.disks)
+    disk_fields_template = [('%s_size', '%s size')]
+    disk_fields = []
+    for disk in machine.disks:
+        name = disk.guest_device_name
+        disk_fields.extend([(x % name, y % name) for x, y in 
+                            disk_fields_template])
+        data_dict['%s_size' % name] = "%0.1f GiB" % (disk.size / 1024.)
+    return disk_fields
+
+def command(user, fields):
+    """Handler for running commands like boot and delete on a VM."""
+    back = fields.getfirst('back')
+    try:
+        d = controls.commandResult(user, fields)
+        if d['command'] == 'Delete VM':
+            back = 'list'
+    except InvalidInput, err:
+        if not back:
+            raise
+        print >> sys.stderr, err
+        result = None
+    else:
+        result = 'Success!'
+        if not back:
+            return Template(file='command.tmpl', searchList=[d])
+    if back == 'list':
+        g.clear() #Changed global state
+        d = getListDict(user)
+        d['result'] = result
+        return Template(file='list.tmpl', searchList=[d])
+    elif back == 'info':
+        machine = validation.testMachineId(user, fields.getfirst('machine_id'))
+        d = infoDict(user, machine)
+        d['result'] = result
+        return Template(file='info.tmpl', searchList=[d])
+    else:
+        raise InvalidInput('back', back, 'Not a known back page.')
+
+def modifyDict(user, fields):
+    olddisk = {}
+    transaction = ctx.current.create_transaction()
+    try:
+        machine = validation.testMachineId(user, fields.getfirst('machine_id'))
+        owner = validation.testOwner(user, fields.getfirst('owner'), machine)
+        admin = validation.testAdmin(user, fields.getfirst('administrator'),
+                                     machine)
+        contact = validation.testContact(user, fields.getfirst('contact'),
+                                         machine)
+        name = validation.testName(user, fields.getfirst('name'), machine)
+        oldname = machine.name
+        command = "modify"
+
+        memory = fields.getfirst('memory')
+        if memory is not None:
+            memory = validation.validMemory(user, memory, machine, on=False)
+            machine.memory = memory
+ 
+        disksize = validation.testDisk(user, fields.getfirst('disk'))
+        if disksize is not None:
+            disksize = validation.validDisk(user, disksize, machine)
+            disk = machine.disks[0]
+            if disk.size != disksize:
+                olddisk[disk.guest_device_name] = disksize
+                disk.size = disksize
+                ctx.current.save(disk)
+        
+        if owner is not None:
+            machine.owner = owner
+        if name is not None:
+            machine.name = name
+        if admin is not None:
+            machine.administrator = admin
+        if contact is not None:
+            machine.contact = contact
+            
+        ctx.current.save(machine)
+        transaction.commit()
+    except:
+        transaction.rollback()
+        raise
+    for diskname in olddisk:
+        controls.resizeDisk(oldname, diskname, str(olddisk[diskname]))
+    if name is not None:
+        controls.renameMachine(machine, oldname, name)
+    return dict(user=user,
+                command=command,
+                machine=machine)

     
     

+def modify(user, fields):
+    """Handler for modifying attributes of a machine."""
+    try:
+        modify_dict = modifyDict(user, fields)
+    except InvalidInput, err:
+        result = None
+        machine = validation.testMachineId(user, fields.getfirst('machine_id'))
+    else:
+        machine = modify_dict['machine']
+        result = 'Success!'
+        err = None
+    info_dict = infoDict(user, machine)
+    info_dict['err'] = err
+    if err:
+        for field in fields.keys():
+            setattr(info_dict['defaults'], field, fields.getfirst(field))
+    info_dict['result'] = result
+    return Template(file='info.tmpl', searchList=[info_dict])
+    
+
+def helpHandler(user, fields):
+    """Handler for help messages."""
+    simple = fields.getfirst('simple')
+    subjects = fields.getlist('subject')
+    
+    help_mapping = dict(paravm_console="""
+ParaVM machines do not support console access over VNC.  To access
+these machines, you either need to boot with a liveCD and ssh in or
+hope that the sipb-xen maintainers add support for serial consoles.""",
+                        hvm_paravm="""
+HVM machines use the virtualization features of the processor, while
+ParaVM machines use Xen's emulation of virtualization features.  You
+want an HVM virtualized machine.""",
+                        cpu_weight="""
+Don't ask us!  We're as mystified as you are.""",
+                        owner="""
+The owner field is used to determine <a
+href="help?subject=quotas">quotas</a>.  It must be the name of a
+locker that you are an AFS administrator of.  In particular, you or an
+AFS group you are a member of must have AFS rlidwka bits on the
+locker.  You can check see who administers the LOCKER locker using the
+command 'fs la /mit/LOCKER' on Athena.)  See also <a
+href="help?subject=administrator">administrator</a>.""",
+                        administrator="""
+The administrator field determines who can access the console and
+power on and off the machine.  This can be either a user or a moira
+group.""",
+                        quotas="""
+Quotas are determined on a per-locker basis.  Each quota may have a
+maximum of 512 megabytes of active ram, 50 gigabytes of disk, and 4
+active machines."""
+                   )
+    
+    if not subjects:
+        subjects = sorted(help_mapping.keys())
+        

     d = dict(user=user,
     d = dict(user=user,

-             machine=machine)
-    print Template(file='info.tmpl',
-                   searchList=d)
+             simple=simple,
+             subjects=subjects,
+             mapping=help_mapping)
+    
+    return Template(file="help.tmpl", searchList=[d])
+    
+
+def badOperation(u, e):
+    raise CodeError("Unknown operation")
+
+def infoDict(user, machine):
+    status = controls.statusInfo(machine)
+    has_vnc = hasVnc(status)
+    if status is None:
+        main_status = dict(name=machine.name,
+                           memory=str(machine.memory))
+        uptime = None
+        cputime = None
+    else:
+        main_status = dict(status[1:])
+        start_time = float(main_status.get('start_time', 0))
+        uptime = datetime.timedelta(seconds=int(time.time()-start_time))
+        cpu_time_float = float(main_status.get('cpu_time', 0))
+        cputime = datetime.timedelta(seconds=int(cpu_time_float))
+    display_fields = """name uptime memory state cpu_weight on_reboot 
+     on_poweroff on_crash on_xend_start on_xend_stop bootloader""".split()
+    display_fields = [('name', 'Name'),
+                      ('owner', 'Owner'),
+                      ('administrator', 'Administrator'),
+                      ('contact', 'Contact'),
+                      ('type', 'Type'),
+                      'NIC_INFO',
+                      ('uptime', 'uptime'),
+                      ('cputime', 'CPU usage'),
+                      ('memory', 'RAM'),
+                      'DISK_INFO',
+                      ('state', 'state (xen format)'),
+                      ('cpu_weight', 'CPU weight'+helppopup('cpu_weight')),
+                      ('on_reboot', 'Action on VM reboot'),
+                      ('on_poweroff', 'Action on VM poweroff'),
+                      ('on_crash', 'Action on VM crash'),
+                      ('on_xend_start', 'Action on Xen start'),
+                      ('on_xend_stop', 'Action on Xen stop'),
+                      ('bootloader', 'Bootloader options'),
+                      ]
+    fields = []
+    machine_info = {}
+    machine_info['name'] = machine.name
+    machine_info['type'] = machine.type.hvm and 'HVM' or 'ParaVM'
+    machine_info['owner'] = machine.owner
+    machine_info['administrator'] = machine.administrator
+    machine_info['contact'] = machine.contact
+
+    nic_fields = getNicInfo(machine_info, machine)
+    nic_point = display_fields.index('NIC_INFO')
+    display_fields = (display_fields[:nic_point] + nic_fields + 
+                      display_fields[nic_point+1:])
+
+    disk_fields = getDiskInfo(machine_info, machine)
+    disk_point = display_fields.index('DISK_INFO')
+    display_fields = (display_fields[:disk_point] + disk_fields + 
+                      display_fields[disk_point+1:])
+    
+    main_status['memory'] += ' MiB'
+    for field, disp in display_fields:
+        if field in ('uptime', 'cputime') and locals()[field] is not None:
+            fields.append((disp, locals()[field]))
+        elif field in machine_info:
+            fields.append((disp, machine_info[field]))
+        elif field in main_status:
+            fields.append((disp, main_status[field]))
+        else:
+            pass
+            #fields.append((disp, None))
+    max_mem = validation.maxMemory(user, machine)
+    max_disk = validation.maxDisk(user, machine)
+    defaults = Defaults()
+    for name in 'machine_id name administrator owner memory contact'.split():
+        setattr(defaults, name, getattr(machine, name))
+    defaults.disk = "%0.2f" % (machine.disks[0].size/1024.)
+    d = dict(user=user,
+             cdroms=CDROM.select(),
+             on=status is not None,
+             machine=machine,
+             defaults=defaults,
+             has_vnc=has_vnc,
+             uptime=str(uptime),
+             ram=machine.memory,
+             max_mem=max_mem,
+             max_disk=max_disk,
+             owner_help=helppopup("owner"),
+             fields = fields)
+    return d
+
+def info(user, fields):
+    """Handler for info on a single VM."""
+    machine = validation.testMachineId(user, fields.getfirst('machine_id'))
+    d = infoDict(user, machine)
+    return Template(file='info.tmpl', searchList=[d])

 
 mapping = dict(list=listVms,
                vnc=vnc,
 
 mapping = dict(list=listVms,
                vnc=vnc,

+               command=command,
+               modify=modify,

                info=info,
                info=info,

-               create=create)
+               create=create,
+               help=helpHandler)
+
+def printHeaders(headers):
+    for key, value in headers.iteritems():
+        print '%s: %s' % (key, value)
+    print
+
+
+def getUser():
+    """Return the current user based on the SSL environment variables"""
+    if 'SSL_CLIENT_S_DN_Email' in os.environ:
+        username = os.environ['SSL_CLIENT_S_DN_Email'].split("@")[0]
+        return username
+    else:
+        return 'moo'
+
+def main(operation, user, fields):    
+    fun = mapping.get(operation, badOperation)
+
+    if fun not in (helpHandler, ):
+        connect('postgres://sipb-xen@sipb-xen-dev.mit.edu/sipb_xen')
+    try:
+        output = fun(u, fields)
+
+        headers = dict(DEFAULT_HEADERS)
+        if isinstance(output, tuple):
+            new_headers, output = output
+            headers.update(new_headers)
+
+        e = revertStandardError()
+        if e:
+            output.addError(e)
+        printHeaders(headers)
+        print output
+    except Exception, err:
+        if not fields.has_key('js'):
+            if isinstance(err, CodeError):
+                print 'Content-Type: text/html\n'
+                e = revertStandardError()
+                print error(operation, u, fields, err, e)
+                sys.exit(1)
+            if isinstance(err, InvalidInput):
+                print 'Content-Type: text/html\n'
+                e = revertStandardError()
+                print invalidInput(operation, u, fields, err, e)
+                sys.exit(1)
+        print 'Content-Type: text/plain\n'
+        print 'Uh-oh!  We experienced an error.'
+        print 'Please email sipb-xen@mit.edu with the contents of this page.'
+        print '----'
+        e = revertStandardError()
+        print e
+        print '----'
+        raise

 
 if __name__ == '__main__':
 
 if __name__ == '__main__':

+    start_time = time.time()

     fields = cgi.FieldStorage()
     fields = cgi.FieldStorage()

-    class C:
-        username = "moo"
-        email = 'moo@cow.com'
-    u = C()
-    connect('postgres://sipb-xen@sipb-xen-dev/sipb_xen')
+    u = getUser()
+    g.user = u

     operation = os.environ.get('PATH_INFO', '')
     operation = os.environ.get('PATH_INFO', '')

+    if not operation:
+        print "Status: 301 Moved Permanently"
+        print 'Location: ' + os.environ['SCRIPT_NAME']+'/\n'
+        sys.exit(0)
+

     if operation.startswith('/'):
         operation = operation[1:]
     if not operation:
         operation = 'list'
     if operation.startswith('/'):
         operation = operation[1:]
     if not operation:
         operation = 'list'

-    
-    fun = mapping.get(operation, 
-                      lambda u, e:
-                          error(operation, u, e,
-                                "Invalid operation '%'" % operation))
-    fun(u, fields)
+
+    main(operation, u, fields)
+