+###
+
"""Functionality common to all account classes.
-Each account class must provide five methods: create(), destroy(),
-configure(), start(), and stop(). In addition, it must provide static
-member variables SHELL, which contains the unique shell that it uses;
-and TYPE, which contains a description of the type that it uses. TYPE
-is divided hierarchically by periods; at the moment the only
-convention is that all sliver accounts have type that begins with
-sliver.
+Each subclass of Account must provide five methods:
+ (*) create() and destroy(), which are static;
+ (*) configure(), start(), and stop(), which are not.
-Because Python does dynamic method lookup, we do not bother with a
-boilerplate abstract superclass.
+configure(), which takes a record as its only argument, does
+things like set up ssh keys. In addition, an Account subclass must
+provide static member variables SHELL, which contains the unique shell
+that it uses; and TYPE, a string that is used by the account creation
+code. For no particular reason, TYPE is divided hierarchically by
+periods; at the moment the only convention is that all sliver accounts
+have type that begins with sliver.
There are any number of race conditions that may result from the fact
that account names are not unique over time. Moreover, it's a bad
maximum stack size.
"""
-import Queue
import os
-import pwd
+import pwd, grp
import threading
import logger
# account type -> account class association
type_acct_class = {}
+# these semaphores are acquired before creating/destroying an account
+create_sem = threading.Semaphore(1)
+destroy_sem = threading.Semaphore(1)
+
def register_class(acct_class):
- """Call once for each account class. This method adds the class to the dictionaries used to look up account classes by shell and type."""
+ """Call once for each account class. This method adds the class
+to the dictionaries used to look up account classes by shell and
+type."""
shell_acct_class[acct_class.SHELL] = acct_class
type_acct_class[acct_class.TYPE] = acct_class
# private account name -> worker object association and associated lock
-_name_worker_lock = threading.Lock()
-_name_worker = {}
+name_worker_lock = threading.Lock()
+name_worker = {}
+
+def allpwents():
+ return [pw_ent for pw_ent in pwd.getpwall() if pw_ent[6] in shell_acct_class]
def all():
"""Return the names of all accounts on the system with recognized shells."""
- return [pw_ent[0] for pw_ent in pwd.getpwall() if pw_ent[6] in shell_acct_class]
+ return [pw_ent[0] for pw_ent in allpwents()]
def get(name):
"""Return the worker object for a particular username. If no such object exists, create it first."""
- _name_worker_lock.acquire()
+ name_worker_lock.acquire()
try:
- if name not in _name_worker: _name_worker[name] = Worker(name)
- return _name_worker[name]
- finally: _name_worker_lock.release()
-
-
-def install_keys(rec):
- """Write <rec['keys']> to <rec['name']>'s authorized_keys file."""
- name = rec['name']
- dot_ssh = '/home/%s/.ssh' % name
- def do_installation():
- if not os.access(dot_ssh, os.F_OK): os.mkdir(dot_ssh)
- tools.write_file(dot_ssh + '/authorized_keys', lambda thefile: thefile.write(rec['keys']))
- logger.log('%s: installing ssh keys' % name)
- tools.fork_as(name, do_installation)
-
+ if name not in name_worker: name_worker[name] = Worker(name)
+ return name_worker[name]
+ finally: name_worker_lock.release()
+
+
+class Account:
+ def __init__(self, rec):
+ logger.verbose('accounts: Initing account %s'%rec['name'])
+ self.name = rec['name']
+ self.keys = ''
+ self.configure(rec)
+
+ @staticmethod
+ def create(name, vref = None): abstract
+
+ @staticmethod
+ def destroy(name): abstract
+
+ def configure(self, rec):
+ """Write <rec['keys']> to my authorized_keys file."""
+ logger.verbose('accounts: configuring %s'%self.name)
+ new_keys = rec['keys']
+ if new_keys != self.keys:
+ # get the unix account info
+ gid = grp.getgrnam("slices")[2]
+ pw_info = pwd.getpwnam(self.name)
+ uid = pw_info[2]
+ pw_dir = pw_info[5]
+
+ # write out authorized_keys file and conditionally create
+ # the .ssh subdir if need be.
+ dot_ssh = os.path.join(pw_dir,'.ssh')
+ if not os.path.isdir(dot_ssh):
+ if not os.path.isdir(pw_dir):
+ logger.verbose('accounts: WARNING: homedir %s does not exist for %s!'%(pw_dir,self.name))
+ os.mkdir(pw_dir)
+ os.chown(pw_dir, uid, gid)
+ os.mkdir(dot_ssh)
+
+ auth_keys = os.path.join(dot_ssh,'authorized_keys')
+ tools.write_file(auth_keys, lambda f: f.write(new_keys))
+
+ # set access permissions and ownership properly
+ os.chmod(dot_ssh, 0700)
+ os.chown(dot_ssh, uid, gid)
+ os.chmod(auth_keys, 0600)
+ os.chown(auth_keys, uid, gid)
+
+ # set self.keys to new_keys only when all of the above ops succeed
+ self.keys = new_keys
+
+ logger.log('accounts: %s: installed ssh keys' % self.name)
+
+ def start(self, delay=0): pass
+ def stop(self): pass
+ def is_running(self): pass
class Worker:
- # these semaphores are acquired before creating/destroying an account
- _create_sem = threading.Semaphore(1)
- _destroy_sem = threading.Semaphore(1)
def __init__(self, name):
self.name = name # username
self._acct = None # the account object currently associated with this worker
- # task list
- # outsiders request operations by putting (fn, args...) tuples on _q
- # the worker thread (created below) will perform these operations in order
- self._q = Queue.Queue()
- tools.as_daemon_thread(self._run)
def ensure_created(self, rec):
- """Cause the account specified by <rec> to exist if it doesn't already."""
- self._q.put((self._ensure_created, rec.copy()))
-
- def _ensure_created(self, rec):
+ """Check account type is still valid. If not, recreate sliver.
+If still valid, check if running and configure/start if not."""
+ logger.log_data_in_file(rec,"/var/lib/nodemanager/%s.rec.txt"%rec['name'],
+ 'raw rec captured in ensure_created',logger.LOG_VERBOSE)
curr_class = self._get_class()
- next_class = type_acct_class[rec['account_type']]
+ next_class = type_acct_class[rec['type']]
if next_class != curr_class:
self._destroy(curr_class)
- self._create_sem.acquire()
- try: next_class.create(self.name)
- finally: self._create_sem.release()
- self._make_acct_obj()
+ create_sem.acquire()
+ try: next_class.create(self.name, rec)
+ finally: create_sem.release()
+ if not isinstance(self._acct, next_class): self._acct = next_class(rec)
+ logger.verbose("accounts.ensure_created: %s, running=%r"%(self.name,self.is_running()))
+
+ # reservation_alive is set on reervable nodes, and its value is a boolean
+ if 'reservation_alive' in rec:
+ # reservable nodes
+ if rec['reservation_alive']:
+ # this sliver has the lease, it is safe to start it
+ if not self.is_running(): self.start(rec)
+ else: self.configure(rec)
+ else:
+ # not having the lease, do not start it
+ self.configure(rec)
+ # usual nodes - preserve old code
+ # xxx it's not clear what to do when a sliver changes type/class
+ # in a reservable node
+ else:
+ if not self.is_running() or next_class != curr_class:
+ self.start(rec)
+ else: self.configure(rec)
+
+ def ensure_destroyed(self): self._destroy(self._get_class())
+
+ def start(self, rec, d = 0):
self._acct.configure(rec)
- if next_class != curr_class: self._acct.start()
+ self._acct.start(delay=d)
- def ensure_destroyed(self): self._q.put((self._ensure_destroyed,))
- def _ensure_destroyed(self): self._destroy(self._get_class())
+ def configure(self, rec):
+ self._acct.configure(rec)
- def start(self): self._q.put((self._start,))
- def _start(self):
- self._make_acct_obj()
- self._acct.start()
+ def stop(self): self._acct.stop()
- def stop(self): self._q.put((self._stop,))
- def _stop(self):
- self._make_acct_obj()
- self._acct.stop()
+ def is_running(self):
+ if (self._acct != None) and self._acct.is_running():
+ status = True
+ else:
+ status = False
+ logger.verbose("accounts: Worker(%s): is not running" % self.name)
+ return status
def _destroy(self, curr_class):
self._acct = None
if curr_class:
- self._destroy_sem.acquire()
+ destroy_sem.acquire()
try: curr_class.destroy(self.name)
- finally: self._destroy_sem.release()
+ finally: destroy_sem.release()
def _get_class(self):
try: shell = pwd.getpwnam(self.name)[6]
except KeyError: return None
return shell_acct_class[shell]
-
- def _make_acct_obj(self):
- curr_class = self._get_class()
- if not isinstance(self._acct, curr_class): self._acct = curr_class(self.name)
-
- def _run(self):
- while True:
- try:
- cmd = self._q.get()
- cmd[0](*cmd[1:])
- except: logger.log_exc()
git://git.onelab.eu / nodemanager.git / blobdiff