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Revision ea03467c

     """Module implementing the job queue handling.
     Locking:
     There's a single, large lock in the JobQueue class. It's used by all other
     classes in this module.
     Locking: there's a single, large lock in the L{JobQueue} class. It's
     used by all other classes in this module.
     @var JOBQUEUE_THREADS: the number of worker threads we start for
         processing jobs
     """
-...
     def TimeStampNow():
       """Returns the current timestamp.
       @rtype: tuple
       @return: the current time in the (seconds, microseconds) format
       """
       return utils.SplitTime(time.time())
     class _QueuedOpCode(object):
       """Encasulates an opcode object.
       The 'log' attribute holds the execution log and consists of tuples
       of the form (log_serial, timestamp, level, message).
       @ivar log: holds the execution log and consists of tuples
       of the form C{(log_serial, timestamp, level, message)}
       @ivar input: the OpCode we encapsulate
       @ivar status: the current status
       @ivar result: the result of the LU execution
       @ivar start_timestamp: timestamp for the start of the execution
       @ivar stop_timestamp: timestamp for the end of the execution
       """
       def __init__(self, op):
         """Constructor for the _QuededOpCode.
         @type op: L{opcodes.OpCode}
         @param op: the opcode we encapsulate
         """
         self.input = op
         self.status = constants.OP_STATUS_QUEUED
         self.result = None
-...
       @classmethod
       def Restore(cls, state):
         """Restore the _QueuedOpCode from the serialized form.
         @type state: dict
         @param state: the serialized state
         @rtype: _QueuedOpCode
         @return: a new _QueuedOpCode instance
         """
         obj = _QueuedOpCode.__new__(cls)
         obj.input = opcodes.OpCode.LoadOpCode(state["input"])
         obj.status = state["status"]
-...
         return obj
       def Serialize(self):
         """Serializes this _QueuedOpCode.
         @rtype: dict
         @return: the dictionary holding the serialized state
         """
         return {
           "input": self.input.__getstate__(),
           "status": self.status,
-...
     class _QueuedJob(object):
       """In-memory job representation.
       This is what we use to track the user-submitted jobs. Locking must be taken
       care of by users of this class.
       This is what we use to track the user-submitted jobs. Locking must
       be taken care of by users of this class.
       @type queue: L{JobQueue}
       @ivar queue: the parent queue
       @ivar id: the job ID
       @type ops: list
       @ivar ops: the list of _QueuedOpCode that constitute the job
       @type run_op_index: int
       @ivar run_op_index: the currently executing opcode, or -1 if
           we didn't yet start executing
       @type log_serial: int
       @ivar log_serial: holds the index for the next log entry
       @ivar received_timestamp: the timestamp for when the job was received
       @ivar start_timestmap: the timestamp for start of execution
       @ivar end_timestamp: the timestamp for end of execution
       @ivar change: a Condition variable we use for waiting for job changes
       """
       def __init__(self, queue, job_id, ops):
         """Constructor for the _QueuedJob.
         @type queue: L{JobQueue}
         @param queue: our parent queue
         @type job_id: job_id
         @param job_id: our job id
         @type ops: list
         @param ops: the list of opcodes we hold, which will be encapsulated
             in _QueuedOpCodes
         """
         if not ops:
           # TODO
           # TODO: use a better exception
           raise Exception("No opcodes")
         self.queue = queue
-...
       @classmethod
       def Restore(cls, queue, state):
         """Restore a _QueuedJob from serialized state:
         @type queue: L{JobQueue}
         @param queue: to which queue the restored job belongs
         @type state: dict
         @param state: the serialized state
         @rtype: _JobQueue
         @return: the restored _JobQueue instance
         """
         obj = _QueuedJob.__new__(cls)
         obj.queue = queue
         obj.id = state["id"]
-...
         return obj
       def Serialize(self):
         """Serialize the _JobQueue instance.
         @rtype: dict
         @return: the serialized state
         """
         return {
           "id": self.id,
           "ops": [op.Serialize() for op in self.ops],
-...
+          }
       def CalcStatus(self):
         """Compute the status of this job.
         This function iterates over all the _QueuedOpCodes in the job and
         based on their status, computes the job status.
         The algorithm is:
           - if we find a cancelled, or finished with error, the job
             status will be the same
           - otherwise, the last opcode with the status one of:
               - waitlock
               - running
             will determine the job status
           - otherwise, it means either all opcodes are queued, or success,
             and the job status will be the same
         @return: the job status
         """
         status = constants.JOB_STATUS_QUEUED
         all_success = True
-...
         return status
       def GetLogEntries(self, newer_than):
         """Selectively returns the log entries.
         @type newer_than: None or int
         @param newer_than: if this is None, return all log enties,
             otherwise return only the log entries with serial higher
             than this value
         @rtype: list
         @return: the list of the log entries selected
         """
         if newer_than is None:
           serial = -1
         else:
-...
     class _JobQueueWorker(workerpool.BaseWorker):
       """The actual job workers.
       """
       def _NotifyStart(self):
         """Mark the opcode as running, not lock-waiting.
-...
         This functions processes a job. It is closely tied to the _QueuedJob and
         _QueuedOpCode classes.
         @type job: L{_QueuedJob}
         @param job: the job to be processed
         """
         logging.debug("Worker %s processing job %s",
                       self.worker_id, job.id)
-...
     class _JobQueueWorkerPool(workerpool.WorkerPool):
       """Simple class implementing a job-processing workerpool.
       """
       def __init__(self, queue):
         super(_JobQueueWorkerPool, self).__init__(JOBQUEUE_THREADS,
                                                   _JobQueueWorker)
-...
     class JobQueue(object):
       """Quue used to manaage the jobs.
       @cvar _RE_JOB_FILE: regex matching the valid job file names
       """
       _RE_JOB_FILE = re.compile(r"^job-(%s)$" % constants.JOB_ID_TEMPLATE)
       def _RequireOpenQueue(fn):
         """Decorator for "public" functions.
         This function should be used for all "public" functions. That is, functions
         usually called from other classes.
         This function should be used for all 'public' functions. That is,
         functions usually called from other classes.
         Important: Use this decorator only after utils.LockedMethod!
         @warning: Use this decorator only after utils.LockedMethod!
         Example:
         Example::
           @utils.LockedMethod
           @_RequireOpenQueue
           def Example(self):
-...
         return wrapper
       def __init__(self, context):
         """Constructor for JobQueue.
         The constructor will initialize the job queue object and then
         start loading the current jobs from disk, either for starting them
         (if they were queue) or for aborting them (if they were already
         running).
         @type context: GanetiContext
         @param context: the context object for access to the configuration
             data and other ganeti objects
         """
         self.context = context
         self._memcache = weakref.WeakValueDictionary()
         self._my_hostname = utils.HostInfo().name
-...
       @utils.LockedMethod
       @_RequireOpenQueue
       def RemoveNode(self, node_name):
         """Callback called when removing nodes from the cluster.
         @type node_name: str
         @param node_name: the name of the node to remove
         """
         try:
           # The queue is removed by the "leave node" RPC call.
           del self._nodes[node_name]
-...
           pass
       def _CheckRpcResult(self, result, nodes, failmsg):
         """Verifies the status of an RPC call.
         Since we aim to keep consistency should this node (the current
         master) fail, we will log errors if our rpc fail, and especially
         log the case when more than half of the nodes failes.
         @param result: the data as returned from the rpc call
         @type nodes: list
         @param nodes: the list of nodes we made the call to
         @type failmsg: str
         @param failmsg: the identifier to be used for logging
         """
         failed = []
         success = []
-...
       def _GetNodeIp(self):
         """Helper for returning the node name/ip list.
         @rtype: (list, list)
         @return: a tuple of two lists, the first one with the node
             names and the second one with the node addresses
         """
         name_list = self._nodes.keys()
         addr_list = [self._nodes[name] for name in name_list]
-...
       def _WriteAndReplicateFileUnlocked(self, file_name, data):
         """Writes a file locally and then replicates it to all nodes.
         This function will replace the contents of a file on the local
         node and then replicate it to all the other nodes we have.
         @type file_name: str
         @param file_name: the path of the file to be replicated
         @type data: str
         @param data: the new contents of the file
         """
         utils.WriteFile(file_name, data=data)
-...
                              "Updating %s" % file_name)
       def _RenameFileUnlocked(self, old, new):
         """Renames a file locally and then replicate the change.
         This function will rename a file in the local queue directory
         and then replicate this rename to all the other nodes we have.
         @type old: str
         @param old: the current name of the file
         @type new: str
         @param new: the new name of the file
         """
         os.rename(old, new)
         names, addrs = self._GetNodeIp()
-...
                              "Moving %s to %s" % (old, new))
       def _FormatJobID(self, job_id):
         """Convert a job ID to string format.
         Currently this just does C{str(job_id)} after performing some
         checks, but if we want to change the job id format this will
         abstract this change.
         @type job_id: int or long
         @param job_id: the numeric job id
         @rtype: str
         @return: the formatted job id
         """
         if not isinstance(job_id, (int, long)):
           raise errors.ProgrammerError("Job ID '%s' not numeric" % job_id)
         if job_id < 0:
-...
         Job identifiers are unique during the lifetime of a cluster.
         Returns: A string representing the job identifier.
         @rtype: str
         @return: a string representing the job identifier.
         """
         # New number
-...
       @staticmethod
       def _GetJobPath(job_id):
         """Returns the job file for a given job id.
         @type job_id: str
         @param job_id: the job identifier
         @rtype: str
         @return: the path to the job file
         """
         return os.path.join(constants.QUEUE_DIR, "job-%s" % job_id)
       @staticmethod
       def _GetArchivedJobPath(job_id):
         """Returns the archived job file for a give job id.
         @type job_id: str
         @param job_id: the job identifier
         @rtype: str
         @return: the path to the archived job file
         """
         return os.path.join(constants.JOB_QUEUE_ARCHIVE_DIR, "job-%s" % job_id)
       @classmethod
       def _ExtractJobID(cls, name):
         """Extract the job id from a filename.
         @type name: str
         @param name: the job filename
         @rtype: job id or None
         @return: the job id corresponding to the given filename,
             or None if the filename does not represent a valid
             job file
         """
         m = cls._RE_JOB_FILE.match(name)
         if m:
           return m.group(1)
-...
         jobs are present on disk (so in the _memcache we don't have any
         extra IDs).
         @rtype: list
         @return: the list of job IDs
         """
         jlist = [self._ExtractJobID(name) for name in self._ListJobFiles()]
         jlist = utils.NiceSort(jlist)
         return jlist
       def _ListJobFiles(self):
         """Returns the list of current job files.
         @rtype: list
         @return: the list of job file names
         """
         return [name for name in utils.ListVisibleFiles(constants.QUEUE_DIR)
                 if self._RE_JOB_FILE.match(name)]
       def _LoadJobUnlocked(self, job_id):
         """Loads a job from the disk or memory.
         Given a job id, this will return the cached job object if
         existing, or try to load the job from the disk. If loading from
         disk, it will also add the job to the cache.
         @param job_id: the job id
         @rtype: L{_QueuedJob} or None
         @return: either None or the job object
         """
         job = self._memcache.get(job_id, None)
         if job:
           logging.debug("Found job %s in memcache", job_id)
-...
         return job
       def _GetJobsUnlocked(self, job_ids):
         """Return a list of jobs based on their IDs.
         @type job_ids: list
         @param job_ids: either an empty list (meaning all jobs),
             or a list of job IDs
         @rtype: list
         @return: the list of job objects
         """
         if not job_ids:
           job_ids = self._GetJobIDsUnlocked()
-...
         This currently uses the queue drain file, which makes it a
         per-node flag. In the future this can be moved to the config file.
         @rtype: boolean
         @return: True of the job queue is marked for draining
         """
         return os.path.exists(constants.JOB_QUEUE_DRAIN_FILE)
-...
         This is similar to the function L{backend.JobQueueSetDrainFlag},
         and in the future we might merge them.
         @type drain_flag: boolean
         @param drain_flag: wheter to set or unset the drain flag
         """
         if drain_flag:
           utils.WriteFile(constants.JOB_QUEUE_DRAIN_FILE, data="", close=True)
-...
         @type ops: list
         @param ops: The list of OpCodes that will become the new job.
         @rtype: job ID
         @return: the job ID of the newly created job
         @raise errors.JobQueueDrainError: if the job is marked for draining
         """
         if self._IsQueueMarkedDrain():
-...
       @_RequireOpenQueue
       def UpdateJobUnlocked(self, job):
         """Update a job's on disk storage.
         After a job has been modified, this function needs to be called in
         order to write the changes to disk and replicate them to the other
         nodes.
         @type job: L{_QueuedJob}
         @param job: the changed job
         """
         filename = self._GetJobPath(job.id)
         data = serializer.DumpJson(job.Serialize(), indent=False)
         logging.debug("Writing job %s to %s", job.id, filename)
-...
         @param prev_log_serial: Last job message serial number
         @type timeout: float
         @param timeout: maximum time to wait
         @rtype: tuple (job info, log entries)
         @return: a tuple of the job information as required via
             the fields parameter, and the log entries as a list
             if the job has not changed and the timeout has expired,
             we instead return a special value,
             L{constants.JOB_NOTCHANGED}, which should be interpreted
             as such by the clients
         """
         logging.debug("Waiting for changes in job %s", job_id)
-...
       def CancelJob(self, job_id):
         """Cancels a job.
         This will only succeed if the job has not started yet.
         @type job_id: string
         @param job_id: Job ID of job to be cancelled.
         @param job_id: job ID of job to be cancelled.
         """
         logging.debug("Cancelling job %s", job_id)
-...
       def ArchiveJob(self, job_id):
         """Archives a job.
         This is just a wrapper over L{_ArchiveJobUnlocked}.
         @type job_id: string
         @param job_id: Job ID of job to be archived.
-...
             self._ArchiveJobUnlocked(jid)
       def _GetJobInfoUnlocked(self, job, fields):
         """Returns information about a job.
         @type job: L{_QueuedJob}
         @param job: the job which we query
         @type fields: list
         @param fields: names of fields to return
         @rtype: list
         @return: list with one element for each field
         @raise errors.OpExecError: when an invalid field
             has been passed
         """
         row = []
         for fname in fields:
           if fname == "id":
-...
       def QueryJobs(self, job_ids, fields):
         """Returns a list of jobs in queue.
         Args:
         - job_ids: Sequence of job identifiers or None for all
         - fields: Names of fields to return
         This is a wrapper of L{_GetJobsUnlocked}, which actually does the
         processing for each job.
         @type job_ids: list
         @param job_ids: sequence of job identifiers or None for all
         @type fields: list
         @param fields: names of fields to return
         @rtype: list
         @return: list one element per job, each element being list with
             the requested fields
         """
         jobs = []
-...
       def Shutdown(self):
         """Stops the job queue.
         This shutdowns all the worker threads an closes the queue.
         """
         self._wpool.TerminateWorkers()

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Synnefo » snf-ganeti

Revision ea03467c