Initial Commit

lib/apscheduler/job.py

@@ -0,0 +1,252 @@
+from collections import Iterable, Mapping
+from uuid import uuid4
+
+import six
+
+from apscheduler.triggers.base import BaseTrigger
+from apscheduler.util import ref_to_obj, obj_to_ref, datetime_repr, repr_escape, get_callable_name, check_callable_args, \
+    convert_to_datetime
+
+
+class Job(object):
+    """
+    Contains the options given when scheduling callables and its current schedule and other state.
+    This class should never be instantiated by the user.
+
+    :var str id: the unique identifier of this job
+    :var str name: the description of this job
+    :var func: the callable to execute
+    :var tuple|list args: positional arguments to the callable
+    :var dict kwargs: keyword arguments to the callable
+    :var bool coalesce: whether to only run the job once when several run times are due
+    :var trigger: the trigger object that controls the schedule of this job
+    :var str executor: the name of the executor that will run this job
+    :var int misfire_grace_time: the time (in seconds) how much this job's execution is allowed to be late
+    :var int max_instances: the maximum number of concurrently executing instances allowed for this job
+    :var datetime.datetime next_run_time: the next scheduled run time of this job
+    """
+
+    __slots__ = ('_scheduler', '_jobstore_alias', 'id', 'trigger', 'executor', 'func', 'func_ref', 'args', 'kwargs',
+                 'name', 'misfire_grace_time', 'coalesce', 'max_instances', 'next_run_time')
+
+    def __init__(self, scheduler, id=None, **kwargs):
+        super(Job, self).__init__()
+        self._scheduler = scheduler
+        self._jobstore_alias = None
+        self._modify(id=id or uuid4().hex, **kwargs)
+
+    def modify(self, **changes):
+        """
+        Makes the given changes to this job and saves it in the associated job store.
+        Accepted keyword arguments are the same as the variables on this class.
+
+        .. seealso:: :meth:`~apscheduler.schedulers.base.BaseScheduler.modify_job`
+        """
+
+        self._scheduler.modify_job(self.id, self._jobstore_alias, **changes)
+
+    def reschedule(self, trigger, **trigger_args):
+        """
+        Shortcut for switching the trigger on this job.
+
+        .. seealso:: :meth:`~apscheduler.schedulers.base.BaseScheduler.reschedule_job`
+        """
+
+        self._scheduler.reschedule_job(self.id, self._jobstore_alias, trigger, **trigger_args)
+
+    def pause(self):
+        """
+        Temporarily suspend the execution of this job.
+
+        .. seealso:: :meth:`~apscheduler.schedulers.base.BaseScheduler.pause_job`
+        """
+
+        self._scheduler.pause_job(self.id, self._jobstore_alias)
+
+    def resume(self):
+        """
+        Resume the schedule of this job if previously paused.
+
+        .. seealso:: :meth:`~apscheduler.schedulers.base.BaseScheduler.resume_job`
+        """
+
+        self._scheduler.resume_job(self.id, self._jobstore_alias)
+
+    def remove(self):
+        """
+        Unschedules this job and removes it from its associated job store.
+
+        .. seealso:: :meth:`~apscheduler.schedulers.base.BaseScheduler.remove_job`
+        """
+
+        self._scheduler.remove_job(self.id, self._jobstore_alias)
+
+    @property
+    def pending(self):
+        """Returns ``True`` if the referenced job is still waiting to be added to its designated job store."""
+
+        return self._jobstore_alias is None
+
+    #
+    # Private API
+    #
+
+    def _get_run_times(self, now):
+        """
+        Computes the scheduled run times between ``next_run_time`` and ``now`` (inclusive).
+
+        :type now: datetime.datetime
+        :rtype: list[datetime.datetime]
+        """
+
+        run_times = []
+        next_run_time = self.next_run_time
+        while next_run_time and next_run_time <= now:
+            run_times.append(next_run_time)
+            next_run_time = self.trigger.get_next_fire_time(next_run_time, now)
+
+        return run_times
+
+    def _modify(self, **changes):
+        """Validates the changes to the Job and makes the modifications if and only if all of them validate."""
+
+        approved = {}
+
+        if 'id' in changes:
+            value = changes.pop('id')
+            if not isinstance(value, six.string_types):
+                raise TypeError("id must be a nonempty string")
+            if hasattr(self, 'id'):
+                raise ValueError('The job ID may not be changed')
+            approved['id'] = value
+
+        if 'func' in changes or 'args' in changes or 'kwargs' in changes:
+            func = changes.pop('func') if 'func' in changes else self.func
+            args = changes.pop('args') if 'args' in changes else self.args
+            kwargs = changes.pop('kwargs') if 'kwargs' in changes else self.kwargs
+
+            if isinstance(func, str):
+                func_ref = func
+                func = ref_to_obj(func)
+            elif callable(func):
+                try:
+                    func_ref = obj_to_ref(func)
+                except ValueError:
+                    # If this happens, this Job won't be serializable
+                    func_ref = None
+            else:
+                raise TypeError('func must be a callable or a textual reference to one')
+
+            if not hasattr(self, 'name') and changes.get('name', None) is None:
+                changes['name'] = get_callable_name(func)
+
+            if isinstance(args, six.string_types) or not isinstance(args, Iterable):
+                raise TypeError('args must be a non-string iterable')
+            if isinstance(kwargs, six.string_types) or not isinstance(kwargs, Mapping):
+                raise TypeError('kwargs must be a dict-like object')
+
+            check_callable_args(func, args, kwargs)
+
+            approved['func'] = func
+            approved['func_ref'] = func_ref
+            approved['args'] = args
+            approved['kwargs'] = kwargs
+
+        if 'name' in changes:
+            value = changes.pop('name')
+            if not value or not isinstance(value, six.string_types):
+                raise TypeError("name must be a nonempty string")
+            approved['name'] = value
+
+        if 'misfire_grace_time' in changes:
+            value = changes.pop('misfire_grace_time')
+            if value is not None and (not isinstance(value, six.integer_types) or value <= 0):
+                raise TypeError('misfire_grace_time must be either None or a positive integer')
+            approved['misfire_grace_time'] = value
+
+        if 'coalesce' in changes:
+            value = bool(changes.pop('coalesce'))
+            approved['coalesce'] = value
+
+        if 'max_instances' in changes:
+            value = changes.pop('max_instances')
+            if not isinstance(value, six.integer_types) or value <= 0:
+                raise TypeError('max_instances must be a positive integer')
+            approved['max_instances'] = value
+
+        if 'trigger' in changes:
+            trigger = changes.pop('trigger')
+            if not isinstance(trigger, BaseTrigger):
+                raise TypeError('Expected a trigger instance, got %s instead' % trigger.__class__.__name__)
+
+            approved['trigger'] = trigger
+
+        if 'executor' in changes:
+            value = changes.pop('executor')
+            if not isinstance(value, six.string_types):
+                raise TypeError('executor must be a string')
+            approved['executor'] = value
+
+        if 'next_run_time' in changes:
+            value = changes.pop('next_run_time')
+            approved['next_run_time'] = convert_to_datetime(value, self._scheduler.timezone, 'next_run_time')
+
+        if changes:
+            raise AttributeError('The following are not modifiable attributes of Job: %s' % ', '.join(changes))
+
+        for key, value in six.iteritems(approved):
+            setattr(self, key, value)
+
+    def __getstate__(self):
+        # Don't allow this Job to be serialized if the function reference could not be determined
+        if not self.func_ref:
+            raise ValueError('This Job cannot be serialized since the reference to its callable (%r) could not be '
+                             'determined. Consider giving a textual reference (module:function name) instead.' %
+                             (self.func,))
+
+        return {
+            'version': 1,
+            'id': self.id,
+            'func': self.func_ref,
+            'trigger': self.trigger,
+            'executor': self.executor,
+            'args': self.args,
+            'kwargs': self.kwargs,
+            'name': self.name,
+            'misfire_grace_time': self.misfire_grace_time,
+            'coalesce': self.coalesce,
+            'max_instances': self.max_instances,
+            'next_run_time': self.next_run_time
+        }
+
+    def __setstate__(self, state):
+        if state.get('version', 1) > 1:
+            raise ValueError('Job has version %s, but only version 1 can be handled' % state['version'])
+
+        self.id = state['id']
+        self.func_ref = state['func']
+        self.func = ref_to_obj(self.func_ref)
+        self.trigger = state['trigger']
+        self.executor = state['executor']
+        self.args = state['args']
+        self.kwargs = state['kwargs']
+        self.name = state['name']
+        self.misfire_grace_time = state['misfire_grace_time']
+        self.coalesce = state['coalesce']
+        self.max_instances = state['max_instances']
+        self.next_run_time = state['next_run_time']
+
+    def __eq__(self, other):
+        if isinstance(other, Job):
+            return self.id == other.id
+        return NotImplemented
+
+    def __repr__(self):
+        return '<Job (id=%s name=%s)>' % (repr_escape(self.id), repr_escape(self.name))
+
+    def __str__(self):
+        return '%s (trigger: %s, next run at: %s)' % (repr_escape(self.name), repr_escape(str(self.trigger)),
+                                                      datetime_repr(self.next_run_time))
+
+    def __unicode__(self):
+        return six.u('%s (trigger: %s, next run at: %s)') % (self.name, self.trigger, datetime_repr(self.next_run_time))