class IndexedOrderedStore(Store):
"""Resource with *capacity* slots for storing objects in order and
retrieving multiple items simultaneously from arbitrary positions in the
:class:`IndexedOrderedStore`. All items in an *IndexedOrderedStore*
instance must be orderable, which is to say that items must implement
:meth:`~object.__lt__()`.
"""
put = BoundClass(StorePut)
"""Request to put an *item* into the store."""
get = BoundClass(IndexedOrderedStoreGet)
"""Request to get *items* at *indices* out of the store."""
def _do_put(self, event):
if len(self.items) < self._capacity:
insort(self.items, event.item)
event.succeed()
def _do_get(self, event):
if len(event.indices) == 1:
event.succeed([self.items.pop(event.indices[0])])
return
result = []
for idx, val in enumerate(event.indices):
result.append(self.items[val])
self.items[val] = self.items[-1 - idx]
if len(event.indices) > 0:
del self.items[-len(event.indices):]
self.items.sort()
event.succeed(result)
class FilterStore(Store):
"""Resource with *capacity* slots for storing arbitrary objects supporting
filtered get requests. Like the :class:`Store`, the *capacity* is unlimited
by default and objects are put and retrieved from the store in a first-in
first-out order.
Get requests can be customized with a filter function to only trigger for
items for which said filter function returns ``True``.
.. note::
In contrast to :class:`Store`, get requests of a :class:`FilterStore`
won't necessarily be triggered in the same order they were issued.
*Example:* The store is empty. *Process 1* tries to get an item of type
*a*, *Process 2* an item of type *b*. Another process puts one item of
type *b* into the store. Though *Process 2* made his request after
*Process 1*, it will receive that new item because *Process 1* doesn't
want it.
"""
put = BoundClass(StorePut)
"""Request a to put *item* into the store."""
get = BoundClass(FilterStoreGet)
"""Request a to get an *item*, for which *filter* returns ``True``, out of
the store."""
def _do_get(self, event):
for item in self.items:
if event.filter(item):
self.items.remove(item)
event.succeed(item)
break
return True
class Store(base.BaseResource):
"""Resource with *capacity* slots for storing arbitrary objects. By
default, the *capacity* is unlimited and objects are put and retrieved from
the store in a first-in first-out order.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
"""
def __init__(self, env, capacity=float('inf')):
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
super(Store, self).__init__(env, capacity)
self.items = []
"""List of the items available in the store."""
put = BoundClass(StorePut)
"""Request to put *item* into the store."""
get = BoundClass(StoreGet)
"""Request to get an *item* out of the store."""
def _do_put(self, event):
if len(self.items) < self._capacity:
self.items.append(event.item)
event.succeed()
def _do_get(self, event):
if self.items:
event.succeed(self.items.pop(0))
class Resource(base.BaseResource):
"""Resource with *capacity* of usage slots that can be requested by
processes.
If all slots are taken, requests are enqueued. Once a usage request is
released, a pending request will be triggered.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
resource is bound to.
"""
def __init__(self, env: Environment, capacity: int = 1):
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
super().__init__(env, capacity)
self.users: List[Request] = []
"""List of :class:`Request` events for the processes that are currently
using the resource."""
self.queue = self.put_queue
"""Queue of pending :class:`Request` events. Alias of
:attr:`~simpy.resources.base.BaseResource.put_queue`.
"""
@property
def count(self) -> int:
"""Number of users currently using the resource."""
return len(self.users)
if TYPE_CHECKING:
def request(self) -> Request:
"""Request a usage slot."""
return Request(self)
def release(self, request: Request) -> Release:
"""Release a usage slot."""
return Release(self, request)
else:
request = BoundClass(Request)
release = BoundClass(Release)
def _do_put(self, event: Request) -> None:
if len(self.users) < self.capacity:
self.users.append(event)
event.usage_since = self._env.now
event.succeed()
def _do_get(self, event: Release) -> None:
try:
self.users.remove(event.request) # type: ignore
except ValueError:
pass
event.succeed()
class Container(base.BaseResource):
"""Models the production and consumption of a homogeneous, undifferentiated
bulk. It may either be continuous (like water) or discrete (like apples).
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
The *capacity* defines the size of the container and must be a positive
number (> 0). By default, a container is of unlimited size. You can
specify the initial level of the container via *init*. It must be >=
0 and is 0 by default.
Raise a :exc:`ValueError` if ``capacity <= 0``, ``init < 0`` or
``init > capacity``.
"""
def __init__(self, env, capacity=float('inf'), init=0):
super(Container, self).__init__(env)
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
if init < 0:
raise ValueError('"init" must be >= 0.')
if init > capacity:
raise ValueError('"init" must be <= "capacity".')
self._capacity = capacity
self._level = init
@property
def capacity(self):
"""The maximum capacity of the container."""
return self._capacity
@property
def level(self):
"""The current level of the container (a number between ``0`` and
``capacity``).
"""
return self._level
put = BoundClass(ContainerPut)
"""Creates a new :class:`ContainerPut` event."""
get = BoundClass(ContainerGet)
"""Creates a new :class:`ContainerGet` event."""
def _do_put(self, event):
if self._capacity - self._level >= event.amount:
self._level += event.amount
event.succeed()
def _do_get(self, event):
if self._level >= event.amount:
self._level -= event.amount
event.succeed()
class Resource(base.BaseResource):
"""A resource has a limited number of slots that can be requested by
a process.
If all slots are taken, requesters are put into a queue. If a process
releases a slot, the next process is popped from the queue and gets one
slot.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
resource is bound to.
The *capacity* defines the number of slots and must be a positive integer.
"""
def __init__(self, env, capacity=1):
super(Resource, self).__init__(env)
self._capacity = capacity
self.users = []
"""List of :class:`Request` events for the processes that are currently
using the resource."""
self.queue = self.put_queue
"""Queue/list of pending :class:`Request` events that represent
processes waiting to use the resource."""
@property
def capacity(self):
"""Maximum capacity of the resource."""
return self._capacity
@property
def count(self):
"""Number of users currently using the resource."""
return len(self.users)
request = BoundClass(Request)
"""Create a new :class:`Request` event."""
release = BoundClass(Release)
"""Create a new :class:`Release` event."""
def _do_put(self, event):
if len(self.users) < self.capacity:
self.users.append(event)
event.succeed()
def _do_get(self, event):
try:
self.users.remove(event.request)
except ValueError:
pass
event.succeed()
class Container(base.BaseResource):
"""Resource containing up to *capacity* of matter which may either be
continuous (like water) or discrete (like apples). It supports requests to
put or get matter into/from the container.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
The *capacity* defines the size of the container. By default, a container
is of unlimited size. The initial amount of matter is specified by *init*
and defaults to ``0``.
Raise a :exc:`ValueError` if ``capacity <= 0``, ``init < 0`` or
``init > capacity``.
"""
def __init__(self, env, capacity=float('inf'), init=0):
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
if init < 0:
raise ValueError('"init" must be >= 0.')
if init > capacity:
raise ValueError('"init" must be <= "capacity".')
super(Container, self).__init__(env, capacity)
self._level = init
@property
def level(self):
"""The current amount of the matter in the container."""
return self._level
put = BoundClass(ContainerPut)
"""Request to put *amount* of matter into the container."""
get = BoundClass(ContainerGet)
"""Request to get *amount* of matter out of the container."""
def _do_put(self, event):
if self._capacity - self._level >= event.amount:
self._level += event.amount
event.succeed()
return True
def _do_get(self, event):
if self._level >= event.amount:
self._level -= event.amount
event.succeed()
return True
class StampedStore(base.BaseResource):
"""Models the production and consumption of concrete Python objects.
Items put into the store can be of any type. By default, they are put and
retrieved from the store in a first-in first-out order.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
The *capacity* defines the size of the Store and must be a positive number
(> 0). By default, a Store is of unlimited size. A :exc:`ValueError` is
raised if the value is negative.
"""
def __init__(self, env, capacity=float('inf')):
super(StampedStore, self).__init__(env, capacity=float('inf'))
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
self._capacity = capacity
self.items = [] # we are keeping items sorted by stamp
self.event_count = 0 # Used to break ties with python heap implementation
# See: https://docs.python.org/3/library/heapq.html?highlight=heappush#priority-queue-implementation-notes
"""List of the items within the store."""
@property
def capacity(self):
"""The maximum capacity of the store."""
return self._capacity
put = BoundClass(StampedStorePut)
"""Create a new :class:`StorePut` event."""
get = BoundClass(StampedStoreGet)
"""Create a new :class:`StoreGet` event."""
# We assume the item is a tuple: (stamp, packet). The stamp is used to
# sort the packet in the heap.
def _do_put(self, event):
self.event_count += 1 # Needed this to break heap ties
if len(self.items) < self._capacity:
heappush(self.items,
[event.item[0], self.event_count, event.item[1]])
event.succeed()
# When we return an item from the stamped store we do not
# return the stamp but only the content portion.
def _do_get(self, event):
if self.items:
event.succeed(heappop(self.items)[2])
class PriorityPool(Pool):
"""Pool with prioritizied put() and get() requests.
A priority is provided with `put()` and `get()` requests. This priority
determines the strict order in which requests are fulfilled. Requests of
the same priority are serviced in strict FIFO order.
"""
def __init__(self,
env,
capacity=float('inf'),
init=0,
hard_cap=False,
name=None):
super(PriorityPool, self).__init__(env, capacity, init, hard_cap, name)
self._event_count = 0
#: Put amount in the pool.
put = BoundClass(PriorityPoolPutEvent)
#: Get amount from the pool.
get = BoundClass(PriorityPoolGetEvent)
def _trigger_put(self, _=None):
while self._put_waiters:
put_ev = self._put_waiters[0]
if self.capacity - self.level >= put_ev.amount:
heapq.heappop(self._put_waiters)
self.level += put_ev.amount
put_ev.succeed()
if self._put_hook:
self._put_hook()
elif self._hard_cap:
raise OverflowError()
else:
break
def _trigger_get(self, _=None):
while self._get_waiters:
get_ev = self._get_waiters[0]
if get_ev.amount <= self.level:
heapq.heappop(self._get_waiters)
self.level -= get_ev.amount
get_ev.succeed(get_ev.amount)
if self._get_hook:
self._get_hook()
else:
break
class ReadableFilterStore(FilterStore):
"""Extends simpy.resources.store.FilterStore with a non-destructive read()
method."""
get = BoundClass(FilterStoreGetWithRemove)
read = BoundClass(FilterStoreGetWithNoRemove)
def _do_get(self, event):
for item in self.items:
if event.filter(item):
if event.remove_item:
self.items.remove(item)
event.succeed(item)
break
return True
class FilterQueue(Queue[ItemType]):
"""Specialized queue where items are dequeued in priority order.
Items in `PriorityQueue` must be orderable (implement
:meth:`~object.__lt__`). Unorderable items may be used with `PriorityQueue`
by wrapping with :class:`~PriorityItem`.
Items that evaluate less-than other items will be dequeued first.
"""
if TYPE_CHECKING:
def get(self,filter: Callable[[Any], bool] = lambda item: True) -> FilterQueueGet:
"""Dequeue an item from the queue."""
...
else:
get = BoundClass(FilterQueueGet)
def _trigger_get(self, _: Optional[Event] = None,*args,**kwargs) -> None:
idx = 0
while self._get_waiters and idx < len(self._get_waiters):
get_ev = self._get_waiters[idx]
for i,item in enumerate(self.items):
if get_ev.filter(item):
self.items.pop(i)
self._get_waiters.pop(idx)
get_ev.succeed(item,*args,**kwargs)
if self._get_hook:
self._get_hook()
break
else:
idx +=1
class DPStore(store.Store):
if TYPE_CHECKING:
def get(
self, epsilon: float, block_nr: int
) -> DPStoreGet:
"""Request to get an *item*, for which *filter* returns ``True``,
out of the store."""
return DPStoreGet(self, epsilon, block_nr )
else:
get = BoundClass(DPStoreGet)
def _do_get( # type: ignore[override] # noqa: F821
self, event: DPStoreGet
) -> Optional[bool]:
if len(self.items) >= event.block_nr:
return_blocks = []
for i in random.sample(range(len(self.items)), k=event.block_nr):
block = self.items[i]
if block["epsilon"] - event.epsilon <0:
block["epsilon"] = -1
else:
block["epsilon"] = block["epsilon"] - event.epsilon
return_blocks.append(block)
event.succeed(return_blocks)
return True
class Pkt(simpy.resources.store.Store):
get = BoundClass(PktRX)
def _do_get(self, event):
if self.items:
event.succeed(self.items)
self.items = []
class ModifiedContainer(simpy.Container):
def __init__(self, env, capacity, init, name, owner, resource):
super().__init__(env,capacity, init)
self.name = name
self.owner = owner
self.resource = resource
if TYPE_CHECKING:
def put( # type: ignore[override] # noqa: F821
self, amount: ContainerAmount, name: str, owner, resource: str
) -> ModifiedContainerPut:
"""Request to put *amount* of matter into the container."""
return ModifiedContainerPut(self, amount, self.name, self.owner, self.resource)
def get( # type: ignore[override] # noqa: F821
self, amount: ContainerAmount, name: str, owner, resource: str
) -> ModifiedContainerGet:
"""Request to get *amount* of matter out of the container."""
return ModifiedContainerGet(self, amount, self.name, self.owner, self.resource)
else:
put = BoundClass(ModifiedContainerPut)
get = BoundClass(ModifiedContainerGet)
def _do_put(self, event: ModifiedContainerPut) -> Optional[bool]:
if self._capacity - self._level >= event.amount:
self._level += event.amount
event.succeed()
evnt_logger.info(f"\t {self.name} of {self.owner}'s level increased by {event.amount} {self.resource}'",extra={"sim_time":self._env.now})
return True
else:
evnt_logger.info(f"\t {self.name} of {self.owner}'s put failed.'",extra={"sim_time":self._env.now})
return None
def _do_get(self, event: ModifiedContainerGet) -> Optional[bool]:
if self._level >= event.amount:
self._level -= event.amount
event.succeed()
evnt_logger.info(f"\t {self.name} of {self.owner}'s level decreased by {event.amount} {self.resource}'",extra={"sim_time":self._env.now})
return True
else:
evnt_logger.info(f"\t {self.name} of {self.owner}'s put failed.'",extra={"sim_time":self._env.now})
return None
class Store(base.BaseResource):
"""Resource with *capacity* slots for storing arbitrary objects. By
default, the *capacity* is unlimited and objects are put and retrieved from
the store in a first-in first-out order.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
"""
def __init__(self,
env: Environment,
capacity: Union[float, int] = float('inf')):
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
super().__init__(env, capacity)
self.items: List[Any] = []
"""List of the items available in the store."""
if TYPE_CHECKING:
def put( # type: ignore[override] # noqa: F821
self, item: Any) -> StorePut:
"""Request to put *item* into the store."""
return StorePut(self, item)
def get(self) -> StoreGet: # type: ignore[override] # noqa: F821
"""Request to get an *item* out of the store."""
return StoreGet(self)
else:
put = BoundClass(StorePut)
get = BoundClass(StoreGet)
def _do_put(self, event: StorePut) -> Optional[bool]:
if len(self.items) < self._capacity:
self.items.append(event.item)
event.succeed()
return None
def _do_get(self, event: StoreGet) -> Optional[bool]:
if self.items:
event.succeed(self.items.pop(0))
return None
class Store(base.BaseResource):
"""Models the production and consumption of concrete Python objects.
Items put into the store can be of any type. By default, they are put and
retrieved from the store in a first-in first-out order.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
The *capacity* defines the size of the Store and must be a positive number
(> 0). By default, a Store is of unlimited size. A :exc:`ValueError` is
raised if the value is negative.
"""
def __init__(self, env, capacity=float('inf')):
super(Store, self).__init__(env)
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
self._capacity = capacity
self.items = []
"""List of the items within the store."""
@property
def capacity(self):
"""The maximum capacity of the store."""
return self._capacity
put = BoundClass(StorePut)
"""Create a new :class:`StorePut` event."""
get = BoundClass(StoreGet)
"""Create a new :class:`StoreGet` event."""
def _do_put(self, event):
if len(self.items) < self._capacity:
self.items.append(event.item)
event.succeed()
def _do_get(self, event):
if self.items:
event.succeed(self.items.pop(0))
class PriorityResource(Resource):
"""A :class:`~simpy.resources.resource.Resource` supporting prioritized
requests.
Pending requests in the :attr:`~Resource.queue` are sorted in ascending
order by their *priority* (that means lower values are more important).
"""
PutQueue = SortedQueue
"""Type of the put queue. See
:attr:`~simpy.resources.base.BaseResource.put_queue` for details."""
GetQueue = list
"""Type of the get queue. See
:attr:`~simpy.resources.base.BaseResource.get_queue` for details."""
def __init__(self, env, capacity=1):
super(PriorityResource, self).__init__(env, capacity)
request = BoundClass(PriorityRequest)
"""Request a usage slot with the given *priority*."""
release = BoundClass(Release)
"""Release a usage slot."""
class PriorityResource(Resource):
"""A :class:`~simpy.resources.resource.Resource` supporting prioritized
requests.
Pending requests in the :attr:`~Resource.queue` are sorted in ascending
order by their *priority* (that means lower values are more important).
"""
PutQueue = SortedQueue
"""Type of the put queue. See
:attr:`~simpy.resources.base.BaseResource.put_queue` for details."""
GetQueue = list
"""Type of the get queue. See
:attr:`~simpy.resources.base.BaseResource.get_queue` for details."""
def __init__(self, env: Environment, capacity: int = 1):
super().__init__(env, capacity)
if TYPE_CHECKING:
def request(
self, priority: int = 0, preempt: bool = True
) -> PriorityRequest:
"""Request a usage slot with the given *priority*."""
return PriorityRequest(self, priority, preempt)
def release( # type: ignore[override] # noqa: F821
self, request: PriorityRequest
) -> Release:
"""Release a usage slot."""
return Release(self, request)
else:
request = BoundClass(PriorityRequest)
release = BoundClass(Release)
class Pkt(simpy.resources.store.Store):
get = BoundClass(PktRX)
def _do_get (self, event):
if self.items:
# if no limit - fetch all
if event.limit is None:
event.succeed(self.items)
self.items = []
else:
# if limit was set - slice the list
event.succeed(self.items[:event.limit])
self.items = self.items[event.limit:]
class FilterStore(Store):
"""Resource with *capacity* slots for storing arbitrary objects supporting
filtered get requests. Like the :class:`Store`, the *capacity* is unlimited
by default and objects are put and retrieved from the store in a first-in
first-out order.
Get requests can be customized with a filter function to only trigger for
items for which said filter function returns ``True``.
.. note::
In contrast to :class:`Store`, get requests of a :class:`FilterStore`
won't necessarily be triggered in the same order they were issued.
*Example:* The store is empty. *Process 1* tries to get an item of type
*a*, *Process 2* an item of type *b*. Another process puts one item of
type *b* into the store. Though *Process 2* made his request after
*Process 1*, it will receive that new item because *Process 1* doesn't
want it.
"""
if TYPE_CHECKING:
def get(
self,
filter: Callable[[Any],
bool] = lambda item: True) -> FilterStoreGet:
"""Request to get an *item*, for which *filter* returns ``True``,
out of the store."""
return FilterStoreGet(self, filter)
else:
get = BoundClass(FilterStoreGet)
def _do_get( # type: ignore[override] # noqa: F821
self, event: FilterStoreGet) -> Optional[bool]:
for item in self.items:
if event.filter(item):
self.items.remove(item)
event.succeed(item)
break
return True
class PriorityResource(Resource):
"""This class works like :class:`Resource`, but requests are sorted by
priority.
The :attr:`~Resource.queue` is kept sorted by priority in ascending order
(a lower value for *priority* results in a higher priority), so more
important request will get the resource earlier.
"""
PutQueue = SortedQueue
"""The type to be used for the
:attr:`~simpy.resources.base.BaseResource.put_queue`."""
GetQueue = list
"""The type to be used for the
:attr:`~simpy.resources.base.BaseResource.get_queue`."""
def __init__(self, env, capacity=1):
super(PriorityResource, self).__init__(env, capacity)
request = BoundClass(PriorityRequest)
"""Create a new :class:`PriorityRequest` event."""
class FilterStore(Store):
"""The *FilterStore* subclasses :class:`Store` and allows you to only get
items that match a user-defined criteria.
This criteria is defined via a filter function that is passed to
:meth:`get()`. :meth:`get()` only considers items for which this function
returns ``True``.
.. note::
In contrast to :class:`Store`, processes trying to get an item from
:class:`FilterStore` won't necessarily be processed in the same order
that they made the request.
*Example:* The store is empty. *Process 1* tries to get an item of type
*a*, *Process 2* an item of type *b*. Another process puts one item of
type *b* into the store. Though *Process 2* made his request after
*Process 1*, it will receive that new item because *Process 1* doesn't
want it.
"""
GetQueue = FilterQueue
"""The type to be used for the
:attr:`~simpy.resources.base.BaseResource.get_queue`."""
def __init__(self, env, capacity=float('inf')):
super(FilterStore, self).__init__(env, capacity)
self.get_queue.store = self
get = BoundClass(FilterStoreGet)
"""Create a new :class:`FilterStoreGet` event."""
def _do_get(self, event):
for item in self.items:
if event.filter(item):
self.items.remove(item)
event.succeed(item)
break
class HdlEnvironmentCore(Environment):
"""
Simpy Environment with patched processes to allow propcess start priotiry tweaks
"""
process = BoundClass(HdlProcess)
class Pool(object):
"""Simulation pool of discrete or continuous resources.
`Pool` is similar to :class:`simpy.resources.Container`.
It provides a simulation-aware container for managing a shared pool of
resources. The resources can be either discrete objects (like apples) or
continuous (like water).
Resources are added and removed using :meth:`put()` and :meth:`get()`.
:param env: Simulation environment.
:param capacity: Capacity of the pool; infinite by default.
:param hard_cap:
If specified, the pool overflows when the `capacity` is reached.
:param init_level: Initial level of the pool.
:param name: Optional name to associate with the queue.
"""
def __init__(self,
env,
capacity=float('inf'),
init=0,
hard_cap=False,
name=None):
self.env = env
#: Capacity of the pool (maximum level).
self.capacity = capacity
#: Current fill level of the pool.
self.level = init
self._hard_cap = hard_cap
self.name = name
self._put_waiters = []
self._get_waiters = []
self._at_most_waiters = []
self._at_least_waiters = []
self._put_hook = None
self._get_hook = None
BoundClass.bind_early(self)
@property
def remaining(self):
"""Remaining pool capacity."""
return self.capacity - self.level
@property
def is_empty(self):
"""Indicates whether the pool is empty."""
return self.level == 0
@property
def is_full(self):
"""Indicates whether the pool is full."""
return self.level >= self.capacity
#: Put amount in the pool.
put = BoundClass(PoolPutEvent)
#: Get amount from the pool.
get = BoundClass(PoolGetEvent)
#: Return and event triggered when the pool has at least `amount` items.
when_at_least = BoundClass(PoolWhenAtLeastEvent)
#: Return and event triggered when the pool has at most `amount` items.
when_at_most = BoundClass(PoolWhenAtMostEvent)
#: Return an event triggered when the pool is non-empty.
when_any = BoundClass(PoolWhenAnyEvent)
#: Return an event triggered when the pool becomes full.
when_full = BoundClass(PoolWhenFullEvent)
#: Return an event triggered when the pool becomes not full.
when_not_full = BoundClass(PoolWhenNotFullEvent)
#: Return an event triggered when the pool becomes empty.
when_empty = BoundClass(PoolWhenEmptyEvent)
def _trigger_put(self, _=None):
idx = 0
while self._put_waiters and idx < len(self._put_waiters):
put_ev = self._put_waiters[idx]
if self.capacity - self.level >= put_ev.amount:
self._put_waiters.pop(idx)
self.level += put_ev.amount
put_ev.succeed()
if self._put_hook:
self._put_hook()
elif self._hard_cap:
raise OverflowError()
else:
idx += 1
def _trigger_get(self, _=None):
idx = 0
while self._get_waiters and idx < len(self._get_waiters):
get_ev = self._get_waiters[idx]
if get_ev.amount <= self.level:
self._get_waiters.pop(idx)
self.level -= get_ev.amount
get_ev.succeed(get_ev.amount)
if self._get_hook:
self._get_hook()
else:
idx += 1
def _trigger_when_at_least(self, _=None):
while (self._at_least_waiters
and self.level >= self._at_least_waiters[0].amount):
when_at_least_ev = heapq.heappop(self._at_least_waiters)
when_at_least_ev.succeed()
def _trigger_when_at_most(self, _=None):
while (self._at_most_waiters
and self.level <= self._at_most_waiters[0].amount):
at_most_ev = heapq.heappop(self._at_most_waiters)
at_most_ev.succeed()
def __repr__(self):
return ('{0.__class__.__name__}(name={0.name!r} level={0.level}'
' capacity={0.capacity})').format(self)
class BaseResource(object):
"""This is the abstract base class for all SimPy resources.
All resources are bound to a specific :class:`~simpy.core.Environment`
*env*.
You can :meth:`put()` something into the resources or :meth:`get()`
something out of it. Both methods return an event that the requesting
process has to ``yield``.
If a put or get operation can be performed immediately (because the
resource is not full (put) or not empty (get)), that event is triggered
immediately.
If a resources is too full or too empty to perform a put or get request,
the event is pushed to the *put_queue* or *get_queue*. An event is popped
from one of these queues and triggered as soon as the corresponding
operation is possible.
:meth:`put()` and :meth:`get()` only provide the user API and the general
framework and should not be overridden in subclasses. The actual behavior
for what happens when a put/get succeeds should rather be implemented in
:meth:`_do_put()` and :meth:`_do_get()`.
"""
PutQueue = list
"""The type to be used for the :attr:`put_queue`. This can either be
a plain :class:`list` (default) or a subclass of it."""
GetQueue = list
"""The type to be used for the :attr:`get_queue`. This can either be
a plain :class:`list` (default) or a subclass of it."""
def __init__(self, env):
self._env = env
self.put_queue = self.PutQueue()
"""Queue/list of events waiting to get something out of the resource.
"""
self.get_queue = self.GetQueue()
"""Queue/list of events waiting to put something into the resource."""
# Bind event constructors as methods
BoundClass.bind_early(self)
put = BoundClass(Put)
"""Create a new :class:`Put` event."""
get = BoundClass(Get)
"""Create a new :class:`Get` event."""
def _do_put(self, event):
"""Actually perform the *put* operation.
This methods needs to be implemented by subclasses. It receives the
*put_event* that is created at each request and doesn't need to return
anything.
"""
raise NotImplementedError(self)
def _trigger_put(self, get_event):
"""Trigger pending put events after a get event has been executed."""
self.get_queue.remove(get_event)
for put_event in self.put_queue:
if not put_event.triggered:
self._do_put(put_event)
if not put_event.triggered:
break
def _do_get(self, event):
"""Actually perform the *get* operation.
This methods needs to be implemented by subclasses. It receives the
*get_event* that is created at each request and doesn't need to return
anything.
"""
raise NotImplementedError(self)
def _trigger_get(self, put_event):
"""Trigger pending get events after a put event has been executed."""
self.put_queue.remove(put_event)
for get_event in self.get_queue:
if not get_event.triggered:
self._do_get(get_event)
if not get_event.triggered:
break
class Store(BaseResource):
"""Resource with *capacity* slots for storing arbitrary objects. By
default, the *capacity* is unlimited and objects are put and retrieved from
the store in a first-in first-out order.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
"""
PeekQueue: ClassVar[Type[MutableSequence[PeekType]]] = list
GetTriggeredQueue: ClassVar[Type[MutableSequence[GetTriggeredType]]] = list
PopQueue: ClassVar[Type[MutableSequence[PopType]]] = list
PushQueue: ClassVar[Type[MutableSequence[PushType]]] = list
"""The type to be used for the :attr:`get_queue`. It is a plain
:class:`list` by default. The type must support index access (e.g.
``__getitem__()`` and ``__len__()``) as well as provide ``append()`` and
``pop()`` operations."""
def __init__(self,
env: Environment,
capacity: int = -1,
length: int = 2,
speed: int = 1,
acceleration: int = 0,
deceleration: int = 0,
distance: int = -1):
super().__init__(env, capacity)
self.peek_queue = self.PeekQueue()
self.get_triggered_queue = self.GetTriggeredQueue()
self.pop_queue = self.PopQueue()
self.push_queue = self.PushQueue()
self.length = length
self.speed = speed
self.acceleration = acceleration
self.deceleration = deceleration
self.distance = distance
self.items: List[Any] = []
"""List of the items available in the store."""
self.processing_queue: List[Any] = []
self.ready_queue: List[Any] = []
"""List of the items available in the store."""
if TYPE_CHECKING:
def put( # type: ignore[override] # noqa: F821
self, item: Any) -> StorePut:
"""Request to put *item* into the store."""
return StorePut(self, item)
def get(self,
item: Any) -> StoreGet: # type: ignore[override] # noqa: F821
"""Request to get an *item* out of the store."""
return StoreGet(self, item)
def peek(self) -> StorePeek:
return StorePeek(self)
def get_triggered(self) -> StoreGetTriggered:
return StoreGetTriggered(self)
def pop(self) -> StorePop:
return StorePop(self)
def push(self) -> StorePush:
return StorePush(self)
else:
put = BoundClass(StorePut)
get = BoundClass(StoreGet)
peek = BoundClass(StorePeek)
get_triggered = BoundClass(StoreGetTriggered)
pop = BoundClass(StorePop)
push = BoundClass(StorePush)
def _get_duration(self):
return self.length / self.speed
def _check_distance(self):
if self.distance == -1:
return 0
elif len(self.processing_queue) == 0:
return 0
else:
return (self.distance -
(self._env.now - self.processing_queue[-1]["startTime"]) *
self.speed) / self.speed
def _check_capacity(self):
if self.capacity == -1:
return 0
elif len(self.processing_queue) < self.capacity:
return 0
else:
return self._get_duration() - (
self._env.now - self.processing_queue[0]["startTime"])
def _capacity_available(self):
if self.capacity == -1:
return True
elif len(self.processing_queue) < self.capacity:
return True
else:
return False
def _check_available(self):
return self._check_distance() <= 0 and self._check_capacity(
) <= 0 and self._capacity_available()
def _do_put(self, event: StorePut) -> Optional[bool]:
if self._check_available():
self.processing_queue.append({
"data": event.item,
"startTime": self._env.now
})
event.succeed(True)
return None
def _do_get(self, event: StoreGet) -> Optional[bool]:
if self.processing_queue[event.item]:
event.succeed(self.processing_queue[event.item])
return None
def _do_peek(self, event: StorePeek) -> Optional[bool]:
if self.items:
event.succeed(self.items[0])
return None
def _do_get_triggered(self, event: StoreGetTriggered) -> Optional[bool]:
if self._check_available():
event.succeed(True)
return None
def _do_pop(self, event: StorePop) -> Optional[bool]:
if self.ready_queue:
event.succeed(self.ready_queue.pop(0))
self.processing_queue.pop(0)
return None
def _do_push(self, event: StorePush) -> Optional[bool]:
self.ready_queue.append(event.item)
event.succeed(True)
return None
def _trigger_peek(self, put_event: Optional[PutType]) -> None:
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.peek_queue):
peek_event = self.peek_queue[idx]
proceed = self._do_peek(peek_event)
if not peek_event.triggered:
idx += 1
elif self.peek_queue.pop(idx) != peek_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
def _trigger_get_triggered(self, get_event: Optional[GetType]) -> None:
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.get_triggered_queue):
get_triggered_event = self.get_triggered_queue[idx]
proceed = self._do_get_triggered(get_triggered_event)
if not get_triggered_event.triggered:
idx += 1
elif self.get_triggered_queue.pop(idx) != get_triggered_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
def _trigger_pop(self, get_event: Optional[GetType]) -> None:
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.pop_queue):
pop_event = self.pop_queue[idx]
proceed = self._do_pop(pop_event)
if not pop_event.triggered:
idx += 1
elif self.pop_queue.pop(idx) != pop_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
def _trigger_push(self, get_event: Optional[GetType]) -> None:
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.push_queue):
push_event = self.push_queue[idx]
proceed = self._do_push(push_event)
if not push_event.triggered:
idx += 1
elif self.push_queue.pop(idx) != push_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
class Store(BaseResource):
"""Resource with *capacity* slots for storing arbitrary objects. By
default, the *capacity* is unlimited and objects are put and retrieved from
the store in a first-in first-out order.
The *env* parameter is the :class:`~simpy.core.Environment` instance the
container is bound to.
"""
PeekQueue: ClassVar[Type[MutableSequence[PeekType]]] = list
GetTriggeredQueue: ClassVar[Type[MutableSequence[GetTriggeredType]]] = list
"""The type to be used for the :attr:`get_queue`. It is a plain
:class:`list` by default. The type must support index access (e.g.
``__getitem__()`` and ``__len__()``) as well as provide ``append()`` and
``pop()`` operations."""
def __init__(self,
env: Environment,
capacity: Union[float, int] = float('inf')):
if capacity <= 0:
raise ValueError('"capacity" must be > 0.')
self.peek_queue = self.PeekQueue()
self.get_triggered_queue = self.GetTriggeredQueue()
super().__init__(env, capacity)
self.items: List[Any] = []
"""List of the items available in the store."""
if TYPE_CHECKING:
def put( # type: ignore[override] # noqa: F821
self, item: Any) -> StorePut:
"""Request to put *item* into the store."""
return StorePut(self, item)
def get(self) -> StoreGet: # type: ignore[override] # noqa: F821
"""Request to get an *item* out of the store."""
return StoreGet(self)
def peek(self) -> StorePeek:
return StorePeek(self)
def get_triggered(self) -> StoreGetTriggered:
return StoreGetTriggered(self)
else:
put = BoundClass(StorePut)
get = BoundClass(StoreGet)
peek = BoundClass(StorePeek)
get_triggered = BoundClass(StoreGetTriggered)
def _do_put(self, event: StorePut) -> Optional[bool]:
if len(self.items) < self._capacity:
self.items.append(event.item)
event.succeed(True)
return None
def _do_get(self, event: StoreGet) -> Optional[bool]:
if self.items:
event.succeed(self.items.pop(0))
return None
def _do_peek(self, event: StorePeek) -> Optional[bool]:
if self.items:
event.succeed(self.items[0])
return None
def _do_get_triggered(self, event: StoreGetTriggered) -> Optional[bool]:
if not self.items:
event.succeed(True)
return None
def _trigger_peek(self, put_event: Optional[PutType]) -> None:
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.peek_queue):
peek_event = self.peek_queue[idx]
proceed = self._do_peek(peek_event)
if not peek_event.triggered:
idx += 1
elif self.peek_queue.pop(idx) != peek_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
def _trigger_get_triggered(self, get_event: Optional[GetType]) -> None:
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.get_triggered_queue):
get_triggered_event = self.get_triggered_queue[idx]
proceed = self._do_get_triggered(get_triggered_event)
if not get_triggered_event.triggered:
idx += 1
elif self.get_triggered_queue.pop(idx) != get_triggered_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
def _trigger_put(self, get_event: Optional[GetType]) -> None:
"""This method is called once a new put event has been created or a get
event has been processed.
The method iterates over all put events in the :attr:`put_queue` and
calls :meth:`_do_put` to check if the conditions for the event are met.
If :meth:`_do_put` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All put requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.put_queue):
put_event = self.put_queue[idx]
proceed = self._do_put(put_event)
if not put_event.triggered:
idx += 1
elif self.put_queue.pop(idx) != put_event:
raise RuntimeError('Put queue invariant violated')
if not proceed:
break
def _trigger_get(self, put_event: Optional[PutType]) -> None:
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.get_queue):
get_event = self.get_queue[idx]
proceed = self._do_get(get_event)
if not get_event.triggered:
idx += 1
elif self.get_queue.pop(idx) != get_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
class Queue(Generic[ItemType]):
"""Simulation queue of arbitrary items.
`Queue` is similar to :class:`simpy.Store`. It provides a simulation-aware
first-in first-out (FIFO) queue useful for passing messages between
simulation processes or managing a pool of objects needed by multiple
processes.
Items are enqueued and dequeued using :meth:`put()` and :meth:`get()`.
:param env: Simulation environment.
:param capacity: Capacity of the queue; infinite by default.
:param hard_cap:
If specified, the queue overflows when the `capacity` is reached.
:param items: Optional sequence of items to pre-populate the queue.
:param name: Optional name to associate with the queue.
"""
def __init__(
self,
env: Environment,
capacity: Union[int, float] = float('inf'),
hard_cap: bool = False,
items: Iterable[ItemType] = (),
name: Optional[str] = None,
) -> None:
self.env = env
#: Capacity of the queue (maximum number of items).
self.capacity = capacity
self._hard_cap = hard_cap
self.items: List[ItemType] = list(items)
self.name = name
self._put_waiters: List[QueuePutEvent] = []
self._get_waiters: List[QueueGetEvent] = []
self._at_most_waiters: List[QueueWhenAtMostEvent] = []
self._at_least_waiters: List[QueueWhenAtLeastEvent] = []
self._put_hook: Optional[Callable[[], Any]] = None
self._get_hook: Optional[Callable[[], Any]] = None
BoundClass.bind_early(self)
@property
def size(self) -> int:
"""Number of items in queue."""
return len(self.items)
@property
def remaining(self) -> Union[int, float]:
"""Remaining queue capacity."""
return self.capacity - len(self.items)
@property
def is_empty(self) -> bool:
"""Indicates whether the queue is empty."""
return not self.items
@property
def is_full(self) -> bool:
"""Indicates whether the queue is full."""
return len(self.items) >= self.capacity
def peek(self) -> ItemType:
"""Peek at the next item in the queue."""
return self.items[0]
if TYPE_CHECKING:
def put(self, item: ItemType) -> QueuePutEvent:
"""Enqueue an item on the queue."""
...
def get(self) -> QueueGetEvent:
"""Dequeue an item from the queue."""
...
def when_at_least(self, num_items: int) -> QueueWhenAtLeastEvent:
"""Return an event triggered when the queue has at least n items."""
...
def when_at_most(self, num_items: int) -> QueueWhenAtMostEvent:
"""Return an event triggered when the queue has at most n items."""
...
def when_any(self) -> QueueWhenAnyEvent:
"""Return an event triggered when the queue is non-empty."""
...
def when_full(self) -> QueueWhenFullEvent:
"""Return an event triggered when the queue becomes full."""
...
def when_not_full(self) -> QueueWhenNotFullEvent:
"""Return an event triggered when the queue becomes not full."""
...
def when_empty(self) -> QueueWhenEmptyEvent:
"""Return an event triggered when the queue becomes empty."""
...
else:
put = BoundClass(QueuePutEvent)
get = BoundClass(QueueGetEvent)
when_at_least = BoundClass(QueueWhenAtLeastEvent)
when_at_most = BoundClass(QueueWhenAtMostEvent)
when_any = BoundClass(QueueWhenAnyEvent)
when_full = BoundClass(QueueWhenFullEvent)
when_not_full = BoundClass(QueueWhenNotFullEvent)
when_empty = BoundClass(QueueWhenEmptyEvent)
def _enqueue_item(self, item: ItemType) -> None:
self.items.append(item)
def _dequeue_item(self) -> ItemType:
return self.items.pop(0)
def _trigger_put(self, _: Optional[Event] = None) -> None:
while self._put_waiters:
if len(self.items) < self.capacity:
put_ev = self._put_waiters.pop(0)
self._enqueue_item(put_ev.item)
put_ev.succeed()
if self._put_hook:
self._put_hook()
elif self._hard_cap:
raise OverflowError()
else:
break
def _trigger_get(self, _: Optional[Event] = None) -> None:
while self._get_waiters and self.items:
get_ev = self._get_waiters.pop(0)
item = self._dequeue_item()
get_ev.succeed(item)
if self._get_hook:
self._get_hook()
def _trigger_when_at_least(self, _: Optional[Event] = None, *args, **kwargs) -> None:
while (
self._at_least_waiters and self.size >= self._at_least_waiters[0].num_items
):
when_at_least_ev = heappop(self._at_least_waiters)
when_at_least_ev.succeed(*args,**kwargs)
def _trigger_when_at_most(self, _: Optional[Event] = None) -> None:
while self._at_most_waiters and self.size <= self._at_most_waiters[0].num_items:
at_most_ev = heappop(self._at_most_waiters)
at_most_ev.succeed()
def __repr__(self) -> str:
return (
f'{self.__class__.__name__}('
f'name={self.name!r} size={self.size} capacity={self.capacity})'
)
class BaseResource(object):
"""Abstract base class for a shared resource.
You can :meth:`put()` something into the resources or :meth:`get()`
something out of it. Both methods return an event that is triggered once
the operation is completed. If a :meth:`put()` request cannot complete
immediately (for example if the resource has reached a capacity limit) it
is enqueued in the :attr:`put_queue` for later processing. Likewise for
:meth:`get()` requests.
Subclasses can customize the resource by:
- providing custom :attr:`PutQueue` and :attr:`GetQueue` types,
- providing custom :class:`Put` respectively :class:`Get` events,
- and implementing the request processing behaviour through the methods
``_do_get()`` and ``_do_put()``.
"""
PutQueue = list
"""The type to be used for the :attr:`put_queue`. It is a plain
:class:`list` by default. The type must support index access (e.g.
``__getitem__()`` and ``__len__()``) as well as provide ``append()`` and
``pop()`` operations."""
GetQueue = list
"""The type to be used for the :attr:`get_queue`. It is a plain
:class:`list` by default. The type must support index access (e.g.
``__getitem__()`` and ``__len__()``) as well as provide ``append()`` and
``pop()`` operations."""
def __init__(self, env, capacity):
self._env = env
self._capacity = capacity
self.put_queue = self.PutQueue()
"""Queue of pending *put* requests."""
self.get_queue = self.GetQueue()
"""Queue of pending *get* requests."""
# Bind event constructors as methods
BoundClass.bind_early(self)
@property
def capacity(self):
"""Maximum capacity of the resource."""
return self._capacity
put = BoundClass(Put)
"""Request to put something into the resource and return a :class:`Put`
event, which gets triggered once the request succeeds."""
get = BoundClass(Get)
"""Request to get something from the resource and return a :class:`Get`
event, which gets triggered once the request succeeds."""
def _do_put(self, event):
"""Perform the *put* operation.
This method needs to be implemented by subclasses. If the conditions
for the put *event* are met, the method must trigger the event (e.g.
call :meth:`Event.succeed()` with an apropriate value).
This method is called by :meth:`_trigger_put` for every event in the
:attr:`put_queue`, as long as the return value does not evaluate
``False``.
"""
raise NotImplementedError(self)
def _trigger_put(self, get_event):
"""This method is called once a new put event has been created or a get
event has been processed.
The method iterates over all put events in the :attr:`put_queue` and
calls :meth:`_do_put` to check if the conditions for the event are met.
If :meth:`_do_put` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All put requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.put_queue):
put_event = self.put_queue[idx]
proceed = self._do_put(put_event)
if not put_event.triggered:
idx += 1
elif self.put_queue.pop(idx) != put_event:
raise RuntimeError('Put queue invariant violated')
if not proceed:
break
def _do_get(self, event):
"""Perform the *get* operation.
This method needs to be implemented by subclasses. If the conditions
for the get *event* are met, the method must trigger the event (e.g.
call :meth:`Event.succeed()` with an apropriate value).
This method is called by :meth:`_trigger_get` for every event in the
:attr:`get_queue`, as long as the return value does not evaluate
``False``.
"""
raise NotImplementedError(self)
def _trigger_get(self, put_event):
"""Trigger get events.
This method is called once a new get event has been created or a put
event has been processed.
The method iterates over all get events in the :attr:`get_queue` and
calls :meth:`_do_get` to check if the conditions for the event are met.
If :meth:`_do_get` returns ``False``, the iteration is stopped early.
"""
# Maintain queue invariant: All get requests must be untriggered.
# This code is not very pythonic because the queue interface should be
# simple (only append(), pop(), __getitem__() and __len__() are
# required).
idx = 0
while idx < len(self.get_queue):
get_event = self.get_queue[idx]
proceed = self._do_get(get_event)
if not get_event.triggered:
idx += 1
elif self.get_queue.pop(idx) != get_event:
raise RuntimeError('Get queue invariant violated')
if not proceed:
break
class Queue(object):
"""Simulation queue of arbitrary items.
`Queue` is similar to :class:`simpy.Store`. It provides a simulation-aware
first-in first-out (FIFO) queue useful for passing messages between
simulation processes or managing a pool of objects needed by multiple
processes.
Items are enqueued and dequeued using :meth:`put()` and :meth:`get()`.
:param env: Simulation environment.
:param capacity: Capacity of the queue; infinite by default.
:param hard_cap:
If specified, the queue overflows when the `capacity` is reached.
:param items: Optional sequence of items to pre-populate the queue.
:param name: Optional name to associate with the queue.
"""
def __init__(self,
env,
capacity=float('inf'),
hard_cap=False,
items=(),
name=None):
self.env = env
#: Capacity of the queue (maximum number of items).
self.capacity = capacity
self._hard_cap = hard_cap
self.items = list(items)
self.name = name
self._putters = []
self._getters = []
self._new_waiters = []
self._any_waiters = []
self._full_waiters = []
self._put_hook = None
self._get_hook = None
BoundClass.bind_early(self)
@property
def size(self):
"""Number of items in queue."""
return len(self.items)
@property
def remaining(self):
"""Remaining queue capacity."""
return self.capacity - len(self.items)
@property
def is_empty(self):
"""Indicates whether the queue is empty."""
return not self.items
@property
def is_full(self):
"""Indicates whether the queue is full."""
return len(self.items) >= self.capacity
def peek(self):
"""Peek at the next item in the queue."""
return self.items[0]
#: Enqueue an item on the queue.
put = BoundClass(QueuePutEvent)
#: Dequeue an item from the queue.
get = BoundClass(QueueGetEvent)
#: Return an event triggered when a new item is put into the queue.
when_new = BoundClass(QueueWhenNewEvent)
#: Return an event triggered when the queue is non-empty.
when_any = BoundClass(QueueWhenAnyEvent)
#: Return an event triggered when the queue becomes full.
when_full = BoundClass(QueueWhenFullEvent)
def _enqueue_item(self, item):
self.items.append(item)
def _dequeue_item(self):
return self.items.pop(0)
def _trigger_put(self, _=None):
if self._putters:
if len(self.items) < self.capacity:
put_ev = self._putters.pop(0)
put_ev.succeed()
self._enqueue_item(put_ev.item)
self._trigger_when_new()
self._trigger_when_any()
self._trigger_when_full()
if self._put_hook:
self._put_hook()
elif self._hard_cap:
raise OverflowError()
def _trigger_get(self, _=None):
if self._getters and self.items:
get_ev = self._getters.pop(0)
item = self._dequeue_item()
get_ev.succeed(item)
if self._get_hook:
self._get_hook()
def _trigger_when_new(self):
for when_new_ev in self._new_waiters:
when_new_ev.succeed()
del self._new_waiters[:]
def _trigger_when_any(self):
if self.items:
for when_any_ev in self._any_waiters:
when_any_ev.succeed()
del self._any_waiters[:]
def _trigger_when_full(self):
if len(self.items) == self.capacity:
for when_full_ev in self._full_waiters:
when_full_ev.succeed()
del self._full_waiters[:]
def __str__(self):
return ('Queue: name={0.name}'
' size={1}'
' capacity={0.capacity}'
')'.format(self, len(self.items)))