nonebot2/nonebot/message.py
2020-12-19 14:16:47 +08:00

269 lines
8.2 KiB
Python

"""
事件处理
========
NoneBot 内部处理并按优先级分发事件给所有事件响应器,提供了多个插槽以进行事件的预处理等。
"""
import asyncio
from datetime import datetime
from typing import Set, Type, Optional, Iterable, TYPE_CHECKING
from nonebot.log import logger
from nonebot.rule import TrieRule
from nonebot.matcher import matchers, Matcher
from nonebot.exception import IgnoredException, StopPropagation, NoLogException
from nonebot.typing import T_State, T_EventPreProcessor, T_RunPreProcessor, T_EventPostProcessor, T_RunPostProcessor
if TYPE_CHECKING:
from nonebot.adapters import Bot, Event
_event_preprocessors: Set[T_EventPreProcessor] = set()
_event_postprocessors: Set[T_EventPostProcessor] = set()
_run_preprocessors: Set[T_RunPreProcessor] = set()
_run_postprocessors: Set[T_RunPostProcessor] = set()
def event_preprocessor(func: T_EventPreProcessor) -> T_EventPreProcessor:
"""
:说明:
事件预处理。装饰一个函数,使它在每次接收到事件并分发给各响应器之前执行。
:参数:
事件预处理函数接收三个参数。
* ``bot: Bot``: Bot 对象
* ``event: Event``: Event 对象
* ``state: T_State``: 当前 State
"""
_event_preprocessors.add(func)
return func
def event_postprocessor(func: T_EventPostProcessor) -> T_EventPostProcessor:
"""
:说明:
事件后处理。装饰一个函数,使它在每次接收到事件并分发给各响应器之后执行。
:参数:
事件后处理函数接收三个参数。
* ``bot: Bot``: Bot 对象
* ``event: Event``: Event 对象
* ``state: T_State``: 当前事件运行前 State
"""
_event_postprocessors.add(func)
return func
def run_preprocessor(func: T_RunPreProcessor) -> T_RunPreProcessor:
"""
:说明:
运行预处理。装饰一个函数,使它在每次事件响应器运行前执行。
:参数:
运行预处理函数接收四个参数。
* ``matcher: Matcher``: 当前要运行的事件响应器
* ``bot: Bot``: Bot 对象
* ``event: Event``: Event 对象
* ``state: T_State``: 当前 State
"""
_run_preprocessors.add(func)
return func
def run_postprocessor(func: T_RunPostProcessor) -> T_RunPostProcessor:
"""
:说明:
运行后处理。装饰一个函数,使它在每次事件响应器运行后执行。
:参数:
运行后处理函数接收五个参数。
* ``matcher: Matcher``: 运行完毕的事件响应器
* ``exception: Optional[Exception]``: 事件响应器运行错误(如果存在)
* ``bot: Bot``: Bot 对象
* ``event: Event``: Event 对象
* ``state: T_State``: 当前 State
"""
_run_postprocessors.add(func)
return func
async def _check_matcher(priority: int, bot: "Bot", event: "Event",
state: T_State) -> Iterable[Type[Matcher]]:
current_matchers = matchers[priority].copy()
async def _check(Matcher: Type[Matcher], bot: "Bot", event: "Event",
state: T_State) -> Optional[Type[Matcher]]:
try:
if (not Matcher.expire_time or datetime.now() <= Matcher.expire_time
) and await Matcher.check_perm(
bot, event) and await Matcher.check_rule(bot, event, state):
return Matcher
except Exception as e:
logger.opt(colors=True, exception=e).error(
f"<r><bg #f8bbd0>Rule check failed for {Matcher}.</bg #f8bbd0></r>"
)
return None
async def _check_expire(Matcher: Type[Matcher]) -> Optional[Type[Matcher]]:
if Matcher.temp or (Matcher.expire_time and
datetime.now() > Matcher.expire_time):
return Matcher
return None
checking_tasks = [
_check(Matcher, bot, event, state) for Matcher in current_matchers
]
checking_expire_tasks = [
_check_expire(Matcher) for Matcher in current_matchers
]
results = await asyncio.gather(*checking_tasks, return_exceptions=True)
expired = await asyncio.gather(*checking_expire_tasks)
for expired_matcher in filter(lambda x: x, expired):
try:
matchers[priority].remove(expired_matcher) # type: ignore
except Exception:
pass
return filter(lambda x: x, results)
async def _run_matcher(Matcher: Type[Matcher], bot: "Bot", event: "Event",
state: T_State) -> None:
logger.info(f"Event will be handled by {Matcher}")
matcher = Matcher()
coros = list(
map(lambda x: x(matcher, bot, event, state), _run_preprocessors))
if coros:
try:
await asyncio.gather(*coros)
except IgnoredException:
logger.opt(colors=True).info(
f"Matcher {matcher} running is <b>cancelled</b>")
return
except Exception as e:
logger.opt(colors=True, exception=e).error(
"<r><bg #f8bbd0>Error when running RunPreProcessors. "
"Running cancelled!</bg #f8bbd0></r>")
return
exception = None
try:
logger.debug(f"Running matcher {matcher}")
await matcher.run(bot, event, state)
except StopPropagation as e:
exception = e
except Exception as e:
logger.opt(colors=True, exception=e).error(
f"<r><bg #f8bbd0>Running matcher {matcher} failed.</bg #f8bbd0></r>"
)
exception = e
coros = list(
map(lambda x: x(matcher, exception, bot, event, state),
_run_postprocessors))
if coros:
try:
await asyncio.gather(*coros)
except Exception as e:
logger.opt(colors=True, exception=e).error(
"<r><bg #f8bbd0>Error when running RunPostProcessors</bg #f8bbd0></r>"
)
if matcher.block or isinstance(exception, StopPropagation):
raise StopPropagation
return
async def handle_event(bot: "Bot", event: "Event"):
"""
:说明:
处理一个事件。调用该函数以实现分发事件。
:参数:
* ``bot: Bot``: Bot 对象
* ``event: Event``: Event 对象
:示例:
.. code-block:: python
import asyncio
asyncio.create_task(handle_event(bot, event))
"""
show_log = True
log_msg = f"<m>{bot.type.upper()} {bot.self_id}</m> | "
try:
log_msg += event.get_log_string()
except NoLogException:
show_log = False
if show_log:
logger.opt(colors=True).info(log_msg)
state = {}
coros = list(map(lambda x: x(bot, event, state), _event_preprocessors))
if coros:
try:
logger.debug("Running PreProcessors...")
await asyncio.gather(*coros)
except IgnoredException:
logger.opt(colors=True).info(
f"Event {event.get_event_name()} is <b>ignored</b>")
return
except Exception as e:
logger.opt(colors=True, exception=e).error(
"<r><bg #f8bbd0>Error when running EventPreProcessors. "
"Event ignored!</bg #f8bbd0></r>")
return
# Trie Match
_, _ = TrieRule.get_value(bot, event, state)
break_flag = False
for priority in sorted(matchers.keys()):
if break_flag:
break
if show_log:
logger.debug(f"Checking for matchers in priority {priority}...")
run_matchers = await _check_matcher(priority, bot, event, state)
pending_tasks = [
_run_matcher(matcher, bot, event, state.copy())
for matcher in run_matchers
]
results = await asyncio.gather(*pending_tasks, return_exceptions=True)
for result in results:
if isinstance(result, StopPropagation):
if not break_flag:
break_flag = True
logger.debug("Stop event propagation")
coros = list(map(lambda x: x(bot, event, state), _event_postprocessors))
if coros:
try:
logger.debug("Running PostProcessors...")
await asyncio.gather(*coros)
except Exception as e:
logger.opt(colors=True, exception=e).error(
"<r><bg #f8bbd0>Error when running EventPostProcessors</bg #f8bbd0></r>"
)