nonebot2/nonebot/message.py
2021-11-13 19:38:01 +08:00

262 lines
7.7 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 TYPE_CHECKING, Set, Type, Optional
from nonebot.log import logger
from nonebot.rule import TrieRule
from nonebot.utils import escape_tag
from nonebot.processor import Matcher, matchers
from nonebot.exception import NoLogException, StopPropagation, IgnoredException
from nonebot.typing import (T_State, T_RunPreProcessor, T_RunPostProcessor,
T_EventPreProcessor, T_EventPostProcessor)
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, Matcher: Type[Matcher], bot: "Bot",
event: "Event", state: T_State) -> None:
if Matcher.expire_time and datetime.now() > Matcher.expire_time:
try:
matchers[priority].remove(Matcher)
except Exception:
pass
return
try:
if not await Matcher.check_perm(
bot, event) or not await Matcher.check_rule(bot, event, state):
return
except Exception as e:
logger.opt(colors=True, exception=e).error(
f"<r><bg #f8bbd0>Rule check failed for {Matcher}.</bg #f8bbd0></r>")
return
if Matcher.temp:
try:
matchers[priority].remove(Matcher)
except Exception:
pass
await _run_matcher(Matcher, bot, event, state)
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 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:
raise StopPropagation
return
async def handle_event(bot: "Bot", event: "Event") -> None:
"""
: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>{escape_tag(bot.type.upper())} {escape_tag(bot.self_id)}</m> | "
try:
log_msg += event.get_log_string()
except NoLogException:
show_log = False
if show_log:
logger.opt(colors=True).success(log_msg)
state = {}
coros = list(map(lambda x: x(bot, event, state), _event_preprocessors))
if coros:
try:
if show_log:
logger.debug("Running PreProcessors...")
await asyncio.gather(*coros)
except IgnoredException as e:
logger.opt(colors=True).info(
f"Event {escape_tag(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}...")
pending_tasks = [
_check_matcher(priority, matcher, bot, event, state.copy())
for matcher in matchers[priority]
]
results = await asyncio.gather(*pending_tasks, return_exceptions=True)
for result in results:
if not isinstance(result, Exception):
continue
if isinstance(result, StopPropagation):
break_flag = True
logger.debug("Stop event propagation")
else:
logger.opt(colors=True, exception=result).error(
"<r><bg #f8bbd0>Error when checking Matcher.</bg #f8bbd0></r>"
)
coros = list(map(lambda x: x(bot, event, state), _event_postprocessors))
if coros:
try:
if show_log:
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>"
)