Merge branch 'bug/1142/fix-everyone-ping' into master

6 files changed, 47 insertions, 62 deletions

diff --git a/bot/constants.py b/bot/constants.py
index 17f14fec0..e4e0b1732 100644
--- a/bot/constants.py
+++ b/bot/constants.py
@@ -217,6 +217,7 @@ class Filter(metaclass=YAMLGetter):
     filter_zalgo: bool
     filter_invites: bool
     filter_domains: bool
+    filter_everyone_ping: bool
     watch_regex: bool
     watch_rich_embeds: bool
 
@@ -224,6 +225,7 @@ class Filter(metaclass=YAMLGetter):
     notify_user_zalgo: bool
     notify_user_invites: bool
     notify_user_domains: bool
+    notify_user_everyone_ping: bool
 
     ping_everyone: bool
     offensive_msg_delete_days: int
diff --git a/bot/exts/filters/antispam.py b/bot/exts/filters/antispam.py
index 2e7e32d9a..f2a2689e1 100644
--- a/bot/exts/filters/antispam.py
+++ b/bot/exts/filters/antispam.py
@@ -36,9 +36,6 @@ RULE_FUNCTION_MAPPING = {
     'mentions': rules.apply_mentions,
     'newlines': rules.apply_newlines,
     'role_mentions': rules.apply_role_mentions,
-    # the everyone filter is temporarily disabled until
-    # it has been improved.
-    # 'everyone_ping': rules.apply_everyone_ping,
 }
 
 
diff --git a/bot/exts/filters/filtering.py b/bot/exts/filters/filtering.py
index 2751ed7f6..3bf0d88a0 100644
--- a/bot/exts/filters/filtering.py
+++ b/bot/exts/filters/filtering.py
@@ -14,8 +14,8 @@ from discord.utils import escape_markdown
 from bot.api import ResponseCodeError
 from bot.bot import Bot
 from bot.constants import (
-    Channels, Colours,
-    Filter, Icons, URLs
+    Channels, Colours, Filter,
+    Guild, Icons, URLs
 )
 from bot.exts.moderation.modlog import ModLog
 from bot.utils.redis_cache import RedisCache
@@ -25,6 +25,12 @@ from bot.utils.scheduling import Scheduler
 log = logging.getLogger(__name__)
 
 # Regular expressions
+CODE_BLOCK_RE = re.compile(
+    r"(?P<delim>``?)[^`]+?(?P=delim)(?!`+)"  # Inline codeblock
+    r"|```(.+?)```",  # Multiline codeblock
+    re.DOTALL | re.MULTILINE
+)
+EVERYONE_PING_RE = re.compile(rf"@everyone|<@&{Guild.id}>|@here")
 SPOILER_RE = re.compile(r"(\|\|.+?\|\|)", re.DOTALL)
 URL_RE = re.compile(r"(https?://[^\s]+)", flags=re.IGNORECASE)
 ZALGO_RE = re.compile(r"[\u0300-\u036F\u0489]")
@@ -82,6 +88,19 @@ class Filtering(Cog):
                 ),
                 "schedule_deletion": False
             },
+            "filter_everyone_ping": {
+                "enabled": Filter.filter_everyone_ping,
+                "function": self._has_everyone_ping,
+                "type": "filter",
+                "content_only": True,
+                "user_notification": Filter.notify_user_everyone_ping,
+                "notification_msg": (
+                    "Please don't try to ping `@everyone` or `@here`. "
+                    f"Your message has been removed. {staff_mistake_str}"
+                ),
+                "schedule_deletion": False,
+                "ping_everyone": False
+            },
             "watch_regex": {
                 "enabled": Filter.watch_regex,
                 "function": self._has_watch_regex_match,
@@ -332,6 +351,9 @@ class Filtering(Cog):
 
                         log.debug(message)
 
+                        # Allow specific filters to override ping_everyone
+                        ping_everyone = Filter.ping_everyone and _filter.get("ping_everyone", True)
+
                         # Send pretty mod log embed to mod-alerts
                         await self.mod_log.send_log_message(
                             icon_url=Icons.filtering,
@@ -340,7 +362,7 @@ class Filtering(Cog):
                             text=message,
                             thumbnail=msg.author.avatar_url_as(static_format="png"),
                             channel_id=Channels.mod_alerts,
-                            ping_everyone=Filter.ping_everyone if not is_private else False,
+                            ping_everyone=ping_everyone if not is_private else False,
                             additional_embeds=additional_embeds,
                             additional_embeds_msg=additional_embeds_msg
                         )
@@ -528,6 +550,16 @@ class Filtering(Cog):
                         return False
         return False
 
+    @staticmethod
+    async def _has_everyone_ping(text: str) -> bool:
+        """Determines if `msg` contains an @everyone or @here ping outside of a codeblock."""
+        # First pass to avoid running re.sub on every message
+        if not EVERYONE_PING_RE.search(text):
+            return False
+
+        content_without_codeblocks = CODE_BLOCK_RE.sub("", text)
+        return bool(EVERYONE_PING_RE.search(content_without_codeblocks))
+
     async def notify_member(self, filtered_member: Member, reason: str, channel: TextChannel) -> None:
         """
         Notify filtered_member about a moderation action with the reason str.
diff --git a/bot/rules/__init__.py b/bot/rules/__init__.py
index 8a69cadee..a01ceae73 100644
--- a/bot/rules/__init__.py
+++ b/bot/rules/__init__.py
@@ -10,4 +10,3 @@ from .links import apply as apply_links
 from .mentions import apply as apply_mentions
 from .newlines import apply as apply_newlines
 from .role_mentions import apply as apply_role_mentions
-from .everyone_ping import apply as apply_everyone_ping
diff --git a/bot/rules/everyone_ping.py b/bot/rules/everyone_ping.py
deleted file mode 100644
index 89d9fe570..000000000
--- a/bot/rules/everyone_ping.py
+++ /dev/null
@@ -1,41 +0,0 @@
-import random
-import re
-from typing import Dict, Iterable, List, Optional, Tuple
-
-from discord import Embed, Member, Message
-
-from bot.constants import Colours, Guild, NEGATIVE_REPLIES
-
-# Generate regex for checking for pings:
-guild_id = Guild.id
-EVERYONE_RE_INLINE_CODE = re.compile(rf"^(?!`).*@everyone.*(?!`)$|^(?!`).*<@&{guild_id}>.*(?!`)$")
-EVERYONE_RE_MULTILINE_CODE = re.compile(rf"^(?!```).*@everyone.*(?!```)$|^(?!```).*<@&{guild_id}>.*(?!```)$")
-
-
-async def apply(
-    last_message: Message,
-    recent_messages: List[Message],
-    config: Dict[str, int],
-) -> Optional[Tuple[str, Iterable[Member], Iterable[Message]]]:
-    """Detects if a user has sent an '@everyone' ping."""
-    relevant_messages = tuple(msg for msg in recent_messages if msg.author == last_message.author)
-
-    everyone_messages_count = 0
-    for msg in relevant_messages:
-        num_everyone_pings_inline = len(re.findall(EVERYONE_RE_INLINE_CODE, msg.content))
-        num_everyone_pings_multiline = len(re.findall(EVERYONE_RE_MULTILINE_CODE, msg.content))
-        if num_everyone_pings_inline and num_everyone_pings_multiline:
-            everyone_messages_count += 1
-
-    if everyone_messages_count > config["max"]:
-        # Send the channel an embed giving the user more info:
-        embed_text = f"Please don't try to ping {last_message.guild.member_count:,} people."
-        embed = Embed(title=random.choice(NEGATIVE_REPLIES), description=embed_text, colour=Colours.soft_red)
-        await last_message.channel.send(embed=embed)
-
-        return (
-            "pinged the everyone role",
-            (last_message.author,),
-            relevant_messages,
-        )
-    return None
diff --git a/config-default.yml b/config-default.yml
index 58651f548..465f61b5f 100644
--- a/config-default.yml
+++ b/config-default.yml
@@ -275,17 +275,19 @@ guild:
 
 filter:
     # What do we filter?
-    filter_zalgo:       false
-    filter_invites:     true
-    filter_domains:     true
-    watch_regex:        true
-    watch_rich_embeds:  true
+    filter_zalgo:          false
+    filter_invites:        true
+    filter_domains:        true
+    filter_everyone_ping:  true
+    watch_regex:           true
+    watch_rich_embeds:     true
 
     # Notify user on filter?
     # Notifications are not expected for "watchlist" type filters
-    notify_user_zalgo:       false
-    notify_user_invites:     true
-    notify_user_domains:     false
+    notify_user_zalgo:          false
+    notify_user_invites:        true
+    notify_user_domains:        false
+    notify_user_everyone_ping:  true
 
     # Filter configuration
     ping_everyone:             true
@@ -391,12 +393,6 @@ anti_spam:
             interval: 10
             max: 3
 
-        # The everyone ping filter is temporarily disabled
-        # until we've fixed a couple of bugs.
-        # everyone_ping:
-        #    interval: 10
-        #    max: 0
-
 
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