refactor: Add MentionBackend.

We will eventually use this to avoid redundant
queries.

The diff is slightly noisy here, but there are no
logic changes.

zerver/lib/actions.py

@@ -100,7 +100,7 @@ from zerver.lib.hotspots import get_next_hotspots
 from zerver.lib.i18n import get_language_name
 from zerver.lib.markdown import MessageRenderingResult, topic_links
 from zerver.lib.markdown import version as markdown_version
-from zerver.lib.mention import MentionData, silent_mention_syntax_for_user
+from zerver.lib.mention import MentionBackend, MentionData, silent_mention_syntax_for_user
 from zerver.lib.message import (
     MessageDict,
     SendMessageRequest,
@@ -1863,8 +1863,9 @@ def build_message_send_dict(
     if realm is None:
         realm = message.sender.realm
 
+    mention_backend = MentionBackend(realm.id)
     mention_data = MentionData(
-        realm_id=realm.id,
+        mention_backend=mention_backend,
         content=message.content,
     )
 
@@ -3065,8 +3066,9 @@ def check_update_message(
             content = "(deleted)"
         content = normalize_body(content)
 
+        mention_backend = MentionBackend(user_profile.realm_id)
         mention_data = MentionData(
-            realm_id=user_profile.realm.id,
+            mention_backend=mention_backend,
             content=content,
         )
         user_info = get_user_info_for_message_updates(message.id)

zerver/lib/markdown/__init__.py

@@ -54,7 +54,7 @@ from zerver.lib.emoji import EMOTICON_RE, codepoint_to_name, name_to_codepoint,
 from zerver.lib.exceptions import MarkdownRenderingException
 from zerver.lib.markdown import fenced_code
 from zerver.lib.markdown.fenced_code import FENCE_RE
-from zerver.lib.mention import FullNameInfo, MentionData, get_stream_name_map
+from zerver.lib.mention import FullNameInfo, MentionBackend, MentionData, get_stream_name_map
 from zerver.lib.outgoing_http import OutgoingSession
 from zerver.lib.subdomains import is_static_or_current_realm_url
 from zerver.lib.tex import render_tex
@@ -2508,7 +2508,8 @@ def do_convert(
         # are uncommon enough that it's a useful optimization.
 
         if mention_data is None:
-            mention_data = MentionData(message_realm.id, content)
+            mention_backend = MentionBackend(message_realm.id)
+            mention_data = MentionData(mention_backend, content)
 
         stream_names = possible_linked_stream_names(content)
         stream_name_info = get_stream_name_map(message_realm, stream_names)

zerver/lib/mention.py

@@ -37,6 +37,29 @@ class UserFilter:
             raise AssertionError("totally empty filter makes no sense")
 
 
+@dataclass
+class MentionBackend:
+    realm_id: int
+
+    def get_full_name_info_list(self, user_filters: List[UserFilter]) -> List[FullNameInfo]:
+        q_list = [user_filter.Q() for user_filter in user_filters]
+
+        rows = (
+            UserProfile.objects.filter(
+                realm_id=self.realm_id,
+                is_active=True,
+            )
+            .filter(
+                functools.reduce(lambda a, b: a | b, q_list),
+            )
+            .only(
+                "id",
+                "full_name",
+            )
+        )
+        return [FullNameInfo(id=row.id, full_name=row.full_name) for row in rows]
+
+
 def user_mention_matches_wildcard(mention: str) -> bool:
     return mention in wildcards
 
@@ -65,7 +88,9 @@ def possible_user_group_mentions(content: str) -> Set[str]:
     return {m.group("match") for m in USER_GROUP_MENTIONS_RE.finditer(content)}
 
 
-def get_possible_mentions_info(realm_id: int, mention_texts: Set[str]) -> List[FullNameInfo]:
+def get_possible_mentions_info(
+    mention_backend: MentionBackend, mention_texts: Set[str]
+) -> List[FullNameInfo]:
     if not mention_texts:
         return []
 
@@ -88,28 +113,14 @@ def get_possible_mentions_info(realm_id: int, mention_texts: Set[str]) -> List[F
             # For **name** syntax.
             user_filters.append(UserFilter(full_name=mention_text, id=None))
 
-    q_list = [user_filter.Q() for user_filter in user_filters]
+    return mention_backend.get_full_name_info_list(user_filters)
-
-    rows = (
-        UserProfile.objects.filter(
-            realm_id=realm_id,
-            is_active=True,
-        )
-        .filter(
-            functools.reduce(lambda a, b: a | b, q_list),
-        )
-        .only(
-            "id",
-            "full_name",
-        )
-    )
-    return [FullNameInfo(id=row.id, full_name=row.full_name) for row in rows]
 
 
 class MentionData:
-    def __init__(self, realm_id: int, content: str) -> None:
+    def __init__(self, mention_backend: MentionBackend, content: str) -> None:
+        realm_id = mention_backend.realm_id
         mention_texts, has_wildcards = possible_mentions(content)
-        possible_mentions_info = get_possible_mentions_info(realm_id, mention_texts)
+        possible_mentions_info = get_possible_mentions_info(mention_backend, mention_texts)
         self.full_name_info = {row.full_name.lower(): row for row in possible_mentions_info}
         self.user_id_info = {row.id: row for row in possible_mentions_info}
         self.init_user_group_data(realm_id=realm_id, content=content)

zerver/tests/test_events.py

@@ -171,7 +171,7 @@ from zerver.lib.events import (
     fetch_initial_state_data,
     post_process_state,
 )
-from zerver.lib.mention import MentionData
+from zerver.lib.mention import MentionBackend, MentionData
 from zerver.lib.message import render_markdown
 from zerver.lib.test_classes import ZulipTestCase
 from zerver.lib.test_helpers import (
@@ -437,8 +437,9 @@ class NormalActionsTest(BaseAction):
         content = "new content"
         rendering_result = render_markdown(pm, content)
         prior_mention_user_ids: Set[int] = set()
+        mention_backend = MentionBackend(self.user_profile.realm_id)
         mention_data = MentionData(
-            realm_id=self.user_profile.realm_id,
+            mention_backend=mention_backend,
             content=content,
         )
 
@@ -496,8 +497,9 @@ class NormalActionsTest(BaseAction):
         content = "new content"
         rendering_result = render_markdown(message, content)
         prior_mention_user_ids: Set[int] = set()
+        mention_backend = MentionBackend(self.user_profile.realm_id)
         mention_data = MentionData(
-            realm_id=self.user_profile.realm_id,
+            mention_backend=mention_backend,
             content=content,
         )
 

zerver/tests/test_markdown.py

@@ -42,6 +42,7 @@ from zerver.lib.markdown.fenced_code import FencedBlockPreprocessor
 from zerver.lib.mdiff import diff_strings
 from zerver.lib.mention import (
     FullNameInfo,
+    MentionBackend,
     MentionData,
     get_possible_mentions_info,
     possible_mentions,
@@ -232,8 +233,9 @@ class MarkdownMiscTest(ZulipTestCase):
 
         fred4 = make_user("fred4@example.com", "Fred Flintstone")
 
+        mention_backend = MentionBackend(realm.id)
         lst = get_possible_mentions_info(
-            realm.id, {"Fred Flintstone", "Cordelia, LEAR's daughter", "Not A User"}
+            mention_backend, {"Fred Flintstone", "Cordelia, LEAR's daughter", "Not A User"}
         )
         set_of_names = set(map(lambda x: x.full_name.lower(), lst))
         self.assertEqual(set_of_names, {"fred flintstone", "cordelia, lear's daughter"})
@@ -259,7 +261,8 @@ class MarkdownMiscTest(ZulipTestCase):
         hamlet = self.example_user("hamlet")
         cordelia = self.example_user("cordelia")
         content = "@**King Hamlet** @**Cordelia, lear's daughter**"
-        mention_data = MentionData(realm.id, content)
+        mention_backend = MentionBackend(realm.id)
+        mention_data = MentionData(mention_backend, content)
         self.assertEqual(mention_data.get_user_ids(), {hamlet.id, cordelia.id})
         self.assertEqual(
             mention_data.get_user_by_id(hamlet.id),
@@ -275,7 +278,7 @@ class MarkdownMiscTest(ZulipTestCase):
 
         self.assertFalse(mention_data.message_has_wildcards())
         content = "@**King Hamlet** @**Cordelia, lear's daughter** @**all**"
-        mention_data = MentionData(realm.id, content)
+        mention_data = MentionData(mention_backend, content)
         self.assertTrue(mention_data.message_has_wildcards())
 
     def test_invalid_katex_path(self) -> None:

zerver/tests/test_message_fetch.py

@@ -21,7 +21,7 @@ from zerver.lib.actions import (
 )
 from zerver.lib.avatar import avatar_url
 from zerver.lib.exceptions import JsonableError
-from zerver.lib.mention import MentionData
+from zerver.lib.mention import MentionBackend, MentionData
 from zerver.lib.message import (
     MessageDict,
     get_first_visible_message_id,
@@ -3776,7 +3776,8 @@ class MessageHasKeywordsTest(ZulipTestCase):
         hamlet = self.example_user("hamlet")
         realm_id = hamlet.realm.id
         rendering_result = render_markdown(msg, content)
-        mention_data = MentionData(realm_id, content)
+        mention_backend = MentionBackend(realm_id)
+        mention_data = MentionData(mention_backend, content)
         do_update_message(
             hamlet,
             msg,

zerver/tests/test_notification_data.py

@@ -1,4 +1,4 @@
-from zerver.lib.mention import MentionData
+from zerver.lib.mention import MentionBackend, MentionData
 from zerver.lib.notification_data import get_user_group_mentions_data
 from zerver.lib.test_classes import ZulipTestCase
 from zerver.lib.user_groups import create_user_group
@@ -220,11 +220,13 @@ class TestNotificationData(ZulipTestCase):
         hamlet_only = create_user_group("hamlet_only", [hamlet], realm)
         hamlet_and_cordelia = create_user_group("hamlet_and_cordelia", [hamlet, cordelia], realm)
 
+        mention_backend = MentionBackend(realm.id)
+
         # Base case. No user/user group mentions
         result = get_user_group_mentions_data(
             mentioned_user_ids=set(),
             mentioned_user_group_ids=[],
-            mention_data=MentionData(realm.id, "no group mentioned"),
+            mention_data=MentionData(mention_backend, "no group mentioned"),
         )
         self.assertDictEqual(result, {})
 
@@ -232,7 +234,7 @@ class TestNotificationData(ZulipTestCase):
         result = get_user_group_mentions_data(
             mentioned_user_ids=set(),
             mentioned_user_group_ids=[hamlet_and_cordelia.id],
-            mention_data=MentionData(realm.id, "hey @*hamlet_and_cordelia*!"),
+            mention_data=MentionData(mention_backend, "hey @*hamlet_and_cordelia*!"),
         )
         self.assertDictEqual(
             result,
@@ -247,7 +249,9 @@ class TestNotificationData(ZulipTestCase):
         result = get_user_group_mentions_data(
             mentioned_user_ids=set(),
             mentioned_user_group_ids=[hamlet_and_cordelia.id, hamlet_only.id],
-            mention_data=MentionData(realm.id, "hey @*hamlet_and_cordelia* and @*hamlet_only*"),
+            mention_data=MentionData(
+                mention_backend, "hey @*hamlet_and_cordelia* and @*hamlet_only*"
+            ),
         )
         self.assertDictEqual(
             result,
@@ -262,7 +266,9 @@ class TestNotificationData(ZulipTestCase):
         result = get_user_group_mentions_data(
             mentioned_user_ids=set(),
             mentioned_user_group_ids=[hamlet_only.id, hamlet_and_cordelia.id],
-            mention_data=MentionData(realm.id, "hey @*hamlet_only* and @*hamlet_and_cordelia*"),
+            mention_data=MentionData(
+                mention_backend, "hey @*hamlet_only* and @*hamlet_and_cordelia*"
+            ),
         )
         self.assertDictEqual(
             result,
@@ -277,7 +283,7 @@ class TestNotificationData(ZulipTestCase):
         result = get_user_group_mentions_data(
             mentioned_user_ids={hamlet.id},
             mentioned_user_group_ids=[hamlet_and_cordelia.id],
-            mention_data=MentionData(realm.id, "hey @*hamlet_and_cordelia*!"),
+            mention_data=MentionData(mention_backend, "hey @*hamlet_and_cordelia*!"),
         )
         self.assertDictEqual(
             result,