refactor: Introduce SubInfo class.

This class removes a lot of the annoying tuples
we were passing around.

Also, by including the user everywhere, which
is easily available to us when we make instances
of SubInfo, it sets the stage to remove
select_related('user_profile').

zerver/lib/actions.py

@@ -4,6 +4,7 @@ import logging
 import os
 import time
 from collections import defaultdict
+from dataclasses import dataclass
 from operator import itemgetter
 from typing import (
     AbstractSet,
@@ -232,6 +233,13 @@ from zerver.models import (
 )
 from zerver.tornado.django_api import send_event
 
+
+@dataclass
+class SubInfo:
+    user: UserProfile
+    sub: Subscription
+    stream: Stream
+
 if settings.BILLING_ENABLED:
     from corporate.lib.stripe import (
         downgrade_now_without_creating_additional_invoices,
@@ -2724,19 +2732,21 @@ def get_subscriber_emails(stream: Stream,
 
 def send_subscription_add_events(
     realm: Realm,
-    sub_streams: List[Tuple[Subscription, Stream]],
+    sub_info_list: List[SubInfo],
     subscriber_dict: Dict[int, List[int]],
 ) -> None:
-    sub_tuples_by_user: Dict[int, List[Tuple[Subscription, Stream]]] = defaultdict(list)
-    for (sub, stream) in sub_streams:
-        sub_tuples_by_user[sub.user_profile.id].append((sub, stream))
+    info_by_user: Dict[int, List[SubInfo]] = defaultdict(list)
+    for sub_info in sub_info_list:
+        info_by_user[sub_info.user.id].append(sub_info)
 
-    stream_ids = {stream.id for (sub, stream) in sub_streams}
+    stream_ids = {sub_info.stream.id for sub_info in sub_info_list}
     recent_traffic = get_streams_traffic(stream_ids=stream_ids)
 
-    for user_id, sub_streams in sub_tuples_by_user.items():
+    for user_id, sub_infos in info_by_user.items():
         sub_dicts = []
-        for (subscription, stream) in sub_streams:
+        for sub_info in sub_infos:
+            stream = sub_info.stream
+            subscription = sub_info.sub
             sub_dict = stream.to_dict()
             for field_name in Subscription.API_FIELDS:
                 if field_name == "active":
@@ -2808,7 +2818,7 @@ def get_user_ids_for_streams(streams: Iterable[Stream]) -> Dict[int, List[int]]:
 
     return all_subscribers_by_stream
 
-SubT = Tuple[List[Tuple[UserProfile, Stream]], List[Tuple[UserProfile, Stream]]]
+SubT = Tuple[List[SubInfo], List[SubInfo]]
 def bulk_add_subscriptions(
     realm: Realm,
     streams: Iterable[Stream],
@@ -2832,9 +2842,9 @@ def bulk_add_subscriptions(
     for sub in all_subs_query:
         subs_by_user[sub.user_profile_id].append(sub)
 
-    already_subscribed: List[Tuple[UserProfile, Stream]] = []
-    subs_to_activate: List[Tuple[Subscription, Stream]] = []
-    subs_to_add: List[Tuple[Subscription, Stream]] = []
+    already_subscribed: List[SubInfo] = []
+    subs_to_activate: List[SubInfo] = []
+    subs_to_add: List[SubInfo] = []
     for user_profile in users:
         my_subs = subs_by_user[user_profile.id]
         used_colors = {sub.color for sub in my_subs}
@@ -2848,10 +2858,11 @@ def bulk_add_subscriptions(
             if sub.recipient_id in new_recipient_ids:
                 new_recipient_ids.remove(sub.recipient_id)
                 stream = recipient_id_to_stream[sub.recipient_id]
+                sub_info = SubInfo(user_profile, sub, stream)
                 if sub.active:
-                    already_subscribed.append((user_profile, stream))
+                    already_subscribed.append(sub_info)
                 else:
-                    subs_to_activate.append((sub, stream))
+                    subs_to_activate.append(sub_info)
 
         for recipient_id in new_recipient_ids:
             stream = recipient_id_to_stream[recipient_id]
@@ -2862,9 +2873,14 @@ def bulk_add_subscriptions(
                 color = pick_color(user_profile, used_colors)
             used_colors.add(color)
 
-            sub_to_add = Subscription(user_profile=user_profile, active=True,
-                                      color=color, recipient_id=recipient_id)
-            subs_to_add.append((sub_to_add, stream))
+            sub = Subscription(
+                user_profile=user_profile,
+                active=True,
+                color=color,
+                recipient_id=recipient_id
+            )
+            sub_info = SubInfo(user_profile, sub, stream)
+            subs_to_add.append(sub_info)
 
     bulk_add_subs_to_db_with_logging(
         realm=realm,
@@ -2881,8 +2897,8 @@ def bulk_add_subscriptions(
     all_subscribers_by_stream = get_user_ids_for_streams(streams=streams)
 
     new_stream_user_ids: Dict[int, Set[int]] = defaultdict(set)
-    for (sub, stream) in subs_to_add + subs_to_activate:
-        new_stream_user_ids[stream.id].add(sub.user_profile_id)
+    for sub_info in subs_to_add + subs_to_activate:
+        new_stream_user_ids[sub_info.stream.id].add(sub_info.user.id)
 
     stream_dict = {stream.id: stream for stream in streams}
 
@@ -2897,7 +2913,7 @@ def bulk_add_subscriptions(
 
     send_subscription_add_events(
         realm=realm,
-        sub_streams=subs_to_add + subs_to_activate,
+        sub_info_list=subs_to_add + subs_to_activate,
         subscriber_dict=all_subscribers_by_stream,
     )
 
@@ -2908,19 +2924,20 @@ def bulk_add_subscriptions(
         all_subscribers_by_stream=all_subscribers_by_stream,
     )
 
-    return ([(sub.user_profile, stream) for (sub, stream) in subs_to_add] +
-            [(sub.user_profile, stream) for (sub, stream) in subs_to_activate],
-            already_subscribed)
+    return (
+        subs_to_add + subs_to_activate,
+        already_subscribed,
+    )
 
 def bulk_add_subs_to_db_with_logging(
     realm: Realm,
     acting_user: Optional[UserProfile],
-    subs_to_add: List[Tuple[Subscription, Stream]],
-    subs_to_activate: List[Tuple[Subscription, Stream]],
+    subs_to_add: List[SubInfo],
+    subs_to_activate: List[SubInfo],
 ) -> None:
 
-    Subscription.objects.bulk_create(sub for (sub, stream) in subs_to_add)
-    sub_ids = [sub.id for (sub, stream) in subs_to_activate]
+    Subscription.objects.bulk_create(info.sub for info in subs_to_add)
+    sub_ids = [info.sub.id for info in subs_to_activate]
     Subscription.objects.filter(id__in=sub_ids).update(active=True)
 
     # Log Subscription Activities in RealmAuditLog
@@ -2928,19 +2945,19 @@ def bulk_add_subs_to_db_with_logging(
     event_last_message_id = get_last_message_id()
 
     all_subscription_logs: (List[RealmAuditLog]) = []
-    for (sub, stream) in subs_to_add:
+    for sub_info in subs_to_add:
         all_subscription_logs.append(RealmAuditLog(realm=realm,
                                                    acting_user=acting_user,
-                                                   modified_user=sub.user_profile,
-                                                   modified_stream=stream,
+                                                   modified_user=sub_info.user,
+                                                   modified_stream=sub_info.stream,
                                                    event_last_message_id=event_last_message_id,
                                                    event_type=RealmAuditLog.SUBSCRIPTION_CREATED,
                                                    event_time=event_time))
-    for (sub, stream) in subs_to_activate:
+    for sub_info in subs_to_activate:
         all_subscription_logs.append(RealmAuditLog(realm=realm,
                                                    acting_user=acting_user,
-                                                   modified_user=sub.user_profile,
-                                                   modified_stream=stream,
+                                                   modified_user=sub_info.user,
+                                                   modified_stream=sub_info.stream,
                                                    event_last_message_id=event_last_message_id,
                                                    event_type=RealmAuditLog.SUBSCRIPTION_ACTIVATED,
                                                    event_time=event_time))

zerver/management/commands/add_users_to_streams.py

@@ -29,7 +29,7 @@ class Command(ZulipBaseCommand):
             for user_profile in user_profiles:
                 stream = ensure_stream(realm, stream_name, acting_user=None)
                 _ignore, already_subscribed = bulk_add_subscriptions(realm, [stream], [user_profile])
-                was_there_already = user_profile.id in (tup[0].id for tup in already_subscribed)
+                was_there_already = user_profile.id in (info.user.id for info in already_subscribed)
                 print("{} {} to {}".format(
                     "Already subscribed" if was_there_already else "Subscribed",
                     user_profile.delivery_email, stream_name))

zerver/views/streams.py

@@ -489,10 +489,14 @@ def add_subscriptions_backend(
     email_to_user_profile: Dict[str, UserProfile] = {}
 
     result: Dict[str, Any] = dict(subscribed=defaultdict(list), already_subscribed=defaultdict(list))
-    for (subscriber, stream) in subscribed:
+    for sub_info in subscribed:
+        subscriber = sub_info.user
+        stream = sub_info.stream
         result["subscribed"][subscriber.email].append(stream.name)
         email_to_user_profile[subscriber.email] = subscriber
-    for (subscriber, stream) in already_subscribed:
+    for sub_info in already_subscribed:
+        subscriber = sub_info.user
+        stream = sub_info.stream
         result["already_subscribed"][subscriber.email].append(stream.name)
 
     result["subscribed"] = dict(result["subscribed"])