search: Add server support for has:reaction search operator.

Web app support will be a follow-up commit.

api_docs/changelog.md

@@ -20,6 +20,13 @@ format used by the Zulip server that they are interacting with.
 
 ## Changes in Zulip 9.0
 
+**Feature level 249**
+
+* [`GET /messages`](/api/get-messages), [`GET
+  /messages/matches_narrow`](/api/check-messages-match-narrow): Added
+  new `has:reaction` search operator, matching messages with at least
+  one emoji reaction.
+
 **Feature level 248**
 
 * [`POST /typing`](/api/set-typing-status), [`POST /messages`](/api/send-message),

api_docs/construct-narrow.md

@@ -51,7 +51,11 @@ important optimization when fetching messages in certain cases (e.g.
 when [adding the `read` flag to a user's personal
 messages](/api/update-message-flags-for-narrow)).
 
-**Changes**: In Zulip 7.0 (feature level 177), support was added
+**Changes**: In Zulip 9.0 (feature level 249), narrows gained support
+for a new filter `has:reaction`. This allows clients to retrieve only
+messages that have at least one reaction.
+
+In Zulip 7.0 (feature level 177), support was added
 for three filters related to direct messages: `is:dm`, `dm` and
 `dm-including`. The `dm` operator replaced and deprecated the
 `pm-with` operator. The `is:dm` filter replaced and deprecated

version.py

@@ -33,7 +33,7 @@ DESKTOP_WARNING_VERSION = "5.9.3"
 # Changes should be accompanied by documentation explaining what the
 # new level means in api_docs/changelog.md, as well as "**Changes**"
 # entries in the endpoint's documentation in `zulip.yaml`.
-API_FEATURE_LEVEL = 248
+API_FEATURE_LEVEL = 249
 
 # Bump the minor PROVISION_VERSION to indicate that folks should provision
 # only when going from an old version of the code to a newer version. Bump

zerver/lib/narrow.py

@@ -333,8 +333,24 @@ class NarrowBuilder:
         return method(query, operand, maybe_negate)
 
     def by_has(self, query: Select, operand: str, maybe_negate: ConditionTransform) -> Select:
-        if operand not in ["attachment", "image", "link"]:
+        if operand not in ["attachment", "image", "link", "reaction"]:
             raise BadNarrowOperatorError("unknown 'has' operand " + operand)
+
+        if operand == "reaction":
+            if self.msg_id_column.name == "message_id":
+                # If the initial query uses `zerver_usermessage`
+                check_col = literal_column("zerver_usermessage.message_id", Integer)
+            else:
+                # If the initial query doesn't use `zerver_usermessage`
+                check_col = literal_column("zerver_message.id", Integer)
+            exists_cond = (
+                select([1])
+                .select_from(table("zerver_reaction"))
+                .where(check_col == literal_column("zerver_reaction.message_id", Integer))
+                .exists()
+            )
+            return query.where(maybe_negate(exists_cond))
+
         col_name = "has_" + operand
         cond = column(col_name, Boolean)
         return query.where(maybe_negate(cond))

zerver/openapi/zulip.yaml

@@ -6189,7 +6189,10 @@ paths:
             subscribed to appropriate streams or use a shared history
             search narrow with this endpoint.
 
-            **Changes**: In Zulip 7.0 (feature level 177), narrows gained support
+            **Changes**: In Zulip 9.0 (feature level 249), added new `has:reaction`
+            filter, matching messages with at least one emoji reaction.
+
+            In Zulip 7.0 (feature level 177), narrows gained support
             for three new filters related to direct messages: `is:dm`, `dm` and
             `dm-including`; replacing and deprecating `is:private`, `pm-with` and
             `group-pm-with` respectively.
@@ -7059,7 +7062,10 @@ paths:
                     optimization. Including that filter takes advantage of the fact that
                     the server has a database index for unread messages.
 
-                    **Changes**: In Zulip 7.0 (feature level 177), narrows gained support
+                    **Changes**: In Zulip 9.0 (feature level 249), added new `has:reaction`
+                    filter, matching messages with at least one emoji reaction.
+
+                    In Zulip 7.0 (feature level 177), narrows gained support
                     for three new filters related to direct messages: `is:dm`, `dm` and
                     `dm-including`; replacing and deprecating `is:private`, `pm-with` and
                     `group-pm-with` respectively.
@@ -7483,7 +7489,10 @@ paths:
             A structure defining the narrow to check against. See how to
             [construct a narrow](/api/construct-narrow).
 
-            **Changes**: In Zulip 7.0 (feature level 177), narrows gained support
+            **Changes**: In Zulip 9.0 (feature level 249), added new `has:reaction`
+            filter, matching messages with at least one emoji reaction.
+
+            In Zulip 7.0 (feature level 177), narrows gained support
             for three new filters related to direct messages: `is:dm`, `dm` and
             `dm-including`; replacing and deprecating `is:private`, `pm-with` and
             `group-pm-with` respectively.
@@ -21361,7 +21370,10 @@ components:
 
         Defaults to `[]`.
 
-        **Changes**: In Zulip 7.0 (feature level 177), narrows gained support
+        **Changes**: In Zulip 9.0 (feature level 249), added new `has:reaction`
+        filter, matching messages with at least one emoji reaction.
+
+        In Zulip 7.0 (feature level 177), narrows gained support
         for three new filters related to direct messages: `is:dm`, `dm` and
         `dm-including`; replacing and deprecating `is:private`, `pm-with` and
         `group-pm-with` respectively.

zerver/tests/test_message_fetch.py

@@ -13,6 +13,7 @@ from typing_extensions import override
 from analytics.lib.counts import COUNT_STATS
 from analytics.models import RealmCount
 from zerver.actions.message_edit import do_update_message
+from zerver.actions.reactions import check_add_reaction
 from zerver.actions.realm_settings import do_set_realm_property
 from zerver.actions.uploads import do_claim_attachments
 from zerver.actions.user_settings import do_change_user_setting
@@ -491,6 +492,20 @@ class NarrowBuilderTest(ZulipTestCase):
         term = dict(operator="has", operand="link", negated=True)
         self._do_add_term_test(term, "WHERE NOT has_link")
 
+    def test_add_term_using_has_operator_and_reaction_operand(self) -> None:
+        term = dict(operator="has", operand="reaction")
+        self._do_add_term_test(
+            term,
+            "EXISTS (SELECT 1 \nFROM zerver_reaction \nWHERE zerver_message.id = zerver_reaction.message_id)",
+        )
+
+    def test_add_term_using_has_operator_and_reaction_operand_and_negated(self) -> None:
+        term = dict(operator="has", operand="reaction", negated=True)
+        self._do_add_term_test(
+            term,
+            "NOT (EXISTS (SELECT 1 \nFROM zerver_reaction \nWHERE zerver_message.id = zerver_reaction.message_id))",
+        )
+
     def test_add_term_using_has_operator_non_supported_operand_should_raise_error(self) -> None:
         term = dict(operator="has", operand="non_supported")
         self.assertRaises(BadNarrowOperatorError, self._build_query, term)
@@ -4422,6 +4437,44 @@ class MessageHasKeywordsTest(ZulipTestCase):
             self.assertFalse(m.called)
             m.reset_mock()
 
+    def test_has_reaction(self) -> None:
+        self.login("iago")
+        has_reaction_narrow = orjson.dumps([dict(operator="has", operand="reaction")]).decode()
+
+        msg_id = self.send_stream_message(self.example_user("hamlet"), "Denmark", content="Hey")
+        result = self.client_get(
+            "/json/messages",
+            dict(narrow=has_reaction_narrow, anchor=msg_id, num_before=0, num_after=0),
+        )
+        messages = self.assert_json_success(result)["messages"]
+        self.assert_length(messages, 0)
+        check_add_reaction(
+            self.example_user("hamlet"), msg_id, "hamburger", "1f354", "unicode_emoji"
+        )
+        result = self.client_get(
+            "/json/messages",
+            dict(narrow=has_reaction_narrow, anchor=msg_id, num_before=0, num_after=0),
+        )
+        messages = self.assert_json_success(result)["messages"]
+        self.assert_length(messages, 1)
+
+        msg_id = self.send_personal_message(
+            self.example_user("iago"), self.example_user("cordelia"), "Hello Cordelia"
+        )
+        result = self.client_get(
+            "/json/messages",
+            dict(narrow=has_reaction_narrow, anchor=msg_id, num_before=0, num_after=0),
+        )
+        messages = self.assert_json_success(result)["messages"]
+        self.assert_length(messages, 0)
+        check_add_reaction(self.example_user("iago"), msg_id, "hamburger", "1f354", "unicode_emoji")
+        result = self.client_get(
+            "/json/messages",
+            dict(narrow=has_reaction_narrow, anchor=msg_id, num_before=0, num_after=0),
+        )
+        messages = self.assert_json_success(result)["messages"]
+        self.assert_length(messages, 1)
+
 
 class MessageVisibilityTest(ZulipTestCase):
     def test_update_first_visible_message_id(self) -> None: