From f22d602a10cbbf64e7adf79cb3d814070c27c5c6 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C4=B0smail=20Karsl=C4=B1?= <cszn@pm.me>
Date: Wed, 15 Nov 2023 23:55:00 +0300
Subject: [PATCH] Add local_subscribers field to CommunityAggregates struct and
 schema

---
 crates/db_schema/src/aggregates/structs.rs    |  1 +
 crates/db_schema/src/schema.rs                |  1 +
 .../down.sql                                  | 35 +++++++++++
 .../up.sql                                    | 61 +++++++++++++++++++
 4 files changed, 98 insertions(+)
 create mode 100644 migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/down.sql
 create mode 100644 migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/up.sql

diff --git a/crates/db_schema/src/aggregates/structs.rs b/crates/db_schema/src/aggregates/structs.rs
index 24b2d82c5..7629cb0e2 100644
--- a/crates/db_schema/src/aggregates/structs.rs
+++ b/crates/db_schema/src/aggregates/structs.rs
@@ -59,6 +59,7 @@ pub struct CommunityAggregates {
   pub users_active_half_year: i64,
   #[serde(skip)]
   pub hot_rank: f64,
+  pub local_subscribers: i64,
 }
 
 #[derive(PartialEq, Eq, Debug, Serialize, Deserialize, Clone, Default)]
diff --git a/crates/db_schema/src/schema.rs b/crates/db_schema/src/schema.rs
index 88d468a6f..a89c00619 100644
--- a/crates/db_schema/src/schema.rs
+++ b/crates/db_schema/src/schema.rs
@@ -198,6 +198,7 @@ diesel::table! {
         users_active_month -> Int8,
         users_active_half_year -> Int8,
         hot_rank -> Float8,
+        local_subscribers -> Int8,
     }
 }
 
diff --git a/migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/down.sql b/migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/down.sql
new file mode 100644
index 000000000..6dd941011
--- /dev/null
+++ b/migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/down.sql
@@ -0,0 +1,35 @@
+ALTER TABLE community_aggregates
+		DROP COLUMN local_subscribers;
+
+CREATE OR REPLACE FUNCTION community_aggregates_subscriber_count ()
+    RETURNS TRIGGER
+    LANGUAGE plpgsql
+    AS $$
+BEGIN
+    IF (TG_OP = 'INSERT') THEN
+        UPDATE
+            community_aggregates
+        SET
+            subscribers = subscribers + 1
+        FROM
+            community
+        WHERE
+            community.id = community_id
+            AND community.local
+            AND community_id = NEW.community_id;
+    ELSIF (TG_OP = 'DELETE') THEN
+        UPDATE
+            community_aggregates
+        SET
+            subscribers = subscribers - 1
+        FROM
+            community
+        WHERE
+            community.id = community_id
+            AND community.local
+            AND community_id = OLD.community_id;
+    END IF;
+    RETURN NULL;
+END
+$$;
+
diff --git a/migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/up.sql b/migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/up.sql
new file mode 100644
index 000000000..226b39fec
--- /dev/null
+++ b/migrations/2023-11-15-200123_community_aggregates_add_local_subscribers/up.sql
@@ -0,0 +1,61 @@
+-- Couldn't find a way to put local_subscribers right after subscribers
+ALTER TABLE community_aggregates
+    ADD COLUMN local_subscribers int8 NOT NULL DEFAULT 0;
+
+-- update initial value
+UPDATE
+    community_aggregates
+SET
+    local_subscribers = (
+        SELECT
+            COUNT(*)
+        FROM
+            community_follower
+        WHERE
+            community_follower.community_id = community_aggregates.community_id
+            AND community_follower.person_id IN (
+                SELECT
+                    id
+                FROM
+                    person
+                WHERE
+                    local
+            )
+    )
+;
+
+
+CREATE OR REPLACE FUNCTION community_aggregates_subscriber_count ()
+    RETURNS TRIGGER
+    LANGUAGE plpgsql
+    AS $$
+BEGIN
+    IF (TG_OP = 'INSERT') THEN
+        UPDATE
+            community_aggregates
+        SET
+            subscribers = subscribers + 1,
+            local_subscribers = local_subscribers + 1
+        FROM
+            community
+        WHERE
+            community.id = community_id
+            AND community.local
+            AND community_id = NEW.community_id;
+    ELSIF (TG_OP = 'DELETE') THEN
+        UPDATE
+            community_aggregates
+        SET
+            subscribers = subscribers - 1,
+            local_subscribers = local_subscribers - 1
+        FROM
+            community
+        WHERE
+            community.id = community_id
+            AND community.local
+            AND community_id = OLD.community_id;
+    END IF;
+    RETURN NULL;
+END
+$$;
+