From 9114c8cb8e7d0bb0f686190d47c60591ac211f35 Mon Sep 17 00:00:00 2001
From: syuilo <Syuilotan@yahoo.co.jp>
Date: Sat, 8 Apr 2023 15:53:36 +0900
Subject: [PATCH] feat(backend): support replication of postgresql

Resolve #10205
---
 .config/docker_example.yml       | 17 +++++++++++++++++
 .config/example.yml              | 17 +++++++++++++++++
 .devcontainer/devcontainer.yml   | 17 +++++++++++++++++
 CHANGELOG.md                     |  2 ++
 chart/files/default.yml          | 17 +++++++++++++++++
 packages/backend/src/config.ts   | 10 ++++++++++
 packages/backend/src/postgres.ts | 16 ++++++++++++++++
 7 files changed, 96 insertions(+)

diff --git a/.config/docker_example.yml b/.config/docker_example.yml
index d93cc8b70e..af0a90dc95 100644
--- a/.config/docker_example.yml
+++ b/.config/docker_example.yml
@@ -51,6 +51,23 @@ db:
   #extra:
   #  ssl: true
 
+dbReplications: false
+
+# You can configure any number of replicas here
+#dbSlaves:
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+
 #   ┌─────────────────────┐
 #───┘ Redis configuration └─────────────────────────────────────
 
diff --git a/.config/example.yml b/.config/example.yml
index b61ed14809..57e2b56b78 100644
--- a/.config/example.yml
+++ b/.config/example.yml
@@ -51,6 +51,23 @@ db:
   #extra:
   #  ssl: true
 
+dbReplications: false
+
+# You can configure any number of replicas here
+#dbSlaves:
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+
 #   ┌─────────────────────┐
 #───┘ Redis configuration └─────────────────────────────────────
 
diff --git a/.devcontainer/devcontainer.yml b/.devcontainer/devcontainer.yml
index 1350e70157..2af306e3da 100644
--- a/.devcontainer/devcontainer.yml
+++ b/.devcontainer/devcontainer.yml
@@ -51,6 +51,23 @@ db:
   #extra:
   #  ssl: true
 
+dbReplications: false
+
+# You can configure any number of replicas here
+#dbSlaves:
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+
 #   ┌─────────────────────┐
 #───┘ Redis configuration └─────────────────────────────────────
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 615a3aad3c..2486a7e54f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -38,6 +38,8 @@
 - Add Minimizing ("folding") of windows
 
 ### Server
+- PostgreSQLのレプリケーション対応
+	- 設定ファイルの `dbReplications` および `dbSlaves` にて設定できます
 - イベント用Redisを別サーバーに分離できるように
 - ジョブキュー用Redisを別サーバーに分離できるように
 - サーバーの全体的なパフォーマンスを向上
diff --git a/chart/files/default.yml b/chart/files/default.yml
index 1d8e5b490a..1888669245 100644
--- a/chart/files/default.yml
+++ b/chart/files/default.yml
@@ -72,6 +72,23 @@ db:
   #extra:
   #  ssl: true
 
+dbReplications: false
+
+# You can configure any number of replicas here
+#dbSlaves:
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+#  -
+#    host: 
+#    port: 
+#    db: 
+#    user: 
+#    pass: 
+
 #   ┌─────────────────────┐
 #───┘ Redis configuration └─────────────────────────────────────
 
diff --git a/packages/backend/src/config.ts b/packages/backend/src/config.ts
index fd2b83cf2a..1443e63385 100644
--- a/packages/backend/src/config.ts
+++ b/packages/backend/src/config.ts
@@ -25,6 +25,16 @@ export type Source = {
 		disableCache?: boolean;
 		extra?: { [x: string]: string };
 	};
+	dbReplications?: boolean;
+	dbSlaves?: {
+		host: string;
+		port: number;
+		db: string;
+		user: string;
+		pass: string;
+		disableCache?: boolean;
+		extra?: { [x: string]: string };
+	}[];
 	redis: {
 		host: string;
 		port: number;
diff --git a/packages/backend/src/postgres.ts b/packages/backend/src/postgres.ts
index efeca46b49..bb21ed827e 100644
--- a/packages/backend/src/postgres.ts
+++ b/packages/backend/src/postgres.ts
@@ -200,6 +200,22 @@ export function createPostgresDataSource(config: Config) {
 			statement_timeout: 1000 * 10,
 			...config.db.extra,
 		},
+		replication: config.dbReplications ? {
+			master: {
+				host: config.db.host,
+				port: config.db.port,
+				username: config.db.user,
+				password: config.db.pass,
+				database: config.db.db,
+			},
+			slaves: config.dbSlaves!.map(rep => ({
+				host: rep.host,
+				port: rep.port,
+				username: rep.user,
+				password: rep.pass,
+				database: rep.db,
+			})),
+		} : undefined,
 		synchronize: process.env.NODE_ENV === 'test',
 		dropSchema: process.env.NODE_ENV === 'test',
 		cache: !config.db.disableCache && process.env.NODE_ENV !== 'test' ? { // dbをcloseしても何故かredisのコネクションが内部的に残り続けるようで、テストの際に支障が出るため無効にする(キャッシュも含めてテストしたいため本当は有効にしたいが...)