From 3a20e4726d9f8fe063129e00792d9f3dfe3a5649 Mon Sep 17 00:00:00 2001
From: Louis Lam <louislam@users.noreply.github.com>
Date: Mon, 28 Oct 2024 00:42:25 +0800
Subject: [PATCH] WIP

---
 server/database.js                            | 12 ++++++--
 .../utils/knex/lib/dialects/mysql2/index.js   | 20 +++++++++++++
 .../mysql2/schema/mysql2-columncompiler.js    | 30 +++++++++++++++++++
 3 files changed, 60 insertions(+), 2 deletions(-)
 create mode 100644 server/utils/knex/lib/dialects/mysql2/index.js
 create mode 100644 server/utils/knex/lib/dialects/mysql2/schema/mysql2-columncompiler.js

diff --git a/server/database.js b/server/database.js
index eb459435..4ba53bb8 100644
--- a/server/database.js
+++ b/server/database.js
@@ -190,6 +190,14 @@ class Database {
         fs.writeFileSync(path.join(Database.dataDir, "db-config.json"), JSON.stringify(dbConfig, null, 4));
     }
 
+    /**
+     * Get the MySQL2 Knex client
+     * @returns {KumaMySQL2} MySQL2 Knex client
+     */
+    static getMySQL2KnexClient() {
+        return require("./utils/knex/lib/dialects/mysql2/index");
+    }
+
     /**
      * Connect to the database
      * @param {boolean} testMode Should the connection be started in test mode?
@@ -261,7 +269,7 @@ class Database {
             connection.end();
 
             config = {
-                client: "mysql2",
+                client: Database.getMySQL2KnexClient(),
                 connection: {
                     host: dbConfig.hostname,
                     port: dbConfig.port,
@@ -284,7 +292,7 @@ class Database {
             await embeddedMariaDB.start();
             log.info("mariadb", "Embedded MariaDB started");
             config = {
-                client: "mysql2",
+                client: Database.getMySQL2KnexClient(),
                 connection: {
                     socketPath: embeddedMariaDB.socketPath,
                     user: "node",
diff --git a/server/utils/knex/lib/dialects/mysql2/index.js b/server/utils/knex/lib/dialects/mysql2/index.js
new file mode 100644
index 00000000..bfdc3f8b
--- /dev/null
+++ b/server/utils/knex/lib/dialects/mysql2/index.js
@@ -0,0 +1,20 @@
+const ClientMySQL2 = require("knex/lib/dialects/mysql2/index");
+const KumaColumnCompiler = require("./schema/mysql2-columncompiler");
+
+/**
+ * Fixed MySQL2 client class.
+ * - Fix: Default value for TEXT fields is not supported.
+ */
+class KumaMySQL2 extends ClientMySQL2 {
+
+    driverName = "mysql2";
+
+    /**
+     *
+     */
+    columnCompiler() {
+        return new KumaColumnCompiler(this, ...arguments);
+    }
+}
+
+module.exports = KumaMySQL2;
diff --git a/server/utils/knex/lib/dialects/mysql2/schema/mysql2-columncompiler.js b/server/utils/knex/lib/dialects/mysql2/schema/mysql2-columncompiler.js
new file mode 100644
index 00000000..b1cb2e1b
--- /dev/null
+++ b/server/utils/knex/lib/dialects/mysql2/schema/mysql2-columncompiler.js
@@ -0,0 +1,30 @@
+const ColumnCompilerMySQL = require("knex/lib/dialects/mysql/schema/mysql-columncompiler");
+const { isObject } = require("knex/lib/util/is");
+
+class KumaColumnCompiler extends ColumnCompilerMySQL {
+    /**
+     * Diff: Override defaultTo method to handle default value for TEXT fields
+     * @param {any} value Value
+     * @returns {string|void} Default value (Don't understand why it can return void or string, but it's the original code, lol)
+     */
+    defaultTo(value) {
+        // MySQL defaults to null by default, but breaks down if you pass it explicitly
+        // Note that in MySQL versions up to 5.7, logic related to updating
+        // timestamps when no explicit value is passed is quite insane - https://dev.mysql.com/doc/refman/5.7/en/server-system-variables.html#sysvar_explicit_defaults_for_timestamp
+        if (value === null || value === undefined) {
+            return;
+        }
+        if ((this.type === "json" || this.type === "jsonb") && isObject(value)) {
+            // Default value for json will work only it is an expression
+            return `default ('${JSON.stringify(value)}')`;
+        }
+        const defaultVal = super.defaultTo.apply(this, arguments);
+
+        // louislam deleted: (this.type !== "blob" && this.type.indexOf("text") === -1)
+        // Other code is the same as the original code
+        // See: https://github.com/louislam/uptime-kuma/pull/5048#discussion_r1818076626
+        return defaultVal;
+    }
+}
+
+module.exports = KumaColumnCompiler;