Implement using pg_try_advisory_lock for db-migrations to be able to …

…run mulpile instances again

package.json

@@ -12,6 +12,8 @@
     "build": "tsc",
     "swagger": "tsoa spec-and-routes",
     "dev": "node --import tsx --watch src/index.ts",
+    "docker-compose-test:up": "docker compose -f compose.test.yml up -d",
+    "docker-compose-test:down": "docker compose -f compose.test.yml down",
     "backup": "docker exec -it badgehub-api-db-1 /usr/bin/pg_dump --username badgehub badgehub -f /var/backup/data-backup-`date +\"%Y-%m-%dT%H:%m\"`.sql",
     "overwrite-mockup-data": "docker exec -it badgehub-api-db-1 /usr/bin/pg_dump --username badgehub --schema badgehub badgehub > mockup-data.sql",
     "test": "vitest --coverage.enabled true",

process.json

@@ -4,7 +4,7 @@
   "interpreter_args": "--import tsx",
   "name": "badgehub",
   "exec_mode": "cluster",
-  "instances": 1,
+  "instances": 4,
   "error_file": "./logs/error.log",
   "out_file": "./logs/access.log",
   "combine_logs": true

src/db/connectionPool.ts

@@ -20,3 +20,13 @@ export const getPool = () => {
   }
   return pool;
 };
+
+export const getClient = () => {
+  return new pg.Client({
+    host: POSTGRES_HOST,
+    database: POSTGRES_DB,
+    user: POSTGRES_USER,
+    password: POSTGRES_PASSWORD,
+    port: POSTGRES_PORT,
+  });
+};

src/db/migrations.ts

@@ -1,19 +1,32 @@
 import { exec } from "node:child_process";
+import { getClient, getPool } from "@db/connectionPool";
+import sql from "sql-template-tag";
+
+const MIGRATION_LOCK_ID = 108;
 
 export async function runMigrations() {
   // This code runs the npm script 'db-migrate:up' to make sure all migrations are done
+  console.log(`Waiting for db-migrations lock ${MIGRATION_LOCK_ID}`);
+  const dbClient = getClient();
+  await dbClient.connect();
+  await dbClient.query(sql`SELECT pg_advisory_lock(${MIGRATION_LOCK_ID})`);
   console.log("Running migrations via child process");
-  return new Promise<void>((resolve, reject) => {
-    exec("npm run db-migrate:up", (error, stdout, stderr) => {
-      stdout && console.log(stdout);
-      stderr && console.error(stderr);
-      if (error) {
-        console.error(`Error running migrations: ${error}`);
-        reject(error);
-      } else {
-        resolve();
-      }
-      console.log("Migrations done");
+  try {
+    return await new Promise<void>((resolve, reject) => {
+      exec("npm run db-migrate:up", (error, stdout, stderr) => {
+        stdout && console.log(stdout);
+        stderr && console.error(stderr);
+        if (error) {
+          console.error(`Error running migrations: ${error}`);
+          reject(error);
+        } else {
+          resolve();
+        }
+        console.log("Migrations done");
+      });
     });
-  });
+  } finally {
+    await dbClient.end();
+    console.log("released db-migrations");
+  }
 }