refactor: improve Vercel compatibility by handling SASL authentication and connection pooling in PostgreSQL configuration

Author: Marvin Zhang

.env.example

@@ -171,6 +171,7 @@ NODE_ENV="development"
 
 ## ======== VERCEL-SPECIFIC CONFIGURATION ========
 # Vercel Postgres (automatically provided by Vercel)
+# The system automatically prefers POSTGRES_URL_NON_POOLING over POSTGRES_URL to avoid SASL authentication issues
 # POSTGRES_URL="postgres://default:[email protected]:5432/verceldb"
 # POSTGRES_PRISMA_URL="postgres://default:[email protected]:5432/verceldb?pgbouncer=true&connect_timeout=15"
 # POSTGRES_URL_NON_POOLING="postgres://default:[email protected]:5432/verceldb"

docs/guides/VERCEL_DEPLOYMENT.md

@@ -100,6 +100,13 @@ If you encounter SSL certificate errors in Vercel deployment:
 - If needed, you can override by setting `POSTGRES_SSL="false"` in Vercel environment variables
 - For custom SSL configuration, set `POSTGRES_SSL='{"rejectUnauthorized":false,"ca":"..."}'`
 
+### SASL Authentication Errors (SCRAM-SERVER-FINAL-MESSAGE: server signature is missing)
+If you encounter SASL authentication errors:
+- This is automatically handled by using `POSTGRES_URL_NON_POOLING` when available
+- The system prefers direct connections over pooled connections to avoid authentication issues
+- Vercel automatically provides `POSTGRES_URL_NON_POOLING` which bypasses PgBouncer connection pooling
+- No manual configuration needed - the fix is automatic
+
 ### Auto-Detection Not Working
 - Check console logs for database detection messages
 - Ensure environment variable names match exactly: `POSTGRES_URL`, `MYSQL_URL`, `SQLITE_URL`

packages/core/src/utils/typeorm-config.ts

@@ -65,6 +65,21 @@ function parseSSLConfig(sslEnvVar?: string): boolean | object {
   }
 }
 
+/**
+ * Create additional PostgreSQL connection options for Vercel compatibility
+ */
+function getPostgresExtraOptions(): any {
+  return {
+    // Handle Vercel's connection pooling and authentication issues
+    connectionTimeoutMillis: 30000,
+    idleTimeoutMillis: 30000,
+    max: 1, // Limit connection pool size in serverless environment
+    // Additional options for SASL authentication stability
+    statement_timeout: 30000,
+    idle_in_transaction_session_timeout: 30000,
+  };
+}
+
 /**
  * Get or create the singleton DataSource instance
  * All services should use this to ensure they share the same database connection
@@ -145,6 +160,7 @@ export function createDataSource({
           type: 'postgres',
           url: options.url,
           ssl: options.ssl ?? false,
+          extra: getPostgresExtraOptions(),
         } as DataSourceOptions;
       } else {
         config = {
@@ -156,6 +172,7 @@ export function createDataSource({
           password: options.password,
           database: options.database,
           ssl: options.ssl ?? false,
+          extra: getPostgresExtraOptions(),
         } as DataSourceOptions;
       }
       break;
@@ -191,7 +208,9 @@ export function createDataSource({
  * Parse database configuration from environment variables
  */
 export function parseTypeORMConfig(): TypeORMStorageOptions {
-  const postgresUrl = process.env.POSTGRES_URL;
+  // For Vercel, prefer direct connection URLs that bypass connection pooling
+  // to avoid SASL authentication issues
+  const postgresUrl = process.env.POSTGRES_URL_NON_POOLING || process.env.POSTGRES_URL;
   const mysqlUrl = process.env.MYSQL_URL;
   const dbType = process.env.DEVLOG_STORAGE_TYPE?.toLowerCase();