release: WRNexusJS 0.5.10

packages/db/src/client.ts

@@ -12,7 +12,9 @@
 import type { Db } from "./driver.ts";
 
 const DEFAULT = "default";
-const registry = new Map<string, Db>();
+type DbFactory = () => Db;
+type RegistryEntry = { db?: Db; factory?: DbFactory };
+const registry = new Map<string, RegistryEntry>();
 
 /** Set the default database (called by the runtime at startup). */
 export function setDb(db: Db): Db;
@@ -21,7 +23,7 @@ export function setDb(name: string, db: Db): Db;
 export function setDb(a: string | Db, b?: Db): Db {
   const name = typeof a === "string" ? a : DEFAULT;
   const db = typeof a === "string" ? b! : a;
-  registry.set(name, db);
+  registry.set(name, { db });
   return db;
 }
 
@@ -30,10 +32,18 @@ export function registerDb(name: string, db: Db): Db {
   return setDb(name, db);
 }
 
+/**
+ * Register a named database without opening its connection pool. The first
+ * `getDb(name)` call creates and caches the connection.
+ */
+export function registerLazyDb(name: string, factory: DbFactory): void {
+  registry.set(name, { factory });
+}
+
 /** The default database, or a named one. Throws if it isn't configured. */
 export function getDb(name = DEFAULT): Db {
-  const db = registry.get(name);
-  if (!db) {
+  const entry = registry.get(name);
+  if (!entry) {
     throw new Error(
       name === DEFAULT
         ? "No database configured. Add `db: { driver, url }` to wrnexus.config.ts."
@@ -41,7 +51,11 @@ export function getDb(name = DEFAULT): Db {
             `(e.g. databases: { ${name}: { driver, url } }).`,
     );
   }
-  return db;
+  if (!entry.db) {
+    if (!entry.factory) throw new Error(`Database '${name}' has no connection factory.`);
+    entry.db = entry.factory();
+  }
+  return entry.db;
 }
 
 /** Whether the default (or a named) database has been configured. */
@@ -56,6 +70,8 @@ export function databaseNames(): string[] {
 
 /** Close every configured database and clear the registry. */
 export async function closeDatabases(): Promise<void> {
-  for (const db of registry.values()) await db.close();
+  for (const entry of registry.values()) {
+    if (entry.db) await entry.db.close();
+  }
   registry.clear();
 }