Lazily load hono

1 files changed, 18 insertions, 6 deletions

diff --git a/lib/server/hono/proxy.ts b/lib/server/hono/proxy.ts
index f729819..7f93804 100644
--- a/lib/server/hono/proxy.ts
+++ b/lib/server/hono/proxy.ts
@@ -10,21 +10,33 @@ import {
     TraceUtil,
 } from '@emprespresso/pengueno';
 
-import { serve, ServerType } from '@hono/node-server';
-import { Hono } from 'hono';
+import type { ServerType } from '@hono/node-server';
+import type { Hono } from 'hono';
 
 const AppLifetimeMetric = Metric.fromName('HonoAppLifetime').asResult();
 const AppRequestMetric = Metric.fromName('HonoAppRequest');
 
 export class HonoProxy {
-    private readonly app = LogMetricTraceable.of(new Hono())
-        .flatMap(TraceUtil.withTrace(`AppId = ${crypto.randomUUID()}`))
-        .flatMap(TraceUtil.withMetricTrace(AppLifetimeMetric));
+    private app?: LogMetricTraceable<Hono>;
 
     constructor(private readonly server: Server) {}
 
+    private async initializeApp() {
+        if (this.app) return this.app;
+
+        const { Hono } = await import('hono');
+        this.app = LogMetricTraceable.of(new Hono())
+            .flatMap(TraceUtil.withTrace(`AppId = ${crypto.randomUUID()}`))
+            .flatMap(TraceUtil.withMetricTrace(AppLifetimeMetric)) as LogMetricTraceable<Hono>;
+
+        return this.app;
+    }
+
     public async serve(port: number, hostname: string): Promise<IEither<Error, void>> {
-        return this.app
+        const { serve } = await import('@hono/node-server');
+
+        const app = await this.initializeApp();
+        return app
             .map((tApp) =>
                 Either.fromFailable<Error, ServerType>(() => {
                     const app = tApp.get();