feat: Abstract transport layer and allow passing custom options

aklinker1 · aklinker1 · commit 52c01ece3297 · 2025-11-25T14:46:38.000-06:00
diff --git a/src/app.ts b/src/app.ts
@@ -13,9 +13,14 @@ import type {
   DefaultAppData,
   BasePrefix,
   SchemaAdapter,
+  Transport,
 } from "./types";
 import { addRoute, createRouter, findRoute } from "rou3";
-import { callCtxModifierHooks, serializeErrorResponse } from "./internal/utils";
+import {
+  callCtxModifierHooks,
+  detectTransport,
+  serializeErrorResponse,
+} from "./internal/utils";
 import type { OpenAPIV3_1 } from "openapi-types";
 import { buildOpenApiDocs, buildScalarHtml } from "./open-api";
 
@@ -227,17 +232,8 @@ export function createApp<TPrefix extends BasePrefix = "">(
     },
 
     listen: (port, cb) => {
-      if (typeof Bun !== "undefined") {
-        Bun.serve({ port, fetch: app.build() });
-        if (cb) setTimeout(cb, 0);
-      } else if (
-        // @ts-expect-error: Deno types not installed.
-        typeof Deno !== "undefined"
-      ) {
-        // @ts-expect-error: Deno types not installed.
-        Deno.serve({ port, fetch: app.build() });
-        if (cb) setTimeout(cb, 0);
-      }
+      const transport = options?.transport ?? detectTransport();
+      transport.listen(port, app.build(), cb);
       return app;
     },
 
@@ -428,6 +424,24 @@ export type CreateAppOptions<TPrefix extends BasePrefix = ""> = {
    */
   schemaAdapter?: SchemaAdapter;
 
+  /**
+   * Tell Zeta how to serve your app over a port. By default, Zeta will detect
+   * if you're runtime is Bun or Deno, and use the appropriate transport.
+   *
+   * If you need to customize the transport, like adding an `idleTimeout` to
+   * bun, you can do so by passing options into the transport's factory function.
+   *
+   * @example
+   * ```ts
+   * import { createBunTransport } from "@aklinker1/zeta/transports/bun-transport"
+   *
+   * const app = createApp({
+   *   transport: createBunTransport(),
+   * });
+   * ```
+   */
+  transport?: Transport;
+
   /**
    * Where the OpenAPI JSON docs is hosted.
    * @default "/openapi.json"
diff --git a/src/internal/utils.ts b/src/internal/utils.ts
@@ -7,9 +7,12 @@ import type {
   MaybePromise,
   RouterData,
   StatusResult,
+  Transport,
 } from "../types";
 import type { MatchedRoute } from "rou3";
 import type { ErrorResponse } from "../custom-responses";
+import { createBunTransport } from "../transports/bun-transport";
+import { createDenoTransport } from "../transports/deno-transport";
 
 export function validateSchema<T>(
   schema: StandardSchemaV1<T, T>,
@@ -136,3 +139,22 @@ export const IsStatusResult = Symbol("IsStatusResult");
 export function isStatusResult(result: any): result is StatusResult {
   return IsStatusResult in result;
 }
+
+export function detectTransport(): Transport {
+  // @ts-ignore: Bun types may not be available
+  if (typeof Bun !== "undefined") return createBunTransport();
+  // @ts-ignore: Deno types may not be available
+  if (typeof Deno !== "undefined") return createDenoTransport();
+
+  throw Error(`Cannot automatically detect which transport to use. You must specify a transport in your top-level app:
+
+    ---
+    import { createBunTransport } from '@aklinker1/zeta/transports/bun-transport';
+
+    const app = createApp({
+      transport: createBunTransport(),
+    })
+
+    app.listen();
+    ---`);
+}
diff --git a/src/transports/bun-transport.ts b/src/transports/bun-transport.ts
@@ -0,0 +1,17 @@
+import type { Transport } from "../types";
+// @ts-ignore: Bun types may not be available
+import type { ServeFunctionOptions } from "bun";
+
+export function createBunTransport(
+  options: Omit<ServeFunctionOptions<any, any>, "fetch" | "port">,
+): Transport {
+  const listen: Transport["listen"] = (port, fetch, cb) => {
+    // @ts-ignore: Bun types may not be available
+    Bun.serve({ ...options, port, fetch });
+    if (cb) setTimeout(cb, 0);
+  };
+
+  return {
+    listen,
+  };
+}
diff --git a/src/transports/deno-transport.ts b/src/transports/deno-transport.ts
@@ -0,0 +1,13 @@
+import type { Transport } from "../types";
+
+export function createDenoTransport(): Transport {
+  const listen: Transport["listen"] = (port, fetch, cb) => {
+    // @ts-ignore: Deno types may not be available
+    Deno.serve({ port, fetch });
+    if (cb) setTimeout(cb, 0);
+  };
+
+  return {
+    listen,
+  };
+}
diff --git a/src/types.ts b/src/types.ts
@@ -1042,6 +1042,14 @@ export interface SchemaAdapter {
   getMeta: (schema: StandardSchemaV1) => Record<string, any> | undefined;
 }
 
+//
+// TRANSPORTS
+//
+
+export interface Transport {
+  listen: (port: number, fetch: ServerSideFetch, cb?: () => void) => void;
+}
+
 //
 // SETTER
 //
