From 9cfb85e4dac9dd1d4d1a05dbb95a94deca014d27 Mon Sep 17 00:00:00 2001
From: Savas Vedova <savas@stormkit.io>
Date: Thu, 12 Oct 2023 14:38:52 +0200
Subject: [PATCH] chore: re-use invoke api logic

---
 src/middlewares/express.ts | 37 ++++++++++++------------------
 src/utils/callbacks.ts     | 47 ++++++++++++++++++++++++++------------
 2 files changed, 47 insertions(+), 37 deletions(-)

diff --git a/src/middlewares/express.ts b/src/middlewares/express.ts
index 171c713..600282a 100644
--- a/src/middlewares/express.ts
+++ b/src/middlewares/express.ts
@@ -1,6 +1,6 @@
-import type { Request, Response, Handler } from "express";
-import type { AlternativeSyntax } from "~/utils/callbacks";
+import type { Request, Response } from "express";
 import path from "node:path";
+import { invokeApiHandler } from "~/utils/callbacks";
 import { matchPath } from "~/router";
 
 interface Options {
@@ -34,29 +34,20 @@ export default (opts: Options) => async (req: Request, res: Response) => {
       `/${path.join(apiDir, route).replace(/^\/+/, "")}`
     );
 
-    Promise.resolve(handler.default(req, res, () => {})).then(
-      (r: AlternativeSyntax | void) => {
-        if (typeof r !== "undefined" && typeof r === "object") {
-          const isBodyAnObject = typeof r.body === "object";
-
-          if (isBodyAnObject) {
-            res.setHeader("Content-Type", "application/json");
-          }
-
-          Object.keys(r.headers || {}).forEach((key) => {
-            res.setHeader(key, r.headers![key]);
-          });
+    invokeApiHandler(handler, req, res).then((data) => {
+      if (!data) {
+        res.status(200);
+        res.end();
+        return;
+      }
 
-          res.status(r.status || r.statusCode || 200);
+      Object.keys(data.headers || {}).forEach((key) => {
+        res.setHeader(key, data.headers![key]);
+      });
 
-          if (isBodyAnObject) {
-            res.send(JSON.stringify(r.body));
-          } else {
-            res.send(r.body);
-          }
-        }
-      }
-    );
+      res.status(data.status || 200);
+      res.send(data.body);
+    });
 
     return;
   }
diff --git a/src/utils/callbacks.ts b/src/utils/callbacks.ts
index c86b928..258fdbe 100644
--- a/src/utils/callbacks.ts
+++ b/src/utils/callbacks.ts
@@ -34,11 +34,37 @@ let cachedFiles: WalkFile[];
 
 export interface AlternativeSyntax {
   body?: string;
-  headers?: Record<string, string>;
+  headers?: Record<string, string | string[]>;
   statusCode?: number;
   status?: number; // Alias for statusCode
 }
 
+export const invokeApiHandler = (
+  handler: any,
+  req: any,
+  res: any
+): Promise<ServerlessResponse | void> => {
+  const ret = handler?.default ? handler.default(req, res) : handler(req, res);
+
+  // Allow function to return a value instead of using `response.end`
+  return Promise.resolve(ret).then((r: AlternativeSyntax) => {
+    if (typeof r !== "undefined" && typeof r === "object") {
+      const isBodyAnObject = typeof r.body === "object";
+      const headers: Record<string, string | string[]> = {};
+
+      if (isBodyAnObject) {
+        headers["Content-Type"] = "application/json";
+      }
+
+      return {
+        body: typeof r.body === "string" ? r.body : JSON.stringify(r.body),
+        headers: { ...headers, ...r.headers },
+        status: r.statusCode || r.status,
+      };
+    }
+  });
+};
+
 export const handleApi = (
   event: RequestEvent,
   apiDir: string
@@ -47,7 +73,7 @@ export const handleApi = (
     cachedFiles = walkTree(apiDir);
   }
 
-  return new Promise((resolve) => {
+  return new Promise(async (resolve) => {
     const req = new Request(event);
     const res = new Response(req);
 
@@ -61,18 +87,11 @@ export const handleApi = (
     if (file) {
       try {
         const mod = require(path.join(file.path, file.name));
-        const ret = mod.default ? mod.default(req, res) : mod(req, res);
-
-        // Allow function to return a value instead of using `response.end`
-        Promise.resolve(ret).then((r: AlternativeSyntax) => {
-          if (typeof r !== "undefined" && typeof r === "object") {
-            resolve({
-              body: r.body,
-              headers: r.headers,
-              status: r.statusCode || r.status,
-            });
-          }
-        });
+        const ret = await invokeApiHandler(mod, req, res);
+
+        if (ret) {
+          resolve(ret);
+        }
 
         return;
       } catch (e) {