From d313d0093e97dea57879be9dfd43143275380010 Mon Sep 17 00:00:00 2001
From: Alex Yang <himself65@outlook.com>
Date: Mon, 4 Aug 2025 10:27:55 -0700
Subject: [PATCH] fix: await `ctx` in middleware (#3783)

* fix: await ctx in middleware

* fix: lint

* Create tidy-impalas-fail.md
---
 .changeset/tidy-impalas-fail.md            |  5 ++
 packages/better-auth/src/api/index.test.ts | 54 ++++++++++++++++++++++
 packages/better-auth/src/api/index.ts      |  3 +-
 3 files changed, 61 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/tidy-impalas-fail.md
 create mode 100644 packages/better-auth/src/api/index.test.ts

diff --git a/.changeset/tidy-impalas-fail.md b/.changeset/tidy-impalas-fail.md
new file mode 100644
index 0000000000..9ba9e12001
--- /dev/null
+++ b/.changeset/tidy-impalas-fail.md
@@ -0,0 +1,5 @@
+---
+"better-auth": patch
+---
+
+fix: await `ctx` in middleware
diff --git a/packages/better-auth/src/api/index.test.ts b/packages/better-auth/src/api/index.test.ts
new file mode 100644
index 0000000000..5391c1ae0c
--- /dev/null
+++ b/packages/better-auth/src/api/index.test.ts
@@ -0,0 +1,54 @@
+import { describe, expect, it, vi } from "vitest";
+import { getEndpoints } from "./index";
+import type { AuthContext } from "../init";
+import type { BetterAuthOptions, BetterAuthPlugin } from "../types";
+import { createAuthMiddleware } from "./call";
+
+describe("getEndpoints", () => {
+	it("should await promise-based context before passing to middleware", async () => {
+		const mockContext: AuthContext = {
+			baseURL: "http://localhost:3000",
+			options: {},
+		} as any;
+
+		const middlewareFn = vi.fn().mockResolvedValue({});
+
+		const testPlugin: BetterAuthPlugin = {
+			id: "test-plugin",
+			middlewares: [
+				{
+					path: "/test",
+					middleware: createAuthMiddleware(async (ctx) => {
+						middlewareFn(ctx);
+						return {};
+					}),
+				},
+			],
+		};
+
+		const options: BetterAuthOptions = {
+			plugins: [testPlugin],
+		};
+
+		const promiseContext = new Promise<AuthContext>((resolve) => {
+			setTimeout(() => resolve(mockContext), 10);
+		});
+
+		const { middlewares } = getEndpoints(promiseContext, options);
+
+		const testCtx = {
+			request: new Request("http://localhost:3000/test"),
+			context: { customProp: "value" },
+		};
+
+		await middlewares[0].middleware(testCtx);
+
+		expect(middlewareFn).toHaveBeenCalled();
+		const call = middlewareFn.mock.calls[0][0];
+		expect(call.context).toMatchObject({
+			baseURL: "http://localhost:3000",
+			options: {},
+			customProp: "value",
+		});
+	});
+});
diff --git a/packages/better-auth/src/api/index.ts b/packages/better-auth/src/api/index.ts
index 075b518ee0..7da3884165 100644
--- a/packages/better-auth/src/api/index.ts
+++ b/packages/better-auth/src/api/index.ts
@@ -72,10 +72,11 @@ export function getEndpoints<
 			?.map((plugin) =>
 				plugin.middlewares?.map((m) => {
 					const middleware = (async (context: any) => {
+						const authContext = await ctx;
 						return m.middleware({
 							...context,
 							context: {
-								...ctx,
+								...authContext,
 								...context.context,
 							},
 						});