add framework support for Hono (#539)

## Summary

Adds support for [Hono](https://hono.dev) framework.

Currently for `hono.test.ts`,
- 16/21 tests failing (76%)
- 3/21 tests passing (14%)

In comparison, other frameworks (e.g., Koa, Fastify) have:
- 6/21 tests failing (29%)
- 13/21 tests passing (62%)

## Checklist
<!-- Tick these items off as you progress. -->
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wrapping it in "~~"" and suffix it with "N/A My reason for skipping
this." -->
<!-- e.g. "- [ ] ~~Added tests~~ N/A Only touches docs" -->

- [ ] Added a [docs PR](https://github.com/inngest/website) that
references this PR
- [x] Added unit/integration tests
- [x] Added changesets if applicable

## Related
<!-- A space for any related links, issues, or PRs. -->
<!-- Linear issues are autolinked. -->
<!-- e.g. - INN-123 -->
<!-- GitHub issues/PRs can be linked using shorthand. -->
<!-- e.g. "- inngest/inngest#123" -->
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links.-->
- INN-

---------

Co-authored-by: Jack Williams <[email protected]>
Co-authored-by: Jack Williams <[email protected]>

.changeset/chatty-ducks-mate.md

@@ -0,0 +1,5 @@
+---
+"inngest": minor
+---
+
+Added framework support for Hono

examples/framework-hono/.gitignore

@@ -0,0 +1,10 @@
+node_modules
+dist
+.wrangler
+.dev.vars
+
+# Change them to your taste:
+package-lock.json
+yarn.lock
+pnpm-lock.yaml
+bun.lockb

examples/framework-hono/README.md

@@ -0,0 +1,36 @@
+# Inngest Hono Template
+
+This is a [Hono](https://hono.dev/) v4 project targetting Cloudflare Workers. It is a reference on how to send and receive events with Inngest and Hono.
+
+## Getting Started
+
+Use [`create-next-app`](https://www.npmjs.com/package/create-next-app) with [npm](https://docs.npmjs.com/cli/init), [Yarn](https://yarnpkg.com/lang/en/docs/cli/create/), or [pnpm](https://pnpm.io) to bootstrap the example:
+
+```bash
+npx create-next-app --example https://github.com/inngest/inngest-js/tree/main/examples/framework-hono inngest-hono
+```
+
+```bash
+yarn create next-app --example https://github.com/inngest/inngest-js/tree/main/examples/framework-hono inngest-hono
+```
+
+```bash
+pnpm create next-app --example https://github.com/inngest/inngest-js/tree/main/examples/framework-hono inngest-hono
+```
+
+### Run the app locally
+
+```sh
+npm install
+npm run dev
+```
+
+Open http://localhost:3000/api/inngest with your browser to see the result.
+
+- [Inngest functions](https://www.inngest.com/docs/functions) are available at `src/inngest/`.
+<!-- - The [Inngest handler](https://www.inngest.com/docs/sdk/serve#framework-hono) is available at `index.ts`. -->
+
+## Learn More
+
+- [Inngest Documentation](https://www.inngest.com/docs) - learn about the Inngest SDK, functions, and events
+- [Hono Documentation](https://hono.dev/top) - learn about Hono features and API

examples/framework-hono/package.json

@@ -0,0 +1,13 @@
+{
+  "scripts": {
+    "dev": "wrangler dev --port 3000 src/index.ts",
+    "deploy": "wrangler deploy --minify src/index.ts"
+  },
+  "dependencies": {
+    "hono": "^4.2.7"
+  },
+  "devDependencies": {
+    "@cloudflare/workers-types": "^4.20240403.0",
+    "wrangler": "^3.47.0"
+  }
+}

examples/framework-hono/src/index.ts

@@ -0,0 +1,16 @@
+import { Hono } from "hono";
+import { serve } from "inngest/hono";
+import { functions, inngest } from "./inngest";
+
+const app = new Hono();
+
+app.on(
+  ["GET", "PUT", "POST"],
+  "/api/inngest",
+  serve({
+    client: inngest,
+    functions,
+  })
+);
+
+export default app;

examples/framework-hono/src/inngest/client.ts

@@ -0,0 +1,4 @@
+import { Inngest } from "inngest";
+import { schemas } from "./types";
+
+export const inngest = new Inngest({ id: "my-bun-app", schemas });

examples/framework-hono/src/inngest/helloWorld.ts

@@ -0,0 +1,11 @@
+import { inngest } from "./client";
+
+export const helloWorld = inngest.createFunction(
+  { id: "hello-world" },
+  { event: "demo/event.sent" },
+  async ({ event, step }) => {
+    return {
+      message: `Hello ${event.name}!`,
+    };
+  }
+);

examples/framework-hono/src/inngest/index.ts

@@ -0,0 +1,5 @@
+import { helloWorld } from "./helloWorld";
+
+export const functions = [helloWorld];
+
+export { inngest } from "./client";

examples/framework-hono/src/inngest/types.ts

@@ -0,0 +1,10 @@
+import { EventSchemas } from "inngest";
+
+type DemoEventSent = {
+  name: "demo/event.sent";
+  data: {
+    message: string;
+  };
+};
+
+export const schemas = new EventSchemas().fromUnion<DemoEventSent>();

examples/framework-hono/tsconfig.json

@@ -0,0 +1,16 @@
+{
+  "compilerOptions": {
+    "target": "ESNext",
+    "module": "ESNext",
+    "moduleResolution": "Bundler",
+    "strict": true,
+    "lib": [
+      "ESNext"
+    ],
+    "types": [
+      "@cloudflare/workers-types"
+    ],
+    "jsx": "react-jsx",
+    "jsxImportSource": "hono/jsx"
+  },
+}

examples/framework-hono/wrangler.toml

@@ -0,0 +1,21 @@
+name = "framework-hono"
+compatibility_date = "2023-12-01"
+
+# [vars]
+# MY_VAR = "my-variable"
+
+# [[kv_namespaces]]
+# binding = "MY_KV_NAMESPACE"
+# id = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"
+
+# [[r2_buckets]]
+# binding = "MY_BUCKET"
+# bucket_name = "my-bucket"
+
+# [[d1_databases]]
+# binding = "DB"
+# database_name = "my-database"
+# database_id = ""
+
+# [ai]
+# binding = "AI"

packages/inngest/.eslintrc.js

@@ -42,6 +42,7 @@ module.exports = {
           "src/fastify.ts",
           "src/h3.ts",
           "src/koa.ts",
+          "src/hono.ts",
           "src/lambda.ts",
           "src/next.ts",
           "src/nuxt.ts",

packages/inngest/package.json

@@ -115,6 +115,11 @@
       "import": "./deno/fresh.js",
       "types": "./deno/fresh.d.ts"
     },
+    "./hono": {
+      "require": "./hono.js",
+      "import": "./hono.js",
+      "types": "./hono.d.ts"
+    },
     "./api/*": "./api/*.js",
     "./components/*": "./components/*.js",
     "./deno/*": "./deno/*.js",
@@ -210,6 +215,7 @@
     "fastify": "^4.21.0",
     "genversion": "^3.1.1",
     "glob": "^10.3.10",
+    "hono": "^4.2.3",
     "inquirer": "^9.2.10",
     "jest": "^29.3.1",
     "jest-fetch-mock": "^3.0.3",

packages/inngest/scripts/checkDependencies.ts

@@ -277,6 +277,7 @@ checkDependencies("tsconfig.build.json", [
   "src/fastify.ts",
   "src/h3.ts",
   "src/koa.ts",
+  "src/hono.ts",
   "src/lambda.ts",
   "src/next.ts",
   "src/nuxt.ts",

packages/inngest/src/hono.test.ts

@@ -0,0 +1,73 @@
+import * as HonoHandler from "@local/hono";
+import fetch, { Headers, Response } from "cross-fetch";
+import { testFramework } from "./test/helpers";
+
+const originalFetch = globalThis.fetch;
+const originalResponse = globalThis.Response;
+const originalHeaders = globalThis.Headers;
+
+testFramework("Hono", HonoHandler, {
+  /**
+   * Make sure this stuff is available for all polyfilled Node environments.
+   */
+  lifecycleChanges: () => {
+    beforeEach(() => {
+      jest.resetModules();
+      Object.defineProperties(globalThis, {
+        /**
+         * Fake a global `fetch` value, which is available as as a Web Standard
+         * API.
+         */
+        fetch: { value: fetch, configurable: true },
+        /**
+         * Fake a global `Response` class, which is used to create new responses
+         * for the handler.
+         */
+        Response: { value: Response, configurable: true },
+        /**
+         * Fake a global `Headers` class, which is used to create new Headers
+         * objects during response building.
+         */
+        Headers: { value: Headers, configurable: true },
+      });
+    });
+    afterEach(() => {
+      /**
+       * Reset all changes made to the global scope
+       */
+      Object.defineProperties(globalThis, {
+        fetch: { value: originalFetch, configurable: true },
+        Response: { value: originalResponse, configurable: true },
+        Headers: { value: originalHeaders, configurable: true },
+      });
+    });
+  },
+  transformReq: (req) => {
+    const c = {
+      req: {
+        // in practice, this is an absolute URL
+        url: new URL(`https://${req.headers["host"]}${req.url}`).href,
+        query: (key: string) =>
+          new URLSearchParams(req.url.split("?")[1] || "").get(key),
+        header: (key: string) => req.headers[key] as string,
+        method: req.method,
+        json: () => Promise.resolve(req.body),
+      },
+      body: (data: BodyInit, init: ResponseInit) => new Response(data, init),
+    };
+    return [c];
+  },
+  transformRes: async (_args, ret: Response) => {
+    const headers: Record<string, string> = {};
+
+    ret.headers.forEach((v, k) => {
+      headers[k] = v;
+    });
+
+    return {
+      status: ret.status,
+      body: await ret.text(),
+      headers,
+    };
+  },
+});

packages/inngest/src/hono.ts

@@ -0,0 +1,48 @@
+import { type Context } from "hono";
+import {
+  InngestCommHandler,
+  type ServeHandlerOptions,
+} from "./components/InngestCommHandler";
+import { type SupportedFrameworkName } from "./types";
+
+export const frameworkName: SupportedFrameworkName = "hono";
+
+/**
+ * Using Hono, serve and register any declared functions with Inngest,
+ * making them available to be triggered by events.
+ *
+ * @example
+ * ```ts
+ * const handler = serve({
+ *   client: inngest,
+ *   functions
+ * });
+ *
+ * app.use('/api/inngest',  async (c) => {
+ *   return handler(c);
+ * });
+ * ```
+ *
+ * @public
+ */
+export const serve = (options: ServeHandlerOptions) => {
+  const handler = new InngestCommHandler({
+    fetch: fetch.bind(globalThis),
+    frameworkName,
+    ...options,
+    handler: (c: Context) => {
+      return {
+        transformResponse: ({ headers, status, body }) => {
+          return c.body(body, { headers, status });
+        },
+        url: () => new URL(c.req.url, c.req.header("host")),
+        queryString: (key) => c.req.query(key),
+        headers: (key) => c.req.header(key),
+        method: () => c.req.method,
+        body: () => c.req.json(),
+      };
+    },
+  });
+
+  return handler.createHandler();
+};

packages/inngest/src/types.ts

@@ -1102,7 +1102,8 @@ export type SupportedFrameworkName =
   | "deno/fresh"
   | "sveltekit"
   | "fastify"
-  | "koa";
+  | "koa"
+  | "hono";
 
 /**
  * A set of options that can be passed to any step to configure it.