feat(zod-openapi): support RPC-mode (#124)

* feat(zod-openapi): support RPC-mode

* changeset

* update readme

.changeset/big-students-yawn.md

@@ -0,0 +1,5 @@
+---
+'@hono/zod-openapi': minor
+---
+
+feat(zod-openapi): support RPC-mode

packages/zod-openapi/README.md

@@ -183,6 +183,24 @@ import { prettyJSON } from 'hono/pretty-json'
 app.use('/doc/*', prettyJSON())
 ```
 
+### RPC-mode
+
+Zod OpenAPI Hono supports Hono's RPC-mode. You can create the types for passing Hono Client:
+
+```ts
+import { hc } from 'hono/client'
+
+const appRoutes = app.openapi(route, (c) => {
+  const data = c.req.valid('json')
+  return c.jsonT({
+    id: data.id,
+    message: 'Success',
+  })
+})
+
+const client = hc<typeof appRoutes>('http://localhost:8787/')
+```
+
 ## References
 
 - [Hono](https://hono.dev/)

packages/zod-openapi/src/index.ts

@@ -11,7 +11,7 @@ import { extendZodWithOpenApi } from '@asteasolutions/zod-to-openapi'
 import type { OpenAPIObjectConfig } from '@asteasolutions/zod-to-openapi/dist/v3.0/openapi-generator'
 import { zValidator } from '@hono/zod-validator'
 import { Hono } from 'hono'
-import type { Context, Input, TypedResponse } from 'hono'
+import type { Context, Input, Schema, TypedResponse } from 'hono'
 import type { Env, Handler, MiddlewareHandler } from 'hono'
 import type { AnyZodObject, ZodSchema, ZodError } from 'zod'
 import { z, ZodType } from 'zod'
@@ -40,7 +40,7 @@ type IsForm<T> = T extends string
 
 type RequestPart<R extends RouteConfig, Part extends string> = Part extends keyof R['request']
   ? R['request'][Part]
-  : never
+  : {}
 
 type InputTypeBase<
   R extends RouteConfig,
@@ -49,6 +49,7 @@ type InputTypeBase<
 > = R['request'] extends RequestTypes
   ? RequestPart<R, Part> extends AnyZodObject
     ? {
+        in: { [K in Type]: z.input<RequestPart<R, Part>> }
         out: { [K in Type]: z.input<RequestPart<R, Part>> }
       }
     : {}
@@ -61,6 +62,11 @@ type InputTypeJson<R extends RouteConfig> = R['request'] extends RequestTypes
         ? {}
         : R['request']['body']['content'][keyof R['request']['body']['content']]['schema'] extends ZodSchema<any>
         ? {
+            in: {
+              json: z.input<
+                R['request']['body']['content'][keyof R['request']['body']['content']]['schema']
+              >
+            }
             out: {
               json: z.input<
                 R['request']['body']['content'][keyof R['request']['body']['content']]['schema']
@@ -79,6 +85,11 @@ type InputTypeForm<R extends RouteConfig> = R['request'] extends RequestTypes
         ? {}
         : R['request']['body']['content'][keyof R['request']['body']['content']]['schema'] extends ZodSchema<any>
         ? {
+            in: {
+              form: z.input<
+                R['request']['body']['content'][keyof R['request']['body']['content']]['schema']
+              >
+            }
             out: {
               form: z.input<
                 R['request']['body']['content'][keyof R['request']['body']['content']]['schema']
@@ -137,7 +148,7 @@ export class OpenAPIHono<E extends Env = Env, S = {}, BasePath extends string =
     route: R,
     handler: Handler<E, R['path'], I, OutputType<R>>,
     hook?: Hook<I, E, R['path'], OutputType<R>>
-  ) => {
+  ): Hono<E, Schema<R['method'], R['path'], I['in'], OutputType<R>>, BasePath> => {
     this.#registry.registerPath(route)
 
     const validators: MiddlewareHandler[] = []

packages/zod-openapi/test/index.test.ts

@@ -1,5 +1,9 @@
-// eslint-disable-next-line node/no-extraneous-import
-import { describe, it, expect } from 'vitest'
+/* eslint-disable node/no-extraneous-import */
+/* eslint-disable @typescript-eslint/no-explicit-any */
+import type { Env } from 'hono'
+import type { Hono } from 'hono'
+import { describe, it, expect, expectTypeOf } from 'vitest'
+import type { Schema } from 'zod'
 import { OpenAPIHono, createRoute, z } from '../src'
 
 describe('Basic - params', () => {
@@ -338,7 +342,7 @@ describe('Form', () => {
             schema: PostsSchema,
           },
         },
-        description: 'Get the posts',
+        description: 'Post the post',
       },
     },
   })
@@ -382,3 +386,75 @@ describe('Form', () => {
     expect(res.status).toBe(400)
   })
 })
+
+describe('Types', () => {
+  const RequestSchema = z.object({
+    id: z.number().openapi({}),
+    title: z.string().openapi({}),
+  })
+
+  const PostsSchema = z
+    .object({
+      id: z.number().openapi({}),
+      message: z.string().openapi({}),
+    })
+    .openapi('Post')
+
+  const route = createRoute({
+    method: 'post',
+    path: '/posts',
+    request: {
+      body: {
+        content: {
+          'application/json': {
+            schema: RequestSchema,
+          },
+        },
+      },
+    },
+    responses: {
+      200: {
+        content: {
+          'application/json': {
+            schema: PostsSchema,
+          },
+        },
+        description: 'Post the post',
+      },
+    },
+  })
+
+  const app = new OpenAPIHono()
+
+  const appRoutes = app.openapi(route, (c) => {
+    const data = c.req.valid('json')
+    return c.jsonT({
+      id: data.id,
+      message: 'Success',
+    })
+  })
+
+  it('Should return correct types', () => {
+    type H = Hono<
+      Env,
+      Schema<{
+        '/posts': {
+          $post: {
+            input: {
+              json: {
+                title: string
+                id: number
+              }
+            }
+            output: {
+              id: number
+              message: string
+            }
+          }
+        }
+      }>,
+      '/'
+    >
+    expectTypeOf(appRoutes).toMatchTypeOf<H>
+  })
+})