fix(zod-openapi): don't validate the body if content-type is mismatched (#686)

* fix(zod-openapi): don't validate the body if content-type is mismatched

* changeset

.changeset/orange-ducks-itch.md

@@ -0,0 +1,5 @@
+---
+'@hono/zod-openapi': patch
+---
+
+fix: don't validate the body if content-type is mismatched

packages/zod-openapi/package.json

@@ -42,7 +42,7 @@
   },
   "devDependencies": {
     "@cloudflare/workers-types": "^4.20240117.0",
-    "hono": "^4.3.6",
+    "hono": "^4.5.4",
     "jest": "^29.7.0",
     "tsup": "^8.0.1",
     "typescript": "^5.4.4",

packages/zod-openapi/src/index.ts

@@ -54,12 +54,12 @@ type RequestTypes = {
 }
 
 type IsJson<T> = T extends string
-    ? T extends `application/${infer Start}json${infer _End}`
-        ? Start extends '' | `${string}+` | `vnd.${string}+`
-            ? 'json'
-            : never
-        : never
+  ? T extends `application/${infer Start}json${infer _End}`
+    ? Start extends '' | `${string}+` | `vnd.${string}+`
+      ? 'json'
+      : never
     : never
+  : never
 
 type IsForm<T> = T extends string
   ? T extends
@@ -259,6 +259,17 @@ export type OpenAPIObjectConfigure<E extends Env, P extends string> =
   | OpenAPIObjectConfig
   | ((context: Context<E, P>) => OpenAPIObjectConfig)
 
+const isJSONContentType = (contentType: string) => {
+  return /^application\/([a-z-\.]+\+)?json/.test(contentType)
+}
+
+const isFormContentType = (contentType: string) => {
+  return (
+    contentType.startsWith('multipart/form-data') ||
+    contentType.startsWith('application/x-www-form-urlencoded')
+  )
+}
+
 export class OpenAPIHono<
   E extends Env = Env,
   S extends Schema = {},
@@ -390,16 +401,31 @@ export class OpenAPIHono<
         if (!(schema instanceof ZodType)) {
           continue
         }
-        if (/^application\/([a-z-\.]+\+)?json/.test(mediaType)) {
+        if (isJSONContentType(mediaType)) {
           const validator = zValidator('json', schema, hook as any)
-          validators.push(validator as any)
+          const mw: MiddlewareHandler = async (c, next) => {
+            if (c.req.header('content-type')) {
+              if (isJSONContentType(c.req.header('content-type')!)) {
+                return await validator(c, next)
+              }
+            }
+            c.req.addValidatedData('json', {})
+            await next()
+          }
+          validators.push(mw)
         }
-        if (
-          mediaType.startsWith('multipart/form-data') ||
-          mediaType.startsWith('application/x-www-form-urlencoded')
-        ) {
+        if (isFormContentType(mediaType)) {
           const validator = zValidator('form', schema, hook as any)
-          validators.push(validator as any)
+          const mw: MiddlewareHandler = async (c, next) => {
+            if (c.req.header('content-type')) {
+              if (isFormContentType(c.req.header('content-type')!)) {
+                return await validator(c, next)
+              }
+            }
+            c.req.addValidatedData('form', {})
+            await next()
+          }
+          validators.push(mw)
         }
       }
     }

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

@@ -228,7 +228,7 @@ describe('coerce', () => {
     type Actual = ExtractSchema<typeof routes>['/api/users/:id']['$get']['input']
     type Expected = {
       param: {
-        id: string | undefined
+        id: string
       }
     }
     type verify = Expect<Equal<Expected, Actual>>

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

@@ -2,7 +2,7 @@ import type { RouteConfig } from '@asteasolutions/zod-to-openapi'
 import type { Context, TypedResponse } from 'hono'
 import { bearerAuth } from 'hono/bearer-auth'
 import { hc } from 'hono/client'
-import { describe, expect, expectTypeOf, it } from 'vitest'
+import { describe, expect, expectTypeOf, it, vi } from 'vitest'
 import type { RouteConfigToTypedResponse } from '../src/index'
 import { OpenAPIHono, createRoute, z } from '../src/index'
 import type { Equal, Expect } from 'hono/utils/types'
@@ -450,7 +450,7 @@ describe('JSON', () => {
     const app = new OpenAPIHono()
 
     app.openapi(route, (c) => {
-      const {id, title} = c.req.valid('json')
+      const { id, title } = c.req.valid('json')
       return c.json({
         id,
         title,
@@ -489,6 +489,14 @@ describe('JSON', () => {
       const res = await app.request(req)
       expect(res.status).toBe(400)
     })
+
+    it('Should return 200 response without a content-type', async () => {
+      const req = new Request('http://localhost/posts', {
+        method: 'POST',
+      })
+      const res = await app.request(req)
+      expect(res.status).toBe(200)
+    })
   })
 
   describe('Content-Type application/vnd.api+json', () => {
@@ -519,7 +527,7 @@ describe('JSON', () => {
     const app = new OpenAPIHono()
 
     app.openapi(route, (c) => {
-      const {id, title} = c.req.valid('json')
+      const { id, title } = c.req.valid('json')
       return c.json({
         id,
         title,
@@ -641,12 +649,76 @@ describe('Form', () => {
     })
   })
 
-  it('Should return 400 response with correct contents', async () => {
+  it('Should return 200 response without a content-type', async () => {
     const req = new Request('http://localhost/posts', {
       method: 'POST',
     })
     const res = await app.request(req)
-    expect(res.status).toBe(400)
+    expect(res.status).toBe(200)
+  })
+})
+
+describe('JSON and Form', () => {
+  const functionInForm = vi.fn()
+  const functionInJSON = vi.fn()
+  const route = createRoute({
+    method: 'post',
+    path: '/hello',
+    request: {
+      body: {
+        content: {
+          'application/x-www-form-urlencoded': {
+            schema: z.custom(() => {
+              functionInForm()
+              return true
+            }),
+          },
+          'application/json': {
+            schema: z.custom(() => {
+              functionInJSON()
+              return true
+            }),
+          },
+        },
+      },
+    },
+    responses: {
+      200: {
+        description: 'response',
+      },
+    },
+  })
+
+  const app = new OpenAPIHono()
+
+  app.openapi(route, (c) => {
+    return c.json(0)
+  })
+
+  test('functionInJSON should not be called when the body is Form', async () => {
+    const form = new FormData()
+    form.append('foo', 'foo')
+    await app.request('/hello', {
+      method: 'POST',
+      body: form,
+    })
+    expect(functionInForm).toHaveBeenCalled()
+    expect(functionInJSON).not.toHaveBeenCalled()
+    functionInForm.mockReset()
+    functionInJSON.mockReset()
+  })
+  test('functionInForm should not be called when the body is JSON', async () => {
+    await app.request('/hello', {
+      method: 'POST',
+      body: JSON.stringify({ foo: 'foo' }),
+      headers: {
+        'content-type': 'application/json',
+      },
+    })
+    expect(functionInForm).not.toHaveBeenCalled()
+    expect(functionInJSON).toHaveBeenCalled()
+    functionInForm.mockReset()
+    functionInJSON.mockReset()
   })
 })
 

packages/zod-openapi/yarn.lock

@@ -594,7 +594,7 @@ __metadata:
     "@asteasolutions/zod-to-openapi": "npm:^7.1.0"
     "@cloudflare/workers-types": "npm:^4.20240117.0"
     "@hono/zod-validator": "npm:0.2.2"
-    hono: "npm:^4.3.6"
+    hono: "npm:^4.5.4"
     jest: "npm:^29.7.0"
     tsup: "npm:^8.0.1"
     typescript: "npm:^5.4.4"
@@ -2379,10 +2379,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"hono@npm:^4.3.6":
-  version: 4.4.6
-  resolution: "hono@npm:4.4.6"
-  checksum: 065318f3fe021320b59f3daddacf7d74bfc3303de55f415a999b6967a9f09714e136528bc86cc880a45633cd85dec5428e41e902b5e3a3809f3cd17204302668
+"hono@npm:^4.5.4":
+  version: 4.5.4
+  resolution: "hono@npm:4.5.4"
+  checksum: 980accb9567fe5ba4533c1378d175a95a0eef0a1fa8a03ceb1f9296d88d4ee8ff0e1447f5e69eb56150a8b6cc66f4a663ec9d1c1135f005f44f61353b58e276f
   languageName: node
   linkType: hard