fix: Remove charset parameter from MIME type of application/json

runtime-tests/lambda/index.test.ts

@@ -537,7 +537,7 @@ describe('AWS Lambda Adapter for Hono', () => {
         expect(albResponse.statusCode).toBe(200)
         expect(albResponse.headers).toEqual(
           expect.objectContaining({
-            'content-type': 'application/json; charset=UTF-8',
+            'content-type': 'application/json',
           })
         )
       })
@@ -598,7 +598,7 @@ describe('AWS Lambda Adapter for Hono', () => {
         expect(albResponse.multiValueHeaders).toBeDefined()
         expect(albResponse.multiValueHeaders).toEqual(
           expect.objectContaining({
-            'content-type': ['application/json; charset=UTF-8'],
+            'content-type': ['application/json'],
           })
         )
       })

src/adapter/aws-lambda/handler.test.ts

@@ -13,7 +13,7 @@ describe('isContentTypeBinary', () => {
     expect(isContentTypeBinary('text/javascript')).toBe(false)
     expect(isContentTypeBinary('application/json')).toBe(false)
     expect(isContentTypeBinary('application/ld+json')).toBe(false)
-    expect(isContentTypeBinary('application/json; charset=UTF-8')).toBe(false)
+    expect(isContentTypeBinary('application/json')).toBe(false)
   })
 })
 

src/adapter/lambda-edge/handler.test.ts

@@ -13,7 +13,7 @@ describe('isContentTypeBinary', () => {
     expect(isContentTypeBinary('text/javascript')).toBe(false)
     expect(isContentTypeBinary('application/json')).toBe(false)
     expect(isContentTypeBinary('application/ld+json')).toBe(false)
-    expect(isContentTypeBinary('application/json; charset=UTF-8')).toBe(false)
+    expect(isContentTypeBinary('application/json')).toBe(false)
   })
 })
 

src/context.test.ts

@@ -51,7 +51,7 @@ describe('Context', () => {
   it('c.json()', async () => {
     const res = c.json({ message: 'Hello' }, 201, { 'X-Custom': 'Message' })
     expect(res.status).toBe(201)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     const text = await res.text()
     expect(text).toBe('{"message":"Hello"}')
     expect(res.headers.get('X-Custom')).toBe('Message')
@@ -182,7 +182,7 @@ describe('Context', () => {
     c.status(404)
     const res = c.json({ hono: 'great app' })
     expect(res.status).toBe(404)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     const obj: { [key: string]: string } = await res.json()
     expect(obj['hono']).toBe('great app')
   })

src/context.ts

@@ -777,7 +777,7 @@ export class Context<
   ): JSONRespondReturn<T, U> => {
     const body = JSON.stringify(object)
     this.#preparedHeaders ??= {}
-    this.#preparedHeaders['content-type'] = 'application/json; charset=UTF-8'
+    this.#preparedHeaders['content-type'] = 'application/json'
     /* eslint-disable @typescript-eslint/no-explicit-any */
     return (
       typeof arg === 'number' ? this.#newResponse(body, arg, headers) : this.#newResponse(body, arg)

src/middleware/basic-auth/index.test.ts

@@ -295,7 +295,7 @@ describe('Basic Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(401)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe('{"message":"Custom unauthorized message as object"}')
   })
@@ -314,7 +314,7 @@ describe('Basic Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(401)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe('{"message":"Custom unauthorized message as function object"}')
   })

src/middleware/basic-auth/index.ts

@@ -120,7 +120,7 @@ export const basicAuth = (
             status,
             headers: {
               ...headers,
-              'content-type': 'application/json; charset=UTF-8',
+              'content-type': 'application/json',
             },
           })
     throw new HTTPException(status, { res })

src/middleware/bearer-auth/index.test.ts

@@ -400,7 +400,7 @@ describe('Bearer Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(401)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe('{"message":"Custom no authentication header message as object"}')
   })
@@ -423,7 +423,7 @@ describe('Bearer Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(401)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe(
       '{"message":"Custom no authentication header message as function object"}'
@@ -450,7 +450,7 @@ describe('Bearer Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(400)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe(
       '{"message":"Custom invalid authentication header message as object"}'
@@ -477,7 +477,7 @@ describe('Bearer Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(400)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe(
       '{"message":"Custom invalid authentication header message as function object"}'
@@ -500,7 +500,7 @@ describe('Bearer Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(401)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe('{"message":"Custom invalid token message as object"}')
   })
@@ -521,7 +521,7 @@ describe('Bearer Auth by Middleware', () => {
     const res = await app.request(req)
     expect(res).not.toBeNull()
     expect(res.status).toBe(401)
-    expect(res.headers.get('Content-Type')).toMatch('application/json; charset=UTF-8')
+    expect(res.headers.get('Content-Type')).toMatch('application/json')
     expect(handlerExecuted).toBeFalsy()
     expect(await res.text()).toBe('{"message":"Custom invalid token message as function object"}')
   })

src/middleware/bearer-auth/index.ts

@@ -103,7 +103,7 @@ export const bearerAuth = (options: BearerAuthOptions): MiddlewareHandler => {
             status,
             headers: {
               ...headers,
-              'content-type': 'application/json; charset=UTF-8',
+              'content-type': 'application/json',
             },
           })
     throw new HTTPException(status, { res })

src/utils/mime.test.ts

@@ -9,7 +9,7 @@ describe('mime', () => {
   it('getMimeType', () => {
     expect(getMimeType('hello.txt')).toBe('text/plain; charset=utf-8')
     expect(getMimeType('hello.html')).toBe('text/html; charset=utf-8')
-    expect(getMimeType('hello.json')).toBe('application/json; charset=utf-8')
+    expect(getMimeType('hello.json')).toBe('application/json')
     expect(getMimeType('favicon.ico')).toBe('image/x-icon')
     expect(getMimeType('good.morning.hello.gif')).toBe('image/gif')
     expect(getMimeType('goodmorninghellogif')).toBeUndefined()

src/utils/mime.ts

@@ -13,7 +13,7 @@ export const getMimeType = (
     return
   }
   let mimeType = mimes[match[1]]
-  if ((mimeType && mimeType.startsWith('text')) || mimeType === 'application/json') {
+  if (mimeType && mimeType.startsWith('text')) {
     mimeType += '; charset=utf-8'
   }
   return mimeType

src/validator/validator.test.ts

@@ -140,7 +140,7 @@ describe('JSON', () => {
     const res = await app.request('http://localhost/post', {
       method: 'POST',
       headers: {
-        'Content-Type': 'application/json; charset=utf8',
+        'Content-Type': 'application/json',
       },
       body: JSON.stringify({ foo: 'bar' }),
     })