feat: warn when json validator does not find a content type in the request

src/validator/validator.test.ts

@@ -115,25 +115,25 @@ describe('JSON', () => {
     expect(data).toEqual({ foo: 'bar' })
   })
 
-  it('Should not validate if Content-Type is not set', async () => {
+  it('Should return 415 response if Content-Type is not set', async () => {
     const res = await app.request('http://localhost/post', {
       method: 'POST',
       body: JSON.stringify({ foo: 'bar' }),
     })
-    expect(res.status).toBe(200)
+    expect(res.status).toBe(415)
     const data = await res.json()
     expect(data.foo).toBeUndefined()
   })
 
-  it('Should not validate if Content-Type is wrong', async () => {
+  it('Should return 415 response if Content-Type is wrong', async () => {
     const res = await app.request('http://localhost/post', {
       method: 'POST',
       headers: {
         'Content-Type': 'text/plain;charset=utf-8',
       },
       body: JSON.stringify({ foo: 'bar' }),
     })
-    expect(res.status).toBe(200)
+    expect(res.status).toBe(415)
   })
 
   it('Should validate if Content-Type is a application/json with a charset', async () => {
@@ -231,6 +231,29 @@ describe('FormData', () => {
     expect(await res.json()).toEqual({ message: 'hi' })
   })
 
+  it('Should return 415 response if Content-Type is not set', async () => {
+    const formData = new FormData()
+    formData.append('message', 'hi')
+    const res = await app.request('http://localhost/post', {
+      method: 'POST',
+      body: formData,
+    })
+    expect(res.status).toBe(415)
+  })
+
+  it('Should return 415 response if Content-Type is wrong', async () => {
+    const formData = new FormData()
+    formData.append('message', 'hi')
+    const res = await app.request('http://localhost/post', {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'text/plain;charset=utf-8',
+      },
+      body: formData,
+    })
+    expect(res.status).toBe(415)
+  })
+
   it('Should validate a URL Encoded Data', async () => {
     const params = new URLSearchParams()
     params.append('foo', 'bar')

src/validator/validator.ts

@@ -27,6 +27,9 @@ const jsonRegex = /^application\/([a-z-\.]+\+)?json(;\s*[a-zA-Z0-9\-]+\=([^;]+))
 const multipartRegex = /^multipart\/form-data(;\s?boundary=[a-zA-Z0-9'"()+_,\-./:=?]+)?$/
 const urlencodedRegex = /^application\/x-www-form-urlencoded(;\s*[a-zA-Z0-9\-]+\=([^;]+))*$/
 
+const ERROR_MESSAGE_JSON = 'missing Content-Type header "application/json"'
+const ERROR_MESSAGE_FORM = 'missing Content-Type header "multipart/form-data" or "application/x-www-form-urlencoded"'
+
 export const validator = <
   InputType,
   P extends string,
@@ -72,6 +75,7 @@ export const validator = <
     switch (target) {
       case 'json':
         if (!contentType || !jsonRegex.test(contentType)) {
+          throw new HTTPException(415, { message: ERROR_MESSAGE_JSON })
           break
         }
         try {
@@ -86,6 +90,7 @@ export const validator = <
           !contentType ||
           !(multipartRegex.test(contentType) || urlencodedRegex.test(contentType))
         ) {
+          throw new HTTPException(415, { message: ERROR_MESSAGE_FORM })
           break
         }