fix(fetcher): do not send json content type with empty body

Author: CalebM1987

src/fetcher.ts

@@ -131,7 +131,9 @@ function getFetchParams(request: Request): {
   const path = getPath(request.path, payload)
   const query = getQuery(request.method, payload, request.queryParams)
   const body = getBody(request.method, payload)
-  const headers = getHeaders(body, request.init?.headers)
+  const headers = sendBody(request.method)
+    ? getHeaders(body, request.init?.headers)
+    : new Headers(request.init?.headers)
   const url = request.baseUrl + path + query
 
   const init = {

test/fetch.test.ts

@@ -24,12 +24,12 @@ describe('fetch', () => {
 
   const expectedHeaders = {
     authorization: 'Bearer token',
-    accept: 'application/json',
   }
 
-  const headersWithContentType = {
+  const expectedHeadersWithBody = {
     ...expectedHeaders,
     'content-type': 'application/json',
+    accept: 'application/json',
   }
 
   it('GET /query/{a}/{b}', async () => {
@@ -64,7 +64,7 @@ describe('fetch', () => {
       expect(data.params).toEqual({ id: '1' })
       expect(data.body).toEqual({ list: ['b', 'c'] })
       expect(data.query).toEqual({})
-      expect(data.headers).toEqual(headersWithContentType)
+      expect(data.headers).toEqual(expectedHeadersWithBody)
     })
   })
 
@@ -77,7 +77,7 @@ describe('fetch', () => {
       expect(data.params).toEqual({ id: '1' })
       expect(data.body).toEqual(['b', 'c'])
       expect(data.query).toEqual({})
-      expect(data.headers).toEqual(headersWithContentType)
+      expect(data.headers).toEqual(expectedHeadersWithBody)
     })
   })
 
@@ -97,7 +97,7 @@ describe('fetch', () => {
       expect(data.params).toEqual({ id: '1' })
       expect(data.body).toEqual({ list: ['b', 'c'] })
       expect(data.query).toEqual({ scalar: 'a' })
-      expect(data.headers).toEqual(headersWithContentType)
+      expect(data.headers).toEqual(expectedHeadersWithBody)
     })
   })