Better handling of empty request bodies

httpbin/handlers_test.go

@@ -323,7 +323,18 @@ func TestHeaders(t *testing.T) {
 }
 
 func TestPost__EmptyBody(t *testing.T) {
+	var tests = []struct {
+		contentType string
+	}{
+		{""},
+		{"application/json; charset=utf-8"},
+		{"application/x-www-form-urlencoded"},
+		{"multipart/form-data; foo"},
+	}
+	for _, test := range tests {
+		t.Run("content type/"+test.contentType, func(t *testing.T) {
 			r, _ := http.NewRequest("POST", "/post", nil)
+			r.Header.Set("Content-Type", test.contentType)
 			w := httptest.NewRecorder()
 			handler.ServeHTTP(w, r)
 
@@ -336,12 +347,21 @@ func TestPost__EmptyBody(t *testing.T) {
 				t.Fatalf("failed to unmarshal body %s from JSON: %s", w.Body, err)
 			}
 
+			if resp.Data != "" {
+				t.Fatalf("expected empty response data, got %#v", resp.Data)
+			}
+			if resp.JSON != nil {
+				t.Fatalf("expected nil response json, got %#v", resp.JSON)
+			}
+
 			if len(resp.Args) > 0 {
 				t.Fatalf("expected no query params, got %#v", resp.Args)
 			}
 			if len(resp.Form) > 0 {
 				t.Fatalf("expected no form data, got %#v", resp.Form)
 			}
+		})
+	}
 }
 
 func TestPost__FormEncodedBody(t *testing.T) {

httpbin/helpers.go

@@ -121,7 +121,8 @@ func parseBody(w http.ResponseWriter, r *http.Request, resp *bodyResponse) error
 		}
 		resp.Form = r.PostForm
 	case strings.HasPrefix(ct, "application/json"):
-		if err := json.NewDecoder(r.Body).Decode(&resp.JSON); err != nil {
+		err := json.NewDecoder(r.Body).Decode(&resp.JSON)
+		if err != nil && err != io.EOF {
 			return err
 		}
 	}