Declare return types for API calls

Author: maprihoda

client/src/services/Api.js

@@ -22,15 +22,15 @@ class ApiService {
     this.client = client
   }
 
-  get(path: string): Promise<Array<Object>> {
+  get(path: string): Promise<Object> | Promise<Array<Object>> {
     return this.client.get(path).then(response => response.data)
   }
 
   post(path: string, payload: Object): Promise<Object> {
     return this.client.post(path, payload).then(response => response.data)
   }
 
-  patch(path: string, payload: Object) {
+  patch(path: string, payload: Object): Promise<Object> {
     return this.client.patch(path, payload).then(response => response.data)
   }
 

client/src/services/posts.js

@@ -1,10 +1,10 @@
 // @flow
 
-import type { Posts, Post } from '../types/posts'
+import type { Post, Posts } from '../types/posts'
 
 import service from './Api'
 
-export function fetchPostsFromApi(): Promise<Posts> {
+export function fetchPostsFromApi(): Promise<Post> | Promise<Posts> {
   return service.get('/posts')
 }