Added group_categories model file, redux

• Added:
- group_categories model file, redux

app/javascript/gabsocial/actions/group_categories.js

@@ -0,0 +1,27 @@
+import api from '../api'
+
+export const GROUP_CATEGORIES_FETCH_REQUEST = 'GROUP_CATEGORIES_FETCH_REQUEST'
+export const GROUP_CATEGORIES_FETCH_SUCCESS = 'GROUP_CATEGORIES_FETCH_SUCCESS'
+export const GROUP_CATEGORIES_FETCH_FAIL = 'GROUP_CATEGORIES_FETCH_FAIL'
+
+export const fetchGroupCategories = () => (dispatch, getState) => {
+  dispatch(fetchGroupCategoriesRequest())
+
+  api(getState).get('/api/v1/group_categories')
+    .then(({ data }) => dispatch(fetchGroupCategoriesSuccess(data)))
+    .catch(err => dispatch(fetchGroupCategoriesFail(err)))
+}
+
+export const fetchGroupCategoriesRequest = () => ({
+  type: GROUP_CATEGORIES_FETCH_REQUEST,
+})
+
+export const fetchGroupCategoriesSuccess = (categories) => ({
+  type: GROUP_CATEGORIES_FETCH_SUCCESS,
+  categories,
+})
+
+export const fetchGroupCategoriesFail = (error) => ({
+  type: GROUP_CATEGORIES_FETCH_FAIL,
+  error,
+})