Add redux actions/reducers for groups

ui/src/reducers/groupsReducer.ts

@@ -0,0 +1,45 @@
+import {
+  GroupsActionTypes,
+  LIST_GROUPS_BEGIN,
+  LIST_GROUPS_ERROR,
+  LIST_GROUPS_SUCCESS,
+} from "../actions/groupsActions";
+import { GroupInfo } from "../api";
+
+interface GroupsState {
+  loading: boolean;
+  data: GroupInfo[];
+  error: string;
+}
+
+const initialState: GroupsState = {
+  data: [],
+  loading: false,
+  error: "",
+};
+
+function groupsReducer(
+  state = initialState,
+  action: GroupsActionTypes
+): GroupsState {
+  switch (action.type) {
+    case LIST_GROUPS_BEGIN:
+      return { ...state, loading: true };
+
+    case LIST_GROUPS_ERROR:
+      return { ...state, loading: false, error: action.error };
+
+    case LIST_GROUPS_SUCCESS:
+      return {
+        ...state,
+        loading: false,
+        error: "",
+        data: action.payload.groups,
+      };
+
+    default:
+      return state;
+  }
+}
+
+export default groupsReducer;