refactored requestCacheReducer

src/app/core/index/href-index.reducer.ts

@@ -0,0 +1,43 @@
+import {
+  HrefIndexAction, HrefIndexActionTypes, AddToHrefIndexAction,
+  RemoveUUIDFromHrefIndexAction
+} from "./href-index.actions";
+export interface HrefIndexState {
+  [href: string]: string
+}
+
+// Object.create(null) ensures the object has no default js properties (e.g. `__proto__`)
+const initialState: HrefIndexState = Object.create(null);
+
+export const hrefIndexReducer = (state = initialState, action: HrefIndexAction): HrefIndexState => {
+  switch (action.type) {
+
+    case HrefIndexActionTypes.ADD: {
+      return addToHrefIndex(state, <AddToHrefIndexAction>action);
+    }
+
+    case HrefIndexActionTypes.REMOVE_UUID: {
+      return removeUUIDFromHrefIndex(state, <RemoveUUIDFromHrefIndexAction>action)
+    }
+
+    default: {
+      return state;
+    }
+  }
+};
+
+function addToHrefIndex(state: HrefIndexState, action: AddToHrefIndexAction): HrefIndexState {
+  return Object.assign({}, state, {
+    [action.payload.href]: action.payload.uuid
+  });
+}
+
+function removeUUIDFromHrefIndex(state: HrefIndexState, action: RemoveUUIDFromHrefIndexAction): HrefIndexState {
+  let newState = Object.create(null);
+  for (let href in state) {
+    if (state[href] !== action.payload) {
+      newState[href] = state[href];
+    }
+  }
+  return newState;
+}