implementation of server synchronization

src/app/core/cache/object-cache.reducer.ts

@@ -1,11 +1,15 @@
 import {
-  ObjectCacheAction, ObjectCacheActionTypes, AddToObjectCacheAction,
-  RemoveFromObjectCacheAction, ResetObjectCacheTimestampsAction, PatchObjectCacheAction
+  ObjectCacheAction,
+  ObjectCacheActionTypes,
+  AddToObjectCacheAction,
+  RemoveFromObjectCacheAction,
+  ResetObjectCacheTimestampsAction,
+  AddPatchObjectCacheAction, ApplyPatchObjectCacheAction
 } from './object-cache.actions';
 import { hasValue, isNotEmpty } from '../../shared/empty.util';
 import { CacheEntry } from './cache-entry';
 import { ResourceType } from '../shared/resource-type';
-import { Operation } from 'fast-json-patch';
+import { applyPatch, Operation } from 'fast-json-patch';
 
 export enum DirtyType {
   Created = 'Created',
@@ -13,7 +17,11 @@ export enum DirtyType {
   Deleted = 'Deleted'
 }
 
-/**
+export interface Patch {
+  uuid?: string;
+  operations: Operation[];
+}
+/**conca
  * An interface to represent objects that can be cached
  *
  * A cacheable object should have a self link
@@ -37,7 +45,8 @@ export class ObjectCacheEntry implements CacheEntry {
   timeAdded: number;
   msToLive: number;
   requestHref: string;
-  operations: Operation[];
+  patches: Patch[] = [];
+  isDirty: boolean;
 }
 
 /**
@@ -78,9 +87,14 @@ export function objectCacheReducer(state = initialState, action: ObjectCacheActi
       return resetObjectCacheTimestamps(state, action as ResetObjectCacheTimestampsAction)
     }
 
-    case ObjectCacheActionTypes.PATCH: {
-      return patchObjectCache(state, action as PatchObjectCacheAction);
+    case ObjectCacheActionTypes.ADD_PATCH: {
+      return addPatchObjectCache(state, action as AddPatchObjectCacheAction);
     }
+
+    case ObjectCacheActionTypes.APPLY_PATCH: {
+      return applyPatchObjectCache(state, action as ApplyPatchObjectCacheAction);
+    }
+
     default: {
       return state;
     }
@@ -104,7 +118,7 @@ function addToObjectCache(state: ObjectCacheState, action: AddToObjectCacheActio
       timeAdded: action.payload.timeAdded,
       msToLive: action.payload.msToLive,
       requestHref: action.payload.requestHref,
-      operations: []
+      isDirty: false
     }
   });
 }
@@ -156,16 +170,41 @@ function resetObjectCacheTimestamps(state: ObjectCacheState, action: ResetObject
  * @param state
  *    the current state
  * @param action
- *    a PatchObjectCacheAction
+ *    an AddPatchObjectCacheAction
  * @return ObjectCacheState
  *    the new state, with the new operations added to the state of the specified ObjectCacheEntry
  */
-function patchObjectCache(state: ObjectCacheState, action: PatchObjectCacheAction): ObjectCacheState {
-  const uuid = action.payload.uuid;
+function addPatchObjectCache(state: ObjectCacheState, action: AddPatchObjectCacheAction): ObjectCacheState {
+  const uuid = action.payload.href;
   const operations = action.payload.operations;
   const newState = Object.assign({}, state);
   if (hasValue(newState[uuid])) {
-    newState[uuid].operations = state[uuid].operations.concat(operations);
+    const patches = newState[uuid].patches;
+    newState[uuid].patches = [...patches, {operations} as Patch];
+    newState[uuid].isDirty = true;
+  }
+  return newState;
+}
+
+/**
+ * Apply the list of patch operations to a cached object
+ *
+ * @param state
+ *    the current state
+ * @param action
+ *    an ApplyPatchObjectCacheAction
+ * @return ObjectCacheState
+ *    the new state, with the new operations applied to the state of the specified ObjectCacheEntry
+ */
+function applyPatchObjectCache(state: ObjectCacheState, action: ApplyPatchObjectCacheAction): ObjectCacheState {
+  const uuid = action.payload;
+  const newState = Object.assign({}, state);
+  if (hasValue(newState[uuid])) {
+    // flatten two dimensional array
+    const flatPatch: Operation[] = [].concat(...newState[uuid].patches);
+    const newData = applyPatch( newState[uuid].data,  flatPatch);
+    newState[uuid].data =  newData.newDocument;
+    newState[uuid].patches = [];
   }
   return newState;
 }