Add LiveQuery

src/LiveQuery/Subscription.js

@@ -0,0 +1,55 @@
+import {matchesQuery, queryHash} from './QueryTools';
+import PLog from './PLog';
+
+export type FlattenedObjectData = { [attr: string]: any };
+export type QueryData = { [attr: string]: any };
+
+class Subscription {
+  // It is query condition eg query.where
+  query: QueryData;
+  className: string;
+  hash: string;
+  clientRequestIds: Object;
+
+  constructor(className: string, query: QueryData, queryHash: string) {
+    this.className = className;
+    this.query = query;
+    this.hash = queryHash;
+    this.clientRequestIds = new Map();
+  }
+
+  addClientSubscription(clientId: number, requestId: number): void {
+    if (!this.clientRequestIds.has(clientId)) {
+      this.clientRequestIds.set(clientId, []);
+    }
+    let requestIds = this.clientRequestIds.get(clientId);
+    requestIds.push(requestId);
+  }
+
+  deleteClientSubscription(clientId: number, requestId: number): void {
+    let requestIds = this.clientRequestIds.get(clientId);
+    if (typeof requestIds === 'undefined') {
+      PLog.error('Can not find client %d to delete', clientId);
+      return;
+    }
+
+    let index = requestIds.indexOf(requestId);
+    if (index < 0) {
+      PLog.error('Can not find client %d subscription %d to delete', clientId, requestId);
+      return;
+    }
+    requestIds.splice(index, 1);
+    // Delete client reference if it has no subscription
+    if (requestIds.length == 0) {
+      this.clientRequestIds.delete(clientId);
+    }
+  }
+
+  hasSubscribingClient(): boolean {
+    return this.clientRequestIds.size > 0;
+  }
+}
+
+export {
+  Subscription
+}