Merge pull request #132 from DigiChanges/feat/NSE-135/MBL/mongoose-ag…

…gregate-paginator

feat/NSE-135/MBL/mongoose-aggregate-paginator

src/Shared/Infrastructure/Orm/MongooseAggregatePaginator.ts

@@ -0,0 +1,71 @@
+import { Aggregate } from 'mongoose';
+import IPaginator from './IPaginator';
+import IPaginatorConfig from './IPaginatorConfig';
+import ICriteria from '../../Presentation/Requests/ICriteria';
+import BasePaginator from './BasePaginator';
+
+class MongooseAggregatePaginator extends BasePaginator implements IPaginator
+{
+    private aggregate: Aggregate<any[]>;
+
+    constructor(aggregate: Aggregate<any[]>, criteria: ICriteria, config: IPaginatorConfig = { metadata: {}, helper: undefined })
+    {
+        super(criteria, config);
+        this.aggregate = aggregate;
+    }
+
+    public async paginate(): Promise<any>
+    {
+        this.addOrderBy();
+        this.addPagination();
+
+        this.setPerPage(this._perPage);
+        this.setCurrentPage();
+        this.setLasPage();
+        this.setFrom();
+        this.setTo();
+
+        let data = await this.aggregate.exec();
+        this.total = data.length;
+        this._perPage = data.length;
+
+        if (this.helper)
+        {
+            data = await this.helper(data);
+        }
+
+        return data;
+    }
+
+    // TODO: See when multiple sorts
+    private addOrderBy()
+    {
+        const sorts = this.sort.get();
+        const _objectSort = {};
+
+        sorts.forEach((value: string, key: string) =>
+        {
+            let order: any = value.toUpperCase();
+            order = (order === 'DESC') ? -1 : 1;
+
+            const obj = { [key]: order };
+            Object.assign(_objectSort, obj);
+        });
+
+        void this.aggregate.sort(_objectSort);
+    }
+
+    private addPagination()
+    {
+        const exist = this.pagination.getExist();
+
+        if (exist)
+        {
+            void this.aggregate
+                .skip(this.pagination.getOffset())
+                .limit(this.pagination.getLimit());
+        }
+    }
+}
+
+export default MongooseAggregatePaginator;