Aggregation：查询汇总与稳定合并

顺序读取 App 数据，将重复项如何合并留在同一份配置中。

collect(inputs, context) 同步调用 execute，返回 {total,items}。未配置 key 时保留所有结果；配置 key 后按首次插入位置稳定合并，默认后项覆盖前项。merge(item,previous,input,context) 可决定保留哪个结果。execute、key、merge 必须同步。

mergeByKey 是独立的同类合并函数。它不查询数据库、不调用模型，不管理事务或权限；这些仍由真实读取端口负责。

由简到繁的同业务示例

顺序汇总两次读取

入门 · Node.js

TypeScript

import { Aggregation } from '@jangts/agent-core/kits/aggregation';
const pages = new Map([[1, [{ id: 'a', title: '第一页' }]], [2, [{ id: 'a', title: '重复项' }, { id: 'b', title: '第二页' }]]]);
const query = Aggregation.defineQueryAggregation({ execute: (page: number) => pages.get(page) ?? [] });
console.log(query.collect([1, 2], undefined));

JavaScript

import { Aggregation } from '@jangts/agent-core/kits/aggregation';
const pages = new Map([[1, [{ id: 'a', title: '第一页' }]], [2, [{ id: 'a', title: '重复项' }, { id: 'b', title: '第二页' }]]]);
const query = Aggregation.defineQueryAggregation({ execute: (page) => pages.get(page) ?? [] });
console.log(query.collect([1, 2], undefined));

同一 collect 增加主键与保留策略

配置 · Node.js

TypeScript

import { Aggregation } from '@jangts/agent-core/kits/aggregation';
type Row = { id: string; title: string };
const pages = new Map<number, Row[]>([[1, [{ id: 'a', title: '第一页' }]], [2, [{ id: 'a', title: '重复项' }, { id: 'b', title: '第二页' }]]]);
const query = Aggregation.defineQueryAggregation({
  execute: (page: number) => pages.get(page) ?? [],
  key: (row: Row) => row.id,
  merge: (row: Row, previous: Row | undefined) => previous ?? row,
});
console.log(query.collect([1, 2], undefined));
console.log(Aggregation.mergeByKey([...pages.values()].flat(), row => row.id, (row, previous) => previous ?? row));

JavaScript

import { Aggregation } from '@jangts/agent-core/kits/aggregation';
const pages = new Map([[1, [{ id: 'a', title: '第一页' }]], [2, [{ id: 'a', title: '重复项' }, { id: 'b', title: '第二页' }]]]);
const query = Aggregation.defineQueryAggregation({
    execute: (page) => pages.get(page) ?? [],
    key: (row) => row.id,
    merge: (row, previous) => previous ?? row,
});
console.log(query.collect([1, 2], undefined));
console.log(Aggregation.mergeByKey([...pages.values()].flat(), row => row.id, (row, previous) => previous ?? row));

策略与实现

• 稳定键合并与读取顺序