使用数组来链式记录账户的余额

account.chain.ts

import { MongoClient } from 'mongodb';
const url = 'mongodb://localhost:27017';
const dbName = 'test-set';
import { ConsolePro } from "console-pro";
const console = new ConsolePro();

/**等待n毫秒 */
function sleep(ms: number) {
    return new Promise(cb => setTimeout(cb, ms));
}
/**模拟链的高度 */
function getHeight() {
    return Math.floor((Date.now() - 1526614267805) / 3e3/* 3s一个高度 */);
}
/**这一轮开始操作的height，小于这个height意味着上一轮 */
const current_round_start_height = getHeight();

console.log("START")
MongoClient.connect(url, async function (err, client) {
    try {

        console.log("CONNECTED")
        const db = client.db(dbName);
        const collection = db.collection("t1");
        /* 1. 配置索引 */
        collection.createIndex({ name: 1 }, {
            unique: true
        });
        collection.createIndex({ "chain.height": -1 }, {
            // unique: true
        });
        /* 2. 生成账户并插入（这里方便测试，只搞两个账户） */
        const accounts = Array.from({ length: 2 }, (_, i) => {
            return {
                name: "test" + i,
                chain: [{ balance: 0, height: 0 }] as any[]// 每一次更新都是新增一条记录
            }
        });
        {
            const num = await collection.count({});
            if (accounts.length > num) {
                await collection.insertMany(accounts.slice(num));// 插入账户数据，只插入不存在的
            }
        }

        /* 3. 每个账户随机更新账户 */
        const records_list = await Promise.all(accounts.map(async (account) => {
            let update_counts = 5;// 更新次数// 随机的更新次数
            const records = [] as any[]
            for (let i = 0; i < update_counts; i += 1) {
                const current_height = getHeight();
                const new_balance = (Math.random() * 1000) | 0;
                const record = [current_height, new_balance];

                const g = console.group(console.flagHead(account.name, false), record);

                records.push(record);
                const updateRes = await collection.updateOne(
                    { name: account.name, "chain.height": current_height },
                    { $set: { "chain.$.balance": new_balance, } }
                );
                /// 找不到可更新的对象，改用插入
                console.log('updateRes', updateRes.result);
                if (updateRes.result.nModified === 0) {
                    const insertRes = await collection.updateOne(
                        { name: account.name },
                        // { $addToSet: { chain: { balance: new_balance, height: current_height } } }
                        // 不使用$addToSet来往后加，使用push来直接插入数组的前面，针对索引需求
                        {
                            $push: {
                                chain: {
                                    $each: [{ balance: new_balance, height: current_height }],
                                    $position: 0
                                }
                            }
                        }
                    );
                    console.log('insertRes', insertRes.result);
                }
                console.groupEnd(g, 'recode update/insert finished.');
                await sleep(1000);// 等待随机的时间，再进行下一次账户更新操作
            }
            return { name: account.name, records };
        }));
        console.log("UPDATE DONE.");
        // console.log(records_list);

        /* 4. 根据高度查询 */
        {
            /// 查询当前的余额，
            /* // 使用aggregate管道操作
                const cur_me = await collection.aggregate([
                { $match: { name: accounts[0].name } },
                { $project: { name: 1, chainItem: { $arrayElemAt: ["$chain", -1] } } },
                {
                    $project: { name: 1, balance: "$chainItem.balance", lastChangedHeight: "$chainItem.height" }
                }]); */
            const cur_me = await collection.find(
                {
                    name: accounts[0].name,
                },
                { projection: { chain: { $slice: 1 } } }
            );
            console.flag("cur round account info:", JSON.stringify(await cur_me.toArray()));

            const pre_me = await collection.find(
                {
                    name: accounts[0].name,
                    chain: { $elemMatch: { height: { $lt: current_round_start_height } } }
                },
                { projection: { 'chain.$': 1, name: 1 } }
            );
            console.flag("pre round account info:", JSON.stringify(await pre_me.toArray()));

        }

    } catch (err) {
        console.error(err)
    } finally {
        process.exit();
    }
});

round 1.log

START
CONNECTED
┌ [test0] [ 6211, 556 ]
│ ┌ [test1] [ 6211, 693 ]
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ insertRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ insertRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
┌ [test0] [ 6211, 532 ]
│ ┌ [test1] [ 6211, 849 ]
│ │ updateRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ updateRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
┌ [test0] [ 6212, 889 ]
│ ┌ [test1] [ 6212, 872 ]
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ insertRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ insertRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
┌ [test0] [ 6212, 918 ]
│ updateRes { n: 1, nModified: 1, ok: 1 }
└ recode update/insert finished.
┌ [test1] [ 6212, 63 ]
│ updateRes { n: 1, nModified: 1, ok: 1 }
└ recode update/insert finished.
┌ [test0] [ 6212, 811 ]
│ updateRes { n: 1, nModified: 1, ok: 1 }
└ recode update/insert finished.
┌ [test1] [ 6212, 800 ]
│ updateRes { n: 1, nModified: 1, ok: 1 }
└ recode update/insert finished.
UPDATE DONE.
[cur round account info:] [{"_id":"5afe91c4d4a30e1af449c5fa","name":"test0","chain":[{"balance":811,"height":6212}]}]
[pre round account info:] [{"_id":"5afe91c4d4a30e1af449c5fa","name":"test0","chain":[{"balance":0,"height":0}]}]

round 2.log

START
CONNECTED
┌ [test0] [ 6214, 693 ]
│ ┌ [test1] [ 6214, 844 ]
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ insertRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ insertRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
┌ [test0] [ 6215, 839 ]
│ ┌ [test1] [ 6215, 78 ]
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ insertRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ insertRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
┌ [test0] [ 6215, 138 ]
│ ┌ [test1] [ 6215, 677 ]
│ │ updateRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ updateRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
┌ [test0] [ 6216, 88 ]
│ ┌ [test1] [ 6216, 16 ]
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ updateRes { n: 0, nModified: 0, ok: 1 }
│ │ insertRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ insertRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
┌ [test0] [ 6216, 845 ]
│ ┌ [test1] [ 6216, 7 ]
│ │ updateRes { n: 1, nModified: 1, ok: 1 }
└─┼ recode update/insert finished.
  │ updateRes { n: 1, nModified: 1, ok: 1 }
  └ recode update/insert finished.
UPDATE DONE.
[cur round account info:] [{"_id":"5afe91c4d4a30e1af449c5fa","name":"test0","chain":[{"balance":845,"height":6216}]}]
[pre round account info:] [{"_id":"5afe91c4d4a30e1af449c5fa","name":"test0","chain":[{"balance":811,"height":6212}]}]