如何开发ERP（离散制造-MTO）系统中的销售管理板块（附架构图+流程图+代码参考）

+------------------------------------------------------------+
| 客户/销售前端 (Web/移动/自助门户)                          |
+-----------------------------+------------------------------+
                              |
                API 网关（鉴权、限流、统一日志、API 版本） 
                              |
+-----------+--------+-------+---------+---------------------+
| Sales Svc | Pricing| Inv Svc| Scheduler | Integration Svc |
| (quotes,  | Svc    | (stock,| (MRP/APS) | (MES/财务/CRM)  |
| orders)   | rules  | ATP)   |           |                 |
+-----------+--------+-------+---------+---------------------+
       |               |         |           |
       +---------------+---------+-----------+
                       |
                 事件总线（Kafka / RabbitMQ / Redis Stream）
                       |
                支撑服务：采购、仓库、排产、质检、财务

后端：server.js（简化）
// server.js
const express = require('express');
const bodyParser = require('body-parser');
const { Pool } = require('pg');
const EventEmitter = require('events');
const bus = new EventEmitter();
const pool = new Pool({
  host: process.env.PG_HOST || 'localhost',
  user: process.env.PG_USER || 'postgres',
  password: process.env.PG_PASS || 'password',
  database: process.env.PG_DB || 'erp',
  port: process.env.PG_PORT || 5432,
});
const app = express();
app.use(bodyParser.json());
// 创建报价
app.post('/api/quotes', async (req, res) => {
  const { customer_id, items, valid_until } = req.body;
  const client = await pool.connect();
  try {
    await client.query('BEGIN');
    const r = await client.query(
      `INSERT INTO quotes (customer_id, status, total_amount, valid_until) VALUES ($1,$2,$3,$4) RETURNING id`,
      [customer_id, 'DRAFT', 0, valid_until]
    );
    const quoteId = r.rows[0].id;
    // items 是 [{product_id, qty, unit_price}]
    for (const it of items) {
      await client.query(
        `INSERT INTO quote_lines (quote_id, product_id, qty, unit_price, line_amount) VALUES ($1,$2,$3,$4,$5)`,
        [quoteId, it.product_id, it.qty, it.unit_price, it.qty * it.unit_price]
      );
    }
    // 简单计算 total
    const t = await client.query(`SELECT SUM(line_amount) as total FROM quote_lines WHERE quote_id=$1`, [quoteId]);
    await client.query(`UPDATE quotes SET total_amount=$1 WHERE id=$2`, [t.rows[0].total || 0, quoteId]);
    await client.query('COMMIT');
    res.status(201).json({ id: quoteId });
  } catch (err) {
    await client.query('ROLLBACK');
    console.error(err);
    res.status(500).send('error');
  } finally {
    client.release();
  }
});
// 报价确认 -> 生成订单并发布事件
app.post('/api/quotes/:id/confirm', async (req, res) => {
  const quoteId = req.params.id;
  const client = await pool.connect();
  try {
    await client.query('BEGIN');
    const q = await client.query(`SELECT * FROM quotes WHERE id=$1 FOR UPDATE`, [quoteId]);
    if (q.rowCount === 0) return res.status(404).send('quote not found');
    const quote = q.rows[0];
    if (quote.status !== 'DRAFT') return res.status(400).send('invalid status');
    const ord = await client.query(
      `INSERT INTO sales_orders (quote_id, customer_id, status, order_date, total_amount) VALUES ($1,$2,$3,$4,$5) RETURNING id`,
      [quoteId, quote.customer_id, 'NEW', new Date(), quote.total_amount]
    );
    const orderId = ord.rows[0].id;
    // copy lines
    const lines = await client.query(`SELECT product_id, qty, unit_price FROM quote_lines WHERE quote_id=$1`, [quoteId]);
    for (const ln of lines.rows) {
      await client.query(
        `INSERT INTO order_lines (order_id, product_id, qty, unit_price, status) VALUES ($1,$2,$3,$4,$5)`,
        [orderId, ln.product_id, ln.qty, ln.unit_price, 'NEW']
      );
    }
    await client.query(`UPDATE quotes SET status='CONFIRMED' WHERE id=$1`, [quoteId]);
    await client.query('COMMIT');
    // 发布事件（事务外）
    bus.emit('order.created', { orderId });
    res.json({ ok: true, orderId });
  } catch (err) {
    await client.query('ROLLBACK');
    console.error(err);
    res.status(500).send('error');
  } finally {
    client.release();
  }
});
// 监听 order.created 并尝试锁库存（示例）
bus.on('order.created', async (payload) => {
  console.log('event order.created', payload);
  // 这里实际应调用库存服务 API 或发送消息到队列
  // 简单示例：读取订单行并标记 reserve（伪操作）
  const client = await pool.connect();
  try {
    const lines = await client.query(`SELECT product_id, qty FROM order_lines WHERE order_id=$1`, [payload.orderId]);
    for (const ln of lines.rows) {
      // 伪逻辑：插入 stock_moves 表当作锁定请求
      await client.query(
        `INSERT INTO stock_moves (type, ref_id, product_id, qty, from_loc, to_loc, status) VALUES ($1,$2,$3,$4,$5,$6,$7)`,
        ['reserve', payload.orderId, ln.product_id, ln.qty, 'WH:MAIN', 'RESERVE', 'PENDING']
      );
    }
    // 这里可触发异步任务处理实际库存扣减
  } catch (err) {
    console.error(err);
  } finally {
    client.release();
  }
});
app.listen(3000, () => console.log('listening 3000'));

CREATE TABLE customers (id serial PRIMARY KEY, code text UNIQUE, name text);
CREATE TABLE products (id serial PRIMARY KEY, sku text UNIQUE, name text, lead_time_days int);
CREATE TABLE quotes (id serial PRIMARY KEY, quote_no text, customer_id int references customers(id), status text, total_amount numeric, valid_until date);
CREATE TABLE quote_lines (id serial PRIMARY KEY, quote_id int references quotes(id), product_id int references products(id), qty numeric, unit_price numeric, line_amount numeric);
CREATE TABLE sales_orders (id serial PRIMARY KEY, order_no text, quote_id int references quotes(id), customer_id int references customers(id), status text, order_date timestamp, total_amount numeric);
CREATE TABLE order_lines (id serial PRIMARY KEY, order_id int references sales_orders(id), product_id int references products(id), qty numeric, unit_price numeric, status text);
CREATE TABLE stock_moves (id serial PRIMARY KEY, type text, ref_id int, product_id int references products(id), qty numeric, from_loc text, to_loc text, status text);

// QuoteForm.jsx
import React, { useState } from 'react';
import axios from 'axios';
export default function QuoteForm(){
  const [items, setItems] = useState([{ product_id:1, qty:1, unit_price:100 }]);
  async function createQuote(){
    const res = await axios.post('/api/quotes', { customer_id:1, items, valid_until: '2025-12-31' });
    alert('报价创建 ID: ' + res.data.id);
  }
  async function confirmQuote(id){
    const res = await axios.post(`/api/quotes/${id}/confirm`);
    alert('已确认，订单ID: ' + res.data.orderId);
  }
  return (
    <div>
      <h3>报价（示例）</h3>
      <button onClick={createQuote}>创建报价</button>
      <button onClick={() => confirmQuote(1)}>确认报价ID=1（示例）</button>
    </div>
  );
}