如何开发一套EHS健康安全环境管理系统中的危废品管理板块？（附架构图+流程图+代码参考）

mermaid
flowchart TD
  A[产生危废] --> B[填写入库单（拍照+MSDS）]
  B --> C{审批}
  C -->|通过| D[入库，生成库存记录]
  C -->|驳回| E[通知产生人修改]
  D --> F[库存监控&看板]
  F --> G[出库申请（处置/外运）]
  G --> H{审批与承运确认}
  H -->|通过| I[出库，生成运输单]
  I --> J[处置单位处置并上传处置证明]
  J --> K[归档，更新处置率]
  K --> L[监管材料/报表导出]

css
[移动端/PC端] <---> [前端 App/SPA] <---> [API 网关] <---> [EHS 后端 (Express)] <---> [Postgres]
                                                          \
                                                           -> [对象存储 (MinIO/S3)] 
                                                           -> [消息队列 (RabbitMQ)]（告警/异步任务）
                                                           -> [第三方：处置公司系统/监管上报]

sql
-- db_schema.sql (Postgres)
CREATE TABLE users (
  id serial PRIMARY KEY,
  username varchar(64) UNIQUE NOT NULL,
  display_name varchar(128),
  role varchar(32),
  created_at timestamptz DEFAULT now()
);
CREATE TABLE waste_catalog (
  id serial PRIMARY KEY,
  code varchar(64) UNIQUE NOT NULL, -- 企业/国家编码
  name varchar(200) NOT NULL,
  category varchar(64), -- 易燃/腐蚀/有毒
  unit varchar(16) DEFAULT 'kg',
  msds_url text,
  storage_req text,
  created_at timestamptz DEFAULT now()
);
CREATE TABLE waste_batch (
  id serial PRIMARY KEY,
  batch_no varchar(64) UNIQUE NOT NULL,
  catalog_id int REFERENCES waste_catalog(id),
  quantity numeric(14,4) NOT NULL,
  unit varchar(16) DEFAULT 'kg',
  container_no varchar(64),
  location varchar(128),
  produced_by varchar(128),
  produced_at timestamptz,
  status varchar(32) DEFAULT 'IN_STOCK', -- IN_STOCK, OUT, DISPOSED
  created_at timestamptz DEFAULT now()
);
CREATE TABLE waste_inbound (
  id serial PRIMARY KEY,
  in_no varchar(64) UNIQUE NOT NULL,
  batch_id int REFERENCES waste_batch(id),
  catalog_id int REFERENCES waste_catalog(id),
  quantity numeric(14,4) NOT NULL,
  unit varchar(16),
  producer varchar(128),
  photos jsonb, -- [{url:, md5:}]
  approval_status varchar(32) DEFAULT 'PENDING', -- PENDING, APPROVED, REJECTED
  created_by int REFERENCES users(id),
  created_at timestamptz DEFAULT now()
);
CREATE TABLE waste_outbound (
  id serial PRIMARY KEY,
  out_no varchar(64) UNIQUE NOT NULL,
  batch_id int REFERENCES waste_batch(id),
  catalog_id int REFERENCES waste_catalog(id),
  quantity numeric(14,4) NOT NULL,
  to_company_id int REFERENCES waste_companies(id),
  transport_no varchar(128),
  approval_status varchar(32) DEFAULT 'PENDING',
  created_by int REFERENCES users(id),
  created_at timestamptz DEFAULT now()
);
CREATE TABLE waste_companies (
  id serial PRIMARY KEY,
  name varchar(256) NOT NULL,
  license_url text,
  contact_name varchar(128),
  contact_phone varchar(64),
  rating int DEFAULT 5,
  created_at timestamptz DEFAULT now()
);
CREATE TABLE attachments (
  id serial PRIMARY KEY,
  ref_table varchar(64),
  ref_id int,
  url text,
  md5 varchar(64),
  created_at timestamptz DEFAULT now()
);
CREATE TABLE approval_records (
  id serial PRIMARY KEY,
  ref_table varchar(64),
  ref_id int,
  approver_id int REFERENCES users(id),
  action varchar(32), -- APPROVE, REJECT
  comment text,
  created_at timestamptz DEFAULT now()
);
javascript
// backend/index.js (Node.js + Express + Knex)
const express = require('express');
const bodyParser = require('body-parser');
const Knex = require('knex');
const { v4: uuidv4 } = require('uuid');
const knex = Knex({
  client: 'pg',
  connection: process.env.DATABASE_URL || 'postgres://user:pass@localhost:5432/ehs'
});
const app = express();
app.use(bodyParser.json());
// util
function genNo(prefix='IN') {
  const t = new Date().toISOString().replace(/[-:T.]/g,'').slice(0,14);
  return `${prefix}${t}${Math.floor(Math.random()*900+100)}`;
}
// 1. 新建危废档案
app.post('/api/catalog', async (req, res) => {
  const { code, name, category, unit, msds_url, storage_req } = req.body;
  try {
    const [row] = await knex('waste_catalog').insert({
      code, name, category, unit, msds_url, storage_req
    }).returning('*');
    res.json({ success: true, data: row });
  } catch (err) {
    console.error(err);
    res.status(500).json({ success:false, message: err.message });
  }
});
// 2. 入库申请（含创建批次）
app.post('/api/inbound', async (req, res) => {
  const { catalog_id, quantity, unit, producer, produced_at, photos, created_by } = req.body;
  const trx = await knex.transaction();
  try {
    const batch_no = `BATCH-${Date.now()}-${Math.floor(Math.random()*900+100)}`;
    const [batch] = await trx('waste_batch').insert({
      batch_no, catalog_id, quantity, unit, produced_by: producer, produced_at
    }).returning('*');
    const in_no = genNo('IN');
    const [inRec] = await trx('waste_inbound').insert({
      in_no, batch_id: batch.id, catalog_id, quantity, unit, producer, photos: JSON.stringify(photos), created_by
    }).returning('*');
    await trx.commit();
    res.json({ success:true, data: { batch, inRec }});
  } catch (err) {
    await trx.rollback();
    console.error(err);
    res.status(500).json({ success:false, message: err.message });
  }
});
// 3. 审批入库（简单示例）
app.post('/api/inbound/:id/approve', async (req, res) => {
  const id = req.params.id;
  const { approver_id, action, comment } = req.body; // action: APPROVE/REJECT
  try {
    await knex.transaction(async trx => {
      await trx('waste_inbound').where({ id }).update({ approval_status: action==='APPROVE' ? 'APPROVED':'REJECTED' });
      await trx('approval_records').insert({
        ref_table: 'waste_inbound', ref_id: id, approver_id, action: action==='APPROVE'?'APPROVE':'REJECT', comment
      });
    });
    res.json({ success:true });
  } catch (err) {
    console.error(err);
    res.status(500).json({ success:false, message: err.message });
  }
});
// 4. 出库申请（并校验库存）
app.post('/api/outbound', async (req, res) => {
  const { batch_id, catalog_id, quantity, to_company_id, transport_no, created_by } = req.body;
  const trx = await knex.transaction();
  try {
    // 锁定批次数量
    const batch = await trx('waste_batch').where({ id: batch_id }).forUpdate().first();
    if (!batch) throw new Error('batch not found');
    if (parseFloat(batch.quantity) < parseFloat(quantity)) throw new Error('库存不足');
    // 插入出库记录（待审批）
    const out_no = genNo('OUT');
    const [outRec] = await trx('waste_outbound').insert({
      out_no, batch_id, catalog_id, quantity, to_company_id, transport_no, created_by
    }).returning('*');
    // 如果审批模型是自动直接减库存，则在审批通过时减库存。这里只是示例：不做减库存
    await trx.commit();
    res.json({ success:true, data: outRec });
  } catch (err) {
    await trx.rollback();
    console.error(err);
    res.status(500).json({ success:false, message: err.message });
  }
});
// 5. 出库审批通过，真正扣减库存并生成处置记录
app.post('/api/outbound/:id/approve', async (req, res) => {
  const id = req.params.id;
  const { approver_id, action, comment } = req.body;
  try {
    await knex.transaction(async trx => {
      const outRec = await trx('waste_outbound').where({ id }).first();
      if (!outRec) throw new Error('outbound not found');
      if (action !== 'APPROVE') {
        await trx('waste_outbound').where({ id }).update({ approval_status: 'REJECTED' });
      } else {
        // 扣减批次数量
        const batch = await trx('waste_batch').where({ id: outRec.batch_id }).forUpdate().first();
        const newQty = parseFloat(batch.quantity) - parseFloat(outRec.quantity);
        await trx('waste_batch').where({ id: batch.id }).update({
          quantity: newQty,
          status: newQty <= 0 ? 'OUT' : batch.status
        });
        await trx('waste_outbound').where({ id }).update({ approval_status: 'APPROVED' });
      }
      await trx('approval_records').insert({
        ref_table: 'waste_outbound', ref_id: id, approver_id, action: action==='APPROVE'?'APPROVE':'REJECT', comment
      });
    });
    res.json({ success:true });
  } catch (err) {
    console.error(err);
    res.status(500).json({ success:false, message: err.message });
  }
});
app.get('/api/dashboard/summary', async (req, res) => {
  // 简单看板示例
  const totals = await knex('waste_batch').select(
    knex.raw('count(*) as batch_count'),
    knex.raw('sum(quantity) as total_qty')
  ).first();
  // 超期示例（假设 produced_at + 30 days 为超期）
  const overdue = await knex('waste_batch').whereRaw("produced_at < now() - interval '30 days'").count();
  res.json({ success:true, data: { totals, overdue: parseInt(overdue[0].count || 0) }});
});
const PORT = process.env.PORT || 3000;
app.listen(PORT, ()=> console.log('server running', PORT));
jsx
// 前端 React 关键片段（入库表单 + 看板请求）
import React, { useState } from 'react';
function InboundForm({ userId }) {
  const [catalogId, setCatalogId] = useState('');
  const [quantity, setQuantity] = useState('');
  const [producer, setProducer] = useState('');
  const [photos, setPhotos] = useState([]);
  async function uploadPhoto(file) {
    // 简化：假设后端有 /api/upload 返回 {url}
    const fd = new FormData();
    fd.append('file', file);
    const r = await fetch('/api/upload', { method:'POST', body:fd });
    const j = await r.json();
    return j.url;
  }
  async function handleSubmit(e) {
    e.preventDefault();
    const photoUrls = [];
    for (const f of photos) {
      const url = await uploadPhoto(f);
      photoUrls.push({ url });
    }
    const payload = {
      catalog_id: catalogId,
      quantity,
      unit: 'kg',
      producer,
      produced_at: new Date().toISOString(),
      photos: photoUrls,
      created_by: userId
    };
    const res = await fetch('/api/inbound', {
      method:'POST',
      headers: {'Content-Type':'application/json'},
      body: JSON.stringify(payload)
    });
    const data = await res.json();
    if (data.success) {
      alert('入库申请已提交');
    } else {
      alert('提交失败：' + data.message);
    }
  }
  return (
    <form onSubmit={handleSubmit}>
      <label>危废类型ID：<input value={catalogId} onChange={e=>setCatalogId(e.target.value)} /></label><br/>
      <label>数量：<input value={quantity} onChange={e=>setQuantity(e.target.value)} /></label><br/>
      <label>产生单位/人：<input value={producer} onChange={e=>setProducer(e.target.value)} /></label><br/>
      <label>照片：<input type="file" multiple onChange={e=>setPhotos(Array.from(e.target.files))} /></label><br/>
      <button type="submit">提交入库申请</button>
    </form>
  );
}
export default function Dashboard() {
  const [summary, setSummary] = useState(null);
  React.useEffect(()=> {
    fetch('/api/dashboard/summary').then(r=>r.json()).then(j=> setSummary(j.data));
  }, []);
  if (!summary) return <div>加载中...</div>;
  return (
    <div>
      <h3>看板</h3>
      <div>批次数量：{summary.totals.batch_count}</div>
      <div>总库存：{summary.totals.total_qty}</div>
      <div>超期批次：{summary.overdue}</div>
    </div>
  );
}