api/app.ts

import Koa from 'koa'
import bodyParser from 'koa-bodyparser'
import logger from 'koa-logger'
import cors from '@koa/cors'
import serve from 'koa-static'
import path from 'path'
import fs from 'fs'
import { fileURLToPath } from 'url'
import systemRouter from './routes/system.js'
import dataRouter from './routes/data.js'

const __filename = fileURLToPath(import.meta.url)
const __dirname = path.dirname(__filename)

const app = new Koa()

// 中间件配置
app.use(cors())
app.use(logger())
app.use(bodyParser({
  jsonLimit: '10mb',
  formLimit: '10mb'
}))

// 错误处理
app.use(async (ctx, next) => {
  try {
    await next()
  } catch (err: unknown) {
    const error = err as { status?: number; message?: string }
    ctx.status = error.status || 500
    ctx.body = {
      success: false,
      error: error.message || '服务器内部错误'
    }
    ctx.app.emit('error', err, ctx)
  }
})

// 路由注册
app.use(systemRouter.routes()).use(systemRouter.allowedMethods())
app.use(dataRouter.routes()).use(dataRouter.allowedMethods())

// 生产环境下托管静态文件
if (process.env.NODE_ENV === 'production') {
  const distPath = path.resolve(__dirname, '../dist')
  app.use(serve(distPath))
  
  // 处理 SPA 路由
  app.use(async (ctx, next) => {
    if (ctx.status === 404 && !ctx.path.startsWith('/api')) {
      ctx.type = 'html'
      ctx.body = fs.readFileSync(path.join(distPath, 'index.html'))
    } else {
      await next()
    }
  })
}

// 404 处理
app.use(async (ctx) => {
  if (ctx.status === 404) {
    ctx.body = {
      success: false,
      error: '接口未找到'
    }
  }
})

export default app