index.js

'use strict';

const startTime = new Date();

const Koa = require('koa');
const hbs = require('koa-hbs');
const conditional = require('koa-conditional-get');
const etag = require('koa-etag');
const send = require('koa-send');
const serve = require('koa-static');
const router = require('koa-router')();
const bodyParser = require('koa-bodyparser');

const initConfig = require('./init/config');
const initMongoose = require('./init/mongoose');

// 初始化配置
global.config = initConfig.init();

// 初始化 Mongoose
initMongoose.init().catch(err => console.error(err.stack));

const app = new Koa();

// 异常处理
app.use(async (ctx, next) => {
  try {
    await next();
    if (!ctx.status || ctx.status === 404) {
      ctx.throw(404);
    }
  } catch (err) {
    ctx.status = parseInt(err.status) || 500;
    switch (ctx.status) {
    case 404:
      await send(ctx, 'public/404.html');       // __dirname + ... 是无效的
      break;

    case 400:
      break;

    case 500:
    default:
      await send(ctx, 'public/500.html');
      break;
    }
  }
});

// 设置调试日志
if (process.env.NODE_ENV === 'development') {
  app.use(require('koa-logger')());
}

// 设置 etag
app.use(conditional());
app.use(etag({ weak: true }));

// 嘻嘻…
app.use(async (ctx, next) => {
  ctx.set('X-Powered-By', 'Koa');
  await next();
});

// 设置模板引擎
app.use(hbs.middleware({
  viewPath: __dirname + '/views',
  defaultLayout: 'layout',
  partialsPath: __dirname + '/views/partials',
}));

// 静态资源
app.use(serve(__dirname + '/public'));

// Body parser
app.use(bodyParser());

// 设置路由
const index = require('./routes/index');
const users = require('./routes/users');
const api = require('./routes/api');
router.use('/', index.routes(), index.allowedMethods());
router.use('/users', users.routes(), users.allowedMethods());
router.use('/api', api.routes(), api.allowedMethods());
app.use(router.routes(), router.allowedMethods());

app.startUp = () => app.listen(global.config.system, () => {
  console.log('\x1b[90mServer started up in \x1b[1;36m%d\x1b[90m ms. ' +
              'Environment is \x1b[1;36m%s\x1b[90m. ' +
              'Address: \x1b[1;36mhttp://%s:%s\x1b[0m',
              new Date() - startTime,
              process.env.NODE_ENV,
              global.config.system.host,
              global.config.system.port);
});

module.exports = app;