app.js

const express = require('express');
const path = require('path');
const favicon = require('serve-favicon');
const logger = require('morgan');
const cookieParser = require('cookie-parser');
const bodyParser = require('body-parser');
const compression = require('compression');

const posts = require('./routes/posts');

const app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'pug');

// server side set the headers information of reponse to support cross orign resource sharing(CORS)(get,post).

// app.all('*', function (req, res, next) {
//     res.header('Access-Control-Allow-Origin', '*');
//     res.header(
//         'Access-Control-Allow-Headers',
//         'Origin, X-Requested-With, Content-Type, Accept, Connection, User-Agent, Cookie'
//     );
//     res.header('Access-Control-Allow-Methods', 'PUT,POST,GET,DELETE,OPTIONS');
//     res.header('X-Powered-By', ' 3.2.1');
//     res.header('Content-Type', 'application/json;charset=utf-8');
//     next();
// });

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(compression());
app.use(logger('dev'));
app.use(
    bodyParser.json({
        limit: '1mb'
    })
);
app.use(
    bodyParser.urlencoded({
        extended: false
    })
);
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use(express.static(path.join(__dirname, 'upload')));

app.use('/posts', posts);

// catch 404 and forward to error handler
app.use(function (req, res, next) {
    const err = new Error('Not Found');
    err.status = 404;
    next(err);
});

app.use(function (err, req, res, next) {
    // 设置响应状态
    res.status(err.status || 500);
    // 渲染错误处理页
    res.json({
        message: err.message,
        error: err
    });
});

module.exports = app;