bm-scaffold-test/lib/middleware/proxy.js

本木前端脚手架

/**
 * @Author: songqi
 * @Date:   2016-07-15
 * @Email:  songqi@benmu-health.com
 * @Last modified by:   songqi
 * @Last modified time: 2016-11-10
 */

var fs = require('fs'),
    url = require('url'),
    _ = require('lodash'),
    path = require('path'),
    http = require('http'),
    https = require('https'),
    readConfig = require('../../utils/readConfig');

function proxyRequest(request, response, next) {
    var target = request.target ? request.target + '/' : '';
    if (request.client.ssl) {
        var options = url.parse('https://' + target + request.url.slice(1));
        options['rejectUnauthorized'] = false;
        https.request(options, function(remoteRequest) {
            if (remoteRequest.statusCode === 200) {
                response.setHeader('Content-Type', remoteRequest.headers['content-type']);
                remoteRequest.pipe(response);
            } else {
                response.writeHead(remoteRequest.statusCode);
                response.end();
            }
        }).on('error', function(e) {
            next();
        }).end();
    } else {
        var options = url.parse('http://' + target + request.url.slice(1));
        http.request(options, function(remoteRequest) {
            if (remoteRequest.statusCode === 200) {
                response.setHeader('Content-Type', remoteRequest.headers['content-type']);
                remoteRequest.pipe(response);
            } else {
                response.writeHead(remoteRequest.statusCode);
                response.end();
            }
        }).on('error', function(e) {
            next();
        }).end();
    }

};

function testProxy(request, proxyConfig) {
    if (request.url.slice(0, proxyConfig.route.length) === proxyConfig.route) {
        request.url = request.url.slice(proxyConfig.route.length);
        proxyConfig.target && (request.target = proxyConfig.target);
        return request;
    } else {
        return false;
    }
}

function Proxy(options) {

    var config = _.assign({
        root: path.join(process.cwd(), '../'),
        proxy: ''
    }, {
        proxy: readConfig.get('proxy')
    });

    return function(request, response, next) {
        if (!config.proxy || _.isArray(config.proxy) && !config.proxy.length) {
            next();
            return;
        }

        if (typeof config.root === 'string') {
            config.root = [config.root]
        } else if (!_.isArray(config.root)) {
            throw new Error('No root specified')
        }

        var pathChecks = [];
        config.root.forEach(function(root, i) {
            var _isProxy = false,
                _proxy = false,
                p = path.resolve(root) + request.url;
            fs.access(p, function(err) {
                pathChecks.push(err ? false : true);
                if (config.root.length == ++i) {
                    var pathExists = pathChecks.some(function(p) {
                        return p;
                    });
                    if (pathExists) {
                        next();
                    } else {
                        if (_.isArray(config.proxy)) {
                            _isProxy = config.proxy.some(function(item) {
                                _proxy = testProxy(request, item);
                                if (_proxy) {
                                    proxyRequest(_proxy, response, next);
                                    return true
                                }
                            })
                            if (!_isProxy) {
                                next();
                            }
                        } else if (config.proxy && config.proxy.route) {
                            _proxy = testProxy(request, config.proxy);
                            if (_proxy) {
                                proxyRequest(_proxy, response, next);
                            } else {
                                next();
                            }
                        } else {
                            next();
                        }
                    }
                }
            });
        })
    }
}

module.exports = Proxy