Express.js强制HTTPS/SSL重定向错误：重定向太多

Question

所以堆栈如下：Express & Angular部署到Heroku。我正试图通过使用下面突出显示的代码进行简单重定向来强制通过HTTPS为应用提供服务。但是，当我在浏览器中打开URL时，出现“重定向太多”的错误。

当我输入http://[myurl].com时，我可以在浏览器中看到更改为https://[myurl].com的URL，但没有在该地址显示。它只是显示'太多重定向'。这证明它成功地重定向了，但我觉得Angular会搞砸它。

当我删除下面的重定向代码并在浏览器中手动访问HTTPS或HTTP地址时，它工作正常。

//HTTPS redirect middleware 
function ensureSecure(req, res, next) { 
    console.log(req.protocol + process.env.PORT + '' + req.hostname + req.url); 
    if(req.secure || req.hostname=='localhost'){ 
     //Secure request, continue to next middleware 
     next(); 
    }else{ 
     res.redirect('https://' + req.hostname + req.url); 
     console.log(req.protocol + process.env.PORT + '' + req.hostname + req.url); 
    } 
} 
//Parse the body of the request as a JSON object, part of the middleware stack (https://www.npmjs.com/package/body-parser#bodyparserjsonoptions) 
app.use(bodyParser.json()); 
//Serve static Angular JS assets from distribution, part of the middleware stack, but only through HTTPS 
app.all('*', ensureSecure); 
app.use('/', express.static('dist')); 
//Import routes 
app.use('/api', [router_getToken, router_invokeBhApi]); 
//Setup port for access 
app.listen(process.env.PORT || 3000, function() { 
    console.log(`The server is running on port ${process.env.PORT || 3000}!`); 
}); 

这是Heroku的日志的样本，当您访问http://[myurl].com（我屏蔽的网址）：

2016-11-29T21:50:34.363391+00:00 app[web.1]: 0|app  | http37436[something].com/ 
2016-11-29T21:50:34.363468+00:00 app[web.1]: 0|app  | http37436[something].com/ 
2016-11-29T21:50:34.402022+00:00 app[web.1]: 0|app  | http37436[something].com/ 
2016-11-29T21:50:34.402091+00:00 app[web.1]: 0|app  | http37436[something].com/ 
2016-11-29T21:50:34.436006+00:00 app[web.1]: 0|app  | http37436[something].com/ 
2016-11-29T21:50:34.437454+00:00 app[web.1]: 0|app  | http37436[something].com/ 
2016-11-29T21:50:34.479580+00:00 app[web.1]: 0|app  | http37436[something].com/ 

的浏览器（Chrome最新）显示在网络选项卡上&这些请求在&一遍又一遍：
'请求URL：https://[myurl].com/
请求方法：GET
状态代码：302找到'

注意Heroku（express.js代码中的console.log）如何显示我正在发出HTTP请求，但我的浏览器正在说我正在发出HTTPS请求。如此迷茫！

编辑： 我想这也

//HTTPS redirect middleware 
function ensureSecure(req, res, next) { 
    console.log(req.protocol + process.env.PORT + '' + req.hostname + req.url); 
    if (req.secure || req.hostname == 'localhost') { 
     //Serve Angular App 
     express.static('dist'); 
    } else { 
     //res.redirect('https://' + req.hostname + ':' + process.env.PORT + req.url); 
     res.redirect('https://[myurl].com/'); 
    } 
} 
//Parse the body of the request as a JSON object, part of the middleware stack (https://www.npmjs.com/package/body-parser#bodyparserjsonoptions) 
app.use(bodyParser.json()); 
//Serve static Angular JS assets from distribution, part of the middleware stack, but only through HTTPS 
app.use('/', ensureSecure); 
//Import routes 
app.use('/api', [router_getToken, router_invokeBhApi]); 
//Setup port for access 
app.listen(process.env.PORT || 3000, function() { 
    console.log(`The server is running on port ${process.env.PORT || 3000}!`); 
}); 

Answer 1

找到了解决办法！

上下文：Heroku将原始协议存储在名为“X-Forwarded-Proto”的标头变量中。 HTTP Routing in Heroku您需要检查这个变量，而不是绑定到Express中'req'对象的协议变量。 （也就是说，不检查req.protocol，检查req.get（ 'X - 转发，原'）代替）

代码：

//HTTPS redirect middleware 
function ensureSecure(req, res, next) { 
    //Heroku stores the origin protocol in a header variable. The app itself is isolated within the dyno and all request objects have an HTTP protocol. 
    if (req.get('X-Forwarded-Proto')=='https' || req.hostname == 'localhost') { 
     //Serve Angular App by passing control to the next middleware 
     next(); 
    } else if(req.get('X-Forwarded-Proto')!='https' && req.get('X-Forwarded-Port')!='443'){ 
     //Redirect if not HTTP with original request URL 
     res.redirect('https://' + req.hostname + req.url); 
    } 
}