将Express Node.js项目部署到Azure 500服务器错误

Question

Seem to have tried every available solution even though some claim that Azure have fixed this issue internally, but I cannot get it to work, production deployment gives me a 500 error every time. Deploying locally works. Here's my app.js which is basically "out of the box" with express 4.12.2

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

var routes = require('./routes/index');
var users = require('./routes/users');

var app = express();

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

// uncomment after placing your favicon in /public
//app.use(favicon(__dirname + '/public/favicon.ico'));
app.set('port', process.env.PORT || 1337);
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', routes);
app.use('/users', users);

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

// error handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
  app.use(function(err, req, res, next) {
    res.status(err.status || 500);
    res.render('error', {
      message: err.message,
      error: err
    });
  });
}

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});


module.exports = app;

app.listen(app.get('port'), function(){
           console.log('Express server listening on port ' + app.get('port'));
           });

Answer 1

I suspect you might be getting this error in the logs.

Error: ENOENT, open 'D:\\home\\site\\wwwroot\\bin\\views\\layouts\\main.handlebars' at Error (native)

Enable the error logs

Note the path to the views folder.

You could try remove the www file. Check the last couple of paragraphs in the Express docs on how.

Also I found that adding app.use(express.static('public')); is needed if you have resources like images and fonts – it would fail silently otherwise.

Answer 2

Make sure that your entry point is in the root folder.

In my case, my entry point was './bin/www', I had to manually move this file to root and update the and sections in the Web.config to get it working.

Deploy again after making these changes.

Answer 3

there were a couple solutions provided in the following question

Azure NodeJS Error: ENOENT, open 'D:\\home\\site\\wwwroot\\bin\\views\\'

for now I simply used the following near the top of app.js process.chdir(__dirname);

Answer 4

I know it is very tricky to handle such scenarios.

1. Try to understand/google what versions of nodejs azure portal supports. It supports only specific versions. Note those versions and try to use any version you need or try using latest version only from that list.
2. In azure portal -> go to your app service -> you should see console in appservice details -> Type node -v.
3. This should give you node version may be like 0.10.4 or so. This may be the main main and main culprit.
4. Go to your app settings under configuration for your app service. Add node version there like WEBSITE_NODE_DEFAULT_VERSION as your node version ex: 8.9.4
5. Go to your package.json and add node version same as you used in azure portal appsettings. ex: "engines": { "node": "8.9.4" }
6. Restart app service -> check console -> node -v. if this shows same version then deploy application and it should work with out any issues.

---

How to check real errors instead of 500

1. In azure portal for your app service enable diagnostic logs
2. Select log stream
3. Refresh your site. Now you should see real error message in log stream.

Good luck.