I get the following error after deploying my Yeoman app to Heroku
GET http://myapp.herokuapp.com/favicon.ico 503 (Service Unavailable)
I have a favicon image, and everything runs fine locally with the favicon image appearing. I'm not sure how to fix this error or why it is being caused in the first place.
Here is all my code: https://github.com/dkretsch12/MyHerokuApp
And I push it to Heroku with the following commands:
git add .
git commit -am "still stuck"
git push heroku master
I also ran into this, and for me it turned out the '503 (Service Unavailable)' error was not the real error.
Try:
heroku logs --app [your-app-name]
and see if it gives you more info.
In my case it was that Heroku was looking for npm start script, which I had not specified, but is required by Heroku. Looking at your package.json I see you don't have it either, so that might be the place to start.
edit
I think the underlying reason for this error is that by default Heroku expects a webserver or some kind executable to be running in the background. It's needed because otherwise incoming requests would not be handled. So it has to be provided by the programmer, and after installation Heroku will run it, either by npm start or by what is specified in the Procfile.
I my case I needed a webserver anyway, so I just created a server.js module where I implemented a small express app. Then in package.json I specified:
"scripts": {
"start": "node server.js",
...
},
But this may not be the right solution for you, it depends on what you want with your app. I don't know anything about Grunt or Angular, so I can't help you there. I did find this question which may be of value to you. I also recommend reading the docs on Heroku Dev Center