Why do I obtain this error when deploying app to Heroku?

Question

I am getting some kind of error when deploying my app to heroku using git hub. The problem is, I don't understand the heroku logs and the entailing errors. Here is the heroku log:

Marcuss-MacBook-Pro:Weather-App marcushurney$ heroku logs
2016-01-05T14:37:27.798077+00:00 app[web.1]: npm ERR! Please include the following file with any support request:
2016-01-05T14:37:27.798377+00:00 app[web.1]: npm ERR!     /app/npm-debug.log
2016-01-05T14:37:27.786949+00:00 app[web.1]: npm ERR! node v5.1.1
2016-01-05T14:37:27.786556+00:00 app[web.1]: npm ERR! argv "/app/.heroku/node/bin/node" "/app/.heroku/node/bin/npm" "start"
2016-01-05T14:37:27.787856+00:00 app[web.1]: npm ERR! npm  v3.3.12
2016-01-05T14:37:28.776245+00:00 heroku[web.1]: Process exited with status 1
2016-01-05T14:37:28.789412+00:00 heroku[web.1]: State changed from starting to crashed
2016-01-05T17:27:16.684869+00:00 heroku[web.1]: State changed from crashed to starting
2016-01-05T17:27:17.853743+00:00 heroku[web.1]: Starting process with command `npm start`
2016-01-05T17:27:20.423495+00:00 app[web.1]: npm ERR! node v5.1.1
2016-01-05T17:27:20.423130+00:00 app[web.1]: npm ERR! argv "/app/.heroku/node/bin/node" "/app/.heroku/node/bin/npm" "start"
2016-01-05T17:27:20.424111+00:00 app[web.1]: npm ERR! npm  v3.3.12
2016-01-05T17:27:20.425937+00:00 app[web.1]: npm ERR! missing script: start
2016-01-05T17:27:20.422441+00:00 app[web.1]: npm ERR! Linux 3.13.0-71-generic
2016-01-05T17:27:20.426242+00:00 app[web.1]: npm ERR! 
2016-01-05T17:27:20.426432+00:00 app[web.1]: npm ERR! If you need help, you may report this error at:
2016-01-05T17:27:20.426634+00:00 app[web.1]: npm ERR!     <https://github.com/npm/npm/issues>

Answer 1

You have to inform heroku where to start : missing script: start. In your package.json, you should have something like this:

"scripts": {
  "start": "node index.js"
}

Where index.js is your entry point.

As an alternative, you can specify in Procfile:

web: node index.js

How to use both

If you still want to use the start script from within the Procfile:

web: npm start

In this case, you can still feature your start script from the package.json file as it is the usual way to proceed and it will be taken into account by Heroku.

Answer 2

My silly mistake was that I was pushing the master branch to Heroku while my changes were in another branch!

Make sure that you merge your latest branch with your master branch first

> git checkout master

> git merge your-latest-branch

> git push heroku master