MongoDB not connecting to Heroku? Application Error - node.js

Question

I tested it out using npm modules: "node-dev" on the backend.js and "serve" on the root directory of the folder.
I have these 2 guides that tried to help me:
http://www.tilcode.com/deploying-a-mean-stack-app-to-heroku/
and another one from scotch.io "Use MongoDB with a Node.js Application on Heroku"
What I didn't do from the articles that shouldn't matter: in tilcode, it said use to github to generate an SSH key...instead I made one using my mac and a terminal command using some guide.
To summarize my steps:
Login to heroku, create the app
use git commands to add, commit all the files in my github into heroku and pushed them into heroku
I even put the mlab addon and filled out the URI.
It deployed "successfully" but when visiting the app, it says "application failed"
My suspicions:
I do have another working app that uses postgreSQL...but I put it on 'maintenance mode' since my free account only allows for one active dynamo.
Instead of uploading all my node modules, I learned I could have heroku install it like this:
heroku config:set NPM_CONFIG_PRODUCTION=false
I think it may be how I referenced the backend from my frontend javascript.
// var API = 'http://localhost:5000';
var API = 'http://limitless-falls-21423.herokuapp.com';
var app = angular.module('HAL-app', ['ngRoute', 'ngCookies']);
// Some other stuff that came from sandbox app.js
app.directive('whenScrolled', function() {
return function(scope, elm, attr) {
var raw = elm[0];
elm.bind('scroll', function() {
if (raw.scrollTop + raw.offsetHeight >= raw.scrollHeight) {
scope.$apply(attr.whenScrolled);
}
});
};
});
Lastly, when I ran heroku logs --tail I got these messages:
2016-09-05T01:35:27.417956+00:00 app[web.1]: npm ERR! Linux 3.13.0-93-generic
2016-09-05T01:35:27.418339+00:00 app[web.1]: npm ERR! argv "/app/.heroku/node/bin/node" "/app/.heroku/node/bin/npm" "start"
2016-09-05T01:35:27.418593+00:00 app[web.1]: npm ERR! node v5.11.1
2016-09-05T01:35:27.418931+00:00 app[web.1]: npm ERR! npm v3.8.6
2016-09-05T01:35:27.419219+00:00 app[web.1]: npm ERR! code ELIFECYCLE
2016-09-05T01:35:27.419386+00:00 app[web.1]: npm ERR! hallocam#1.0.0 start:
node backend.js
2016-09-05T01:35:37.178679+00:00 heroku[router]: at=error code=H10 desc="App crashed" method=GET path="/" host=limitless-falls-21423.herokuapp.com request_id=4bc9639f-3f64-4c0b-9b0d-d99b967f1b36 fwd="73.54.129.252" dyno= connect= service= status=503 bytes=
******EDIT after Yashua's comment**
I now get a "cannot get" message when visiting the app. Was kinda hesitant about limiting my heroku variables to just the:
NODE_ENV=production
But I guess it makes since since if I keep my mongodb (mongo labs) credentials uploaded and hidden using .gitignore.
Anyway, I'm still thinking it's not "getting" my routes which I have setup my angularjs file like this:
// var API = 'http://localhost:5000'; ##this is the old way to connect my front end factory routes to the backend hosted on 5000
I have it like this right now
var API = 'http://obscure-brook-35938.herokuapp.com/';
I think it may have to look like this:
var API = process.env.PORT
The purpose of the API is to be used for my angular factories like this:
app.factory('backEnd', function($http) {
return {
getSignUp: function(data) {
return $http({
method: 'POST',
url: API + '/signup',
data: data
});
},
getLogin: function(data) {
return $http({
method: 'POST',
url: API + '/login',
data: data
});
},
New Heroku logs --tail
2016-09-05T15:42:52.796464+00:00 heroku[router]: at=info method=GET path="/" host=obscure-brook-35938.herokuapp.com request_id=41fa32e2-42cc-426d-a0d0-ef6755329497 fwd="73.54.129.252" dyno=web.1 connect=1ms service=18ms status=404 bytes=243
2016-09-05T15:42:53.893156+00:00 heroku[router]: at=info method=GET path="/" host=obscure-brook-35938.herokuapp.com request_id=dec235fd-6d54-42e6-b0cc-2f83920d500d fwd="73.54.129.252" dyno=web.1 connect=1ms service=8ms status=404 bytes=243
2016-09-05T15:42:54.602312+00:00 heroku[router]: at=info method=GET path="/" host=obscure-brook-35938.herokuapp.com request_id=8ceb054b-78e9-49b8-bdee-286ca6efcb0d fwd="73.54.129.252" dyno=web.1 connect=1ms service=3ms status=404 bytes=243

Answer 1

Hard to tell offhand but here are some pointers:
I looked at your repo and your package.json is invalid in 2 places. Use a JSON validator.
Secondly your frontend app will not be an issue. You should be able to go to the server URL directly and not have it crashed.
Change your database password if you haven't already. I see that you deleted your mongo_creds.json file but the history is available on GitHub.
The only vars you should need on Heroku is NODE_CONFIG set to production.

Answer 2

I'm closing this thread because it's getting pretty lengthy and a separate problem has arose. As #yashua said, the best way to solve this mongodb/heroku problems is to take it one step at a time. Some tools I've learned from this experience:
If using NPMs to test, that's great as it builds confidence. But to truly test heroku, use its 'heroku local' or 'heroku local web' to test it out locally first (serve it up), then it'll help narrow down further issues when deploying/'git push heroku master'
Build a solid understanding of how .env files work (really, they're
just configuration files to store credential information). I've been
using .json files to store mine, then use .gitignore to stop them
from appearing publicly. Heroku has its own secret keepers in the
form of Procfile and .env
I'm up to a point now where I consolidated my backend/frontend into one root directory. But my frontend and backend use 2 different ports to work when it should only use one. Not sure the best way to approach that since when I do [supposedly] feed them all the same port as 'process.env.MONGOLAB_URI' I get an error that hints that I have it wrong.
2016-09-05T23:36:51.802697+00:00 app[web.1]: /app/node_modules/mongodb/lib/server.js:261
2016-09-05T23:36:51.802698+00:00 app[web.1]: process.nextTick(function() { throw err; })
2016-09-05T23:36:51.802698+00:00 app[web.1]: ^
2016-09-05T23:36:51.803862+00:00 app[web.1]: MongoError: failed to connect to server [#:27017] on first connect
2016-09-05T23:36:51.803864+00:00 app[web.1]: at Pool.<anonymous> (/app/node_modules/mongodb-core/lib/topologies/server.js:313:35)
2016-09-05T23:36:51.803864+00:00 app[web.1]: at emitOne (events.js:96:13)
2016-09-05T23:36:51.803865+00:00 app[web.1]: at Pool.emit (events.js:188:7)
2016-09-05T23:36:51.803865+00:00 app[web.1]: at Connection.<anonymous> (/app/node_modules/mongodb-core/lib/connection/pool.js:260:12)
2016-09-05T23:36:51.803866+00:00 app[web.1]: at Connection.g (events.js:286:16)
2016-09-05T23:36:51.803867+00:00 app[web.1]: at emitTwo (events.js:106:13)
2016-09-05T23:36:51.803867+00:00 app[web.1]: at Connection.emit (events.js:191:7)
2016-09-05T23:36:51.803868+00:00 app[web.1]: at Socket.<anonymous> (/app/node_modules/mongodb-core/lib/connection/connection.js:162:49)
2016-09-05T23:36:51.803868+00:00 app[web.1]: at Socket.g (events.js:286:16)
2016-09-05T23:36:51.803869+00:00 app[web.1]: at emitOne (events.js:96:13)
2016-09-05T23:36:51.803870+00:00 app[web.1]: at Socket.emit (events.js:188:7)
2016-09-05T23:36:51.803870+00:00 app[web.1]: at connectErrorNT (net.js:1016:8)
2016-09-05T23:36:51.803871+00:00 app[web.1]: at _combinedTickCallback (internal/process/next_tick.js:74:11)
2016-09-05T23:36:51.803871+00:00 app[web.1]: at process._tickCallback (internal/process/next_tick.js:98:9)
2016-09-05T23:36:51.881752+00:00 heroku[web.1]: State changed from starting to crashed
2016-09-05T23:36:51.867426+00:00 heroku[web.1]: Process exited with status 1