I’ve been doing something for real! A very
simple little polling site, that actually turned out
pretty ok (saved the UI but I have a friend brushing that up for me) and
might be useful.
It’s built with
KoaJs, of course,
database. Basically you can create a “question”, tag it with some meta
data and then send a link to a page where you can start receiving
answers. And there’s some very basic “export to excel”-reporting. Simple
stuff. I spent maybe 3-5 hours altogether on it, in the hospital bed
with my son in the bed next to me. He was pretty ok, so the
concentration was not on top on either tasks for me. Bad!
This Sunday I wanted to deploy the first version of it. To
Heroku. It went
pretty smooth but I wanted to share my story and some problems I ran
For the most part I was impressed over the smoothness and "it just
works"-factor throughout the deployment of my application. This article is a great starting point
applications and I suggest your read it before you start.
### Setting up Heroku
First you of course need to sign up
, so go
ahead and create an account there if you haven't already.
Locally you need something called the
. It's an easy install from their site and then you can read
this to get started. The tool belt is basically just a bunch of command
line commands that is really powerful.
The first things you probably use the tool belt for is probably:
login - to authenticate with the Heroku-site credentials
create \[appname\] - create an Heroku application in a
directory and on the Heroku site. And setup a nice link between them
that is the real power of Heroku.
keys:add - add your ssh-keys to let Heroku know that you are
you. Read this.
The last point was also my first gist. I'll soon come back to it. But I
need to explain one more command that you need to know about:
- git push
heroku \[branch\] - remember above where we created the
application. This also sets up a
for you. Aptly named heroku. This is awesome because it means that
we can move code to Heroku by a normal git push. If you're new to
git have a look here.
#### Error: git push heroku master -\> Permission denied (publickey)
I was happy. Everything had gone so great. I had installed and run the
Heroku tool belt command. They all worked like a charm. I even started
to think that I knew what I was doing. Then I pushed to Heroku for the
> git push
> heroku master
> Permission denied (publickey).
> fatal: Could not read from remote repository.
> Please make sure you have the correct access rights
This was strange. I had ssh-keys in place (if you have not,
read this article) since I was using GitHub that
used ssh-keys too. But apparently Heroku wanted them to be in special
files called "id_rsa" and "id_rsa.pub". I didn't have them. I had GitHub
and GitHub.pub. Thank you StackOverflow.
#### package.json and the engine-node
Oh yeah... almost forgot. I'm of course using
KoaJs for the app. I got tired of writing nested
functions... As you remember Koa needs a version of Node that is later
than the current version. You need to tell Heroku that you're planning
to use another version of node also, otherwise it will use the latest
Luckily this is super simple. In you
just define a node called
"engines" and give it the version of Node you're
using. Like this:
> "node": "0.11.12"
Thank you [Jonathan Channon](https://twitter.com/jchannon) for reminding
me to write this. Tripped me up at first.
Now I could push my code to Heroku. Great - but I needed a database as
well. Luckily Heroku is built around modules that you add to your
application. In Heroku-speak: addons that you provision. I choose
since I had heard that name before.
Installing the addon is super simple: heroku addons:add
The addon is then added to your application on the Heroku site and
configured as needed. But your are not using it in your application.
#### Getting it to work with your app
In order to use MongoHq in your application you need to get hold of the
URL to the MongoDb database. The MongoHq addon exposes this through
a environment variable which you can get hold of in Node by doing:
You can see the settings for you application
under https://dashboard.heroku.com/apps/\[your application
Now, this poses a bit of a problem since you want to use your local
MongoDb server when developing and the one in the cloud at MongoHq when
you are running live. There's myriads of ways to solve this but I have
dragged a little configuration utility around for a while. It's just a
single file that exports an object with the configuration variables I
need. Here is one incarnation of it:
The first lines sets up my database connection strings, and uses the
MONGOHQ_URL if it is present. I can then use my configuration object
when I create my database object (in this case using
Monk) like this:
> var config
> = require('../config')();
> var monk = require('monk');
> var wrap = require('co-monk');
> var db = monk(config.mongoUrl);
Ok, that worked just fine. Exceptionally actually. Because it just
worked. MongoHq rocks!
### Problems and logging
Now I hade everything installed. I pushed "the button" to Heroku and
Maw-maw-maw. I got a really strange error.
#### Error: Web process failed to bind to $PORT within 60 seconds of launch
When I opened my site (heroku open
form the command prompt by the way) it just gave me a bland: the site is
not working, contact your admin kind of message. Admin... hey that's me
in this case. I should probably read some logs or something.
Reading logs at the prompt is actually quite simple, albeit a bit
verbose in it's output: heroku logs
will flush the log before you eyes. If the log is really big you
can do "heroku logs -n
1500" (last 1500 events) or "heroku logs
-t" (100 last events).
But it's not very nice to read, nor searchable.
We need better. We need
Papertrail. Papertrail is a nice little addon that
helps you read your log. Install it (heroku addons:add
papertrail) and you get a dashboard for you app with a nice UI to
see, read and search your logs.
With that in place the Yak was shaved and I could get back to trying to
figure out why my site didn't show. There were two problems that
1. I was using
to start my application. It was not in my dependencies. Bad Marcus!
I added that and updated my "npm
start" command to point to the nodemon in my
"./node_modules/nodemon/bin/nodemon.js --harmony app.js
If nothing of that made any sense to you
read this first.
And then this.
2. I then ran into the "Web process failed to bind to $PORT within 60
seconds of launch" mentioned above. Let's talk more about that.
Heroku dynamically assigns your app a port, so you can't set the port to
a fixed number. Heroku adds the port to the env, so you can pull it from
there. Very much like the MONGOHQ_URL above. We need to use the
environment variable set dynamically by Heroku in the production case
and our local port in the local case. If you scroll back up you can see
that I do that in my config-object (line 18), where set the port of my
object to either the port from Heroku or a static one (port:
process.env.PORT \|\| 5000,)
There's always bumps in the road. These were mine. Overall I was still
very impressed with the smooth ride to live site in production that
Heroku and MongoHq treated me to.