DerekSeverson

Better local require() paths for Node.js

Problem

When the directory structure of your Node.js application (not library!) has some depth, you end up with a lot of annoying relative paths in your require calls like:

var Article = require('../../../models/article');

Those suck for maintenance and they're ugly.

Possible solutions

DerekSeverson

Whether you use 2 spaces or 4 spaces, there are a few simple things that can make your node.js code easier to read. We've been using them in all the hapi modules for over 4 years now to great results. This list is by no means complete but it highlights the most useful elements that will give you immediate value in reducing bugs.

Required modules

JavaScript makes it harder than most languages to know where variables are coming from. Variables assigned required modules are particularly important because they represent a singleton object shared with the entire application. There are also globals and module globals, along with function variables and arguments.

Traditionally, variables starting with an uppercase letter represent a class that must be instantiated using new. This was an important semantic in the early days of JavaScript but at this point, if you don't know Date requires new Date() you are probably very new. We have adopted Upper Camel Case variable names for all module global variables

DerekSeverson

Deploying a node app with Forever is great...until your server restarts unexpectedly. Then your app stops running and you have to re-deploy.

To get around this, we're going to run our node app as an Upstart service. Upstart services are great, because, once started, the system auto-restarts them if they fail, or if the server restarts.

###Step 1: Create a service for your node app

• ssh in as root ssh root@youripaddress
• Create a node-app.conf file in /etc/init
  IMPORTANT: whatever filename you pick is what you will use to start|stop|restart your service i.e. service node-app start

DerekSeverson

##Setup your server (this would ideally be done with automated provisioning)

• add a deploy user with password-less ssh see this gist
• install forever npm install -g forever

##Install flightplan

• npm install -g flightplan
• in your project folder npm install flightplan --save-dev
• create a flightplan.js file

DerekSeverson

(wherever it says url.com, use your server's domain or IP)

Login to new server as root, then add a deploy user

sudo useradd --create-home -s /bin/bash deploy
sudo adduser deploy sudo
sudo passwd deploy

And Update the new password

DerekSeverson

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

So you're curious in learning this new thing called (Functional) Reactive Programming (FRP).

Learning it is hard, even harder by the lack of good material. When I started, I tried looking for tutorials. I found only a handful of practical guides, but they just scratched the surface and never tackled the challenge of building the whole architecture around it. Library documentations often don't help when you're trying to understand some function. I mean, honestly, look at this:

Rx.Observable.prototype.flatMapLatest(selector, [thisArg])

Projects each element of an observable sequence into a new sequence of observable sequences by incorporating the element's index and then transforms an observable sequence of observable sequences into an observable sequence producing values only from the most recent observable sequence.