Real World Lessons On The Anti-Patterns of Node.JS

REAL WORLD LESSONS ON THE ANTI-PATTERNS OF NODE.JS

@Ben_Hall

Ben@BenHall .me.uk

Blog.BenHall .me.uk

MY BATTLE SCARS OF NODE.JS

@Ben_Hall

Ben@BenHall .me.uk

Blog.BenHall .me.uk

MY LIFE, MY STORY, MY ANTI-PATTERNS

BY BEN HALL.

PUBLISHER TBC

$ whoami

Ocelot Uproar

Tea boy > Tester > Developer > Freelancer > Tea boy?

My main pain points & agenda

• Modules + NPM

• Project Structure

• Async

• Error Handling

Disclaimer

Examples are not a refl ection on the developer/team/company. Based on

problems I ’ve caused myself or struggled with. JavaScript is very

subjective…blah blah blah… If you’re doing it r ight then *amazing*! I ’m

not.

Love, Ben x

MODULES + NPM

AngularJs 1.2 => 1.3

1. "dependenc ies" : {

2. "angu lar" : "^1.2 .16”

3. }

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Angular 1.2 => 1.3

> angular.element(document)

[#document]

> angular.element(document)

TypeError: undefi ned is not a function

Lock Down Dependencies

Randomly breaking bui lds and deployments wil l occur

otherwise

$ npm shrinkwrap

Lock down dependencies to what’s running local ly

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Hard code versions in package.json

1. "dependencies": {

2. "angular": “1.2.23”

3. }

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$ npm outdated

$ npm install

Downloading the internet on each deployment can be

slow

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$ npm install --production

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“HELPERS” & PROJECT STRUCTURE

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Libs/<Context>/<Task>.js

Why not an NPM?

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ASYNC

Because J avaSc r ip t

Promises

Promises… Promises… Never break your promises.

Personal ly , never make promises.

http://domenic.me/2012/10/14/youre-missing-the-point-of-promises/

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Not part of the Node

Makes integration more diffi cult. Makes swapping

code in / out more painful.

Callbacks

So good it ’s got it ’s own website cal lbackhel l .com

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Loops + Async Callbacks��

Loops + Async Callbacks��

Generators are coming!

See Node >=0.11.2

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http://blog.alexmaccaw.com/how-yield-will-transform-node

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ERROR HANDLING

Wasn’t great from the start

Sti l l not great

Try {} Catch {}��

Try {} Catch {}��

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Returning String as Error��

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Zones are coming!

See Node >=0.11.2

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https://raw.githubusercontent.com/strongloop/zone/master/showcase/curl/curl-zone.js

Generators + Error Handling

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AND FINALLY

Node is *Amazing*

Let’s you get away with a lot without hurting too much

Modules + NPM

Pro jec t S t ructure

Async

Error Hand l ing

@Ben_Hall

Ben@BenHall .me.uk

Blog.BenHall .me.uk