KICK ME

Keep It Complicated Keep Me Employed

KICK ME

• I am having trouble understanding this code.
• Let's take a look.
• Do you see this function? It calls these 13 other functions and has roughly 1000 lines of commented out code in it.
• Ah yes, that is the Job Security Design Pattern in action!

Hundred responsibilities principle

knows very much or does very much

Hundred responsibilities principle

Untestability

Profits of not having tests:

• not doing work no one pays for
• no problems with failing build on Jenkins
• increase need for manual testing
• more thrilling changes to the code
• make it harder to change the code without worrying that anything will get broken
• deprive us from having documentation for what the code is actually meant to do

Untestability

open/closed principle

Redefine the functionality

reinventing the wheel

re-implementing (limited) PHP functions

prefer implementing custom solutions over using open source library

overriding methods

Really big interfaces

big ⟶ complicated

complicated ⟶ advanced

advanced ⟶ smart

Really big interfaces

You should rely on others

class InvoicePdf extends FPDF
{
}

new Symfony\Component\Process\Process(/* ... */);

Bus factor

Bus factor

Bus factor

Bus factor

Bus factor

The number of team members who, if run over by a bus, would put the project in jeopardy.

The bigger the number is, more people are inreprecable in the procject.

Our goal is to descrease the bus factor.

Early Optimization

It is not difficult to know what will be the bottleneck.

Prefer efficiency over simplicity.

Try to cache everything you can.

Inheritance over composition

Magento\Backend\Block\System\Store\Edit\Form\Store

extends Magento\Backend\Block\System\Store\Edit\AbstractForm

extends Magento\Backend\Block\Widget\Form\Generic

extends Magento\Backend\Block\Widget\Form

extends Magento\Backend\Block\Widget

extends Magento\Backend\Block\Template

extends Magento\Framework\View\Element\Template

extends Magento\Framework\View\Element\AbstractBlock

extends Magento\Framework\DataObject

Inheritance over composition

WET

We Enjoy Typing

Weeks of programming can save you hours of planning

Weeks of programming can save you hours of planning

meetings = waste of time

Analysis Paralysis

Death By Planning

E-mail Is Dangerous

Naming

$bCorrect;
$iCount;
$sName;

class DatabaseUtil {}
class UserHelper {}
class PasswordManager {}
class AccountFunctions {}

Naming

Use short names and describe more in comment:

/*
 * This function returns random item
 * for matching name and category
 */
function get2($name, $category) { /* ...*/ }

Do abbreviate

$w; // this is username

Magic numbers and strings

class PasswordManager
{
    public function setPassword($password) {
        if (strlen($password) < 8) {
            throw new Exception('Password must me longer than 8 characters!');
        }
        /* ... */
    }
}

Magic numbers and strings

Anemic domain model

Contains little or no business logic (validations, calculations, business rules etc.).

• You can claim it's a domain model and brag to your developer friends and put it on your resume.
• It's easy to generate automagically from database tables.
• It maps to Data Transfer Objects surprisingly well.

Anemic domain model

Gypsy wagon

(Poltergeist)

(Big DoIt Controller Class)

When we anticipate the need for a more complex architecture.

Limited responsibilities and roles.

Effective life cycle is short.

Improbability factor

A problem exists in a system.

We are not going to fix the problem,

because chances of the problem ever surfacing are small.

Cargo cult programming

SODD

Stack Overflow Driven Development

We are ready now!

Clarification

One good programmer can easily create two new jobs a year.

Lack of optimization is the root of all evil.

Clarification

A module should be open for modification.

A module should be closed for extension.

Sources

• en.wikipedia.org/wiki/The_Dirty_Dozen
• mrrobot.fandom.com/wiki/E_Corp
• www.linkedin.com/pulse/job-security-design-pattern-jsdp-mike-veigel
• sahandsaba.com/nine-anti-patterns-every-programmer-should-be-aware-of-with-examples.html
• sourcemaking.com/antipatterns/software-project-management-antipatterns
• martinfowler.com/bliki/AnemicDomainModel.html
• stackoverflow.com/questions/258534/anemic-domain-model-pros-cons
• www.promptworks.com/blog/in-defense-of-cargo-cult-programming