throwing laravel into your legacy app™

Throwing Laravel into your Legacy™ Application

Joe Ferguson

Who Am I?

Joe Ferguson

PHP Developer

PHP Architect @ Ministry Brands

Twitter: @JoePFerguson

Organizer of @MemphisPHP

@NomadPHP Lightning Talks

Drone Racing Pilot

For Further Reading

leanpub.com/mlaphplaravelupandrunning.com

First: A Warning

Legacy Applications

“There are no solutions, only trade offs”

- Joe Ferguson

- Paul M. Jones

- Thomas Sowell

What is a "Legacy" application

Legacy is often used for an older production application that was written before, or without regard for modern technologies or practices.

If you ask Wikipedia…

"... no-longer supported …"

"... maintained by an administrator that did not develop the code …"

"... supporting older file formats ..."

https://en.wikipedia.org/wiki/Legacy_code

Modern Interpretation

"... source code inherited from someone else …"

"... source code inherited from an older version of the software ..."

Some people say…

"Any code in production is not legacy”

"Any code written X years ago is legacy"

Legacy is all these things

As we talk about Legacy code here, we're really talking about all of these definitions

This process is not Legacy Specific…

Initial Project Overview

Is there a framework?

Is there a coding standard?

Is there any autoloading?

How are dependencies behind handled?

Is there an ORM or how is the database being utilized?

Is there a development environment?

Is there a framework?

Is there a coding standard?

There is a PSR for that…

How are dependencies behind handled?

Is there an ORM or how is the database being utilized?

Tools to help

PHP Coding Standards Fixerhttp://cs.sensiolabs.org/

PHP Coding Standards Fixerphp-cs-fixer fix app --dry-run

PHP Mess Detectorhttps://phpmd.org

PHP Mess Detectorhttps://phpmd.org

$ phpmd app html cleancode --reportfile report.html

Warning about Automating Code Changes

Triage

Address any critical things found in Contemplation phase

PHP version issues

Fixing critical vulnerabilities

“We should just rewrite the app”

"This would be so much easier in framework _____________”

Why not rewrite?

Progress halts entirely

Business logic is rarely reused

Most of the time is getting back to current functionality

Why you should refactor

Progress continues

Business logic reused

Modernizing functionality instead of recreating

Make Decisions

Build Proof of Concept(s)

Ensure stakeholder buy in

Avoid the allure of green fields**

** in some cases a rewrite is warranted

Refactoring Approach

Existing Tests

This is great!

Review the tests to get an idea of coverage

Passing tests become your control for any upcoming changes

Confidence++

No Existing Tests

Not the end of the world!

Inspect the code base, was it written to be easily testable?

Could you easily mock dependencies?

Untestable Code

Not all code is testable

If you can’t easily unit test the code base, consider alternatives

Functional testing and Acceptance testing are valid options

Acceptance Testing

NOT a replacement for Unit Testing

Test large parts of your application at a time

Can be harder to pinpoint error location

Gives large code coverage in short amount of time

Digging into the Code

Code Consolidation


Code Consolidation

Replace globals with DI


Code Consolidation

Replace globals with Dependency Injection

Write tests


Code Consolidation


Write tests

Extract SQL (to ORM or other)


Code Consolidation


Write tests


Extract Business Logic (To domain logic)


Code Consolidation


Write tests



Extract Presentation Logic to Views (Twig, Blade, etc)


Code Consolidation


Write tests




Extract Action Logic (To Controllers)


Code Consolidation


Write tests




Extract Action Logic (To Controllers)

Write (more) tests

Continuous Integration

Where does Laravel fit in?

You can easily** use Laravel components in your Legacy App

** Relatively speaking, and not all components

Laravel Component Goals

Implement Configuration

Implement Logging

Implement Routing

Implement Database

Implement Container

Configuration

https://github.com/mattstauffer/Torch/tree/master/components/config

What about secrets?

composer require vlucas/phpdotenv

composer require vlucas/phpdotenv

.env

config/app.php

Access Config the same way

Now our config is outside VCS

Do NOT version control your .env file!

Logging

https://github.com/mattstauffer/Torch/tree/master/components/log

Logging

You’ll likely want to configure your logger into a base class

that is extended

Routing

https://github.com/mattstauffer/Torch/tree/master/components/routing

Routing

Database

https://github.com/mattstauffer/Torch/tree/master/components/database

Container

https://github.com/mattstauffer/Torch/tree/master/components/container

Containers are very powerful. Make sure you’re not adding

spaghetti code just to shoehorn into your App

Recap

Follow a refactoring process

Leverage Laravel components as you refactor

Make sure you write tests along the way!

Joe FergusonTwitter: @JoePFergusonEmail: [email protected]: joepferguson

Contact Info:

https://joind.in/talk/d306e

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