Jose De Gouveia

Posted on Jun 1, 2020 • Edited on Sep 24, 2020

Write modern PHP without a framework

#php #api

Since the introduction of Composer package manager and the PHP standards, writing PHP became easier and more manageable, whereas in the past you were almost forced to use a framework to maintain your project in a professional matter, nowadays this is not necessary, and today I will show you how to glue together a small API project with basic routing, third party packages, and testing without a framework.

There are few reasons why you don't want to use a framework, you are creating a library, a small app/API, have more control and so forth, depending on your cases you might want to use a framework don't get me wrong.

Our goal is to create a simple Blog Api, each post will have an id, title, and body, you will able to list, create and view a post, we won't use any database, a simple JSON file that will act as DB should be enough, all request/responses will be in JSON format

As you see, there are some fields and features missing, like slug, summary, published date, author, tags, categories and so forth, or ability to delete/update, I decided to not implement those and I'll briefly explain some classes and code without getting into too much detail to make this article shorter, if you need extra explanation of any step please leave it in the comments and I will do my best to help you there.

All code is available in https://gitlab.com/dhgouveia/medium-blog-api

Prerequisites

PHP 7.0 or greater
Composer
Basic knowledge of PHP, classes, composer, MVC pattern

Ok, let's start!

Setting up Composer

The first thing we need to do is create our composer.json needed to add 3rd party packages and manage our project with the autoloading feature, this will make importing classes easier.

Create a folder and type composer init in your terminal and fill the information, it will create the composer.json file for us, then create our basic folder structure with some empty files called index.php, config.php and an empty folder called App

Let's add the first package by using the command line composer require monolog/monolog:1.25.1, it creates a vendor folder with the package we just added and a file called autoload.php, this file will contain all the path to the classes we add from 3rd parties and ours, monolog is a package to create logs files that will be used later on

Open index.php and fill it with:

<?php
require __DIR__ . '/vendor/autoload.php';

modify the composer.json by adding the autoload entry after the type entry

"type": "project",
"autoload": {
  "psr-4": {
    "App\\": "App/"
   }
}

then type composer dump-autoload to update the autoload entries, the autoload entry will register all our classes to be used anywhere in our app, psr-4 is a more flexible autoloading standard specification than psr-0, you don't need to regenerate the autoloader when you add classes or have folders that match your namespaces structure for example.

By now, the app is already setup to work with composer, you can run php index.php in the terminal, if no error is shown it means is working, this shouldn't output anything

Adding our first class

Let's make a Config helper to use across the project, we are going to have 2 files, config.php at the root of the project, with some settings for the app, here is where you put your API Key, Cache setting, etc, and you should have a different one base on your environment (test, stage, prod), and the other file will be App/Lib/Config.php to read those variables

Open config.php and fill it with:

<?php
return [
 'LOG_PATH' => __DIR__ . './logs',
];

create a new file inside App/Lib/ called it Config.php and paste this code

App/Lib/Config.php

This code reads the Array from config.php and check if the key exists in the array, if so return the value otherwise return the default value given

Let's check if working by editing the index.php adding these lines

<?php require __DIR__ . '/vendor/autoload.php';

// New lines
use App\Lib\Config;
$LOG_PATH = Config::get('LOG_PATH', '');

echo "[LOG_PATH]: $LOG_PATH";

now run php index.php and should output the path of the logs specified on config.php

It seems not much but at this point, you should be getting an idea how the rest of the code will work, we'll add some classes into App folder and thanks to the autoloading will be accessible anywhere in the app.

So if you manage to follow along until here, congrats! grab some coffee and let's continue.

Adding Logging

Earlier we added the monolog package to our dependencies, this package contains a series of classes and helper to manage logs. Logging is an essential part of any app since it will be the first thing you'll check when anything goes wrong and packages like monolog make this job easier and even the possibility to send those via email, slack, telegram, you name it!, for this app, I want to create three simple log files errors.log, requests.log and app.log

errors and requests logs will be active all the time and app logs will be used on demand for us to display desire information, errors.log will contain any error that happens in the app, requests.log will log any HTTP request made to the app

create App/Lib/Logger.php and paste the code below, this will be a wrapper that will manage our different logs

App/Lib/Logger.php

now we have two main functions Logger::enableSystemLogs() this will enable our error/request logs, and then we have Logger::getInstance() that by default will be our App log, let's try it, modify our index.php once again with these new lines

<?php require __DIR__ . '/vendor/autoload.php';

use App\Lib\Config;
$LOG_PATH = Config::get('LOG_PATH', '');
echo "[LOG_PATH]: $LOG_PATH";

//New Lines
use App\Lib\Logger;

Logger::enableSystemLogs();
$logger = Logger::getInstance();
$logger->info('Hello World');

type php -S localhost:8000 it'll run a built-in web server that is present in PHP since 5.4, navigate to http://localhost:8000, you should see the "LOG_PATH", but if you check your logs folder you will see two files, showing the requested content and another one with "Hello World" text, take a time to tweak the request if you need to show specific info or remove it, this was meant to show different types of logging

finally lets clean a little bit our index.php and create a new file called App/Lib/App.php , let's use this as a bootstrap to our app

App/Lib/App.php

and update the index.php

<?php require __DIR__ . '/vendor/autoload.php';
use App\Lib\App;

App::run();

looks much nicer right?

Adding Routing

In any modern app, routing takes a huge part of it, this will call a specific code based on the path in the URL we choose, for example / could show the homepage, /post/1 could show the post information with id 1, for this we will implement three classes Router.php , Request.php and Response.php

Our Router.php will be very basic, it will verify the request method and match the path we are giving using regex, if match, it will execute a callback function given by us with two parameters Request and Response, Request.php will have some functions to get the data that was sent in the request, for example, the Post data such as title, body to create it, and Response.php will have some functions to output as JSON with specific HTTP status.

create App/Lib/Router.php, App/Lib/Request.php, App/Lib/Response.php

App/Lib/Router.php

App/Lib/Request.php

App/Lib/Response.php

update your index.php with the code below,

index.php

type php -S localhost:8000 to test it and navigate to http://localhost:8000/ and you should see 'Hello World' and http://localhost:8000/post/1, you should see a JSON response with status 'ok' and the id you gave inside 'Post'

{"status": "ok", "post": { "id" : 1} }

if you are using Apache you might need to add this .htaccess file to the root of your project

RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME} !-f
RewriteRule ^(.+)$ index.php [QSA,L]

in the case of Nginx

location / {
  try_files $uri $uri/ /index.php$is_args$args;
}

Great! our app now have routing! is time to take a break again, go and grab some lunch! , You want to continue? ok as a bonus let's add a really simple Controller, this might be useful in the future if you want to use a template engine like Twig

create App/Controller/Home.php

App/Controller/Home.php

and modify the Router::get('/',..) in the index.php with

use App\Controller\Home;

Router::get('/', function () {
   (new Home())->indexAction();
});

Implementing our Blog API

Finally!, we are almost over!, in these steps, we are finally implementing our Blog API, thanks to our Router, the next steps will be easy,

We will have three endpoints

GET /post, list all the available post
POST /post, Create a new Post
GET /post/{id}, show and specific post

First, we need our Posts model to handle these operations and then be called from our router

create App/Model/Posts.php

App/Model/Posts.php

create a db.json file in the root of the project and paste this so we can have a content already to test

[
   {
     "id": 1,
     "title": "My Post 1",
     "body": "My First Content"
   }
]

modify our config.php to add the DB_PATH

<?php
return [
 'LOG_PATH' => __DIR__ . './logs',
 'DB_PATH' => __DIR__ . '/db.json'
];

with this we already have our "DB" setup, now we need to use it with our router, let's modify our index.php to add the routes and DB call respectively

index.php

in this step, we added Posts::load() to load our "DB" from the db.json file and created three routes GET /post to list, POST /post to create and GET /post/([0–9]*) to get a specific post , you could move the Posts::load() inside our App::run method to make it cleaner.

Great! let's test it!, you could use postman, curl, to simulate the POST request

List all posts curl -X GET http://localhost:8000/post should output:

[{"id":1,"title":"My Post 1","body":"My First Content"}]

List one post curl -X GET http://localhost:8000/post/1 should output:

{"id":1,"title":"My Post 1","body":"My First Content"}

Create a post

curl -X POST \
 http://localhost:8000/post \
 -H 'Content-Type: application/json' \
 -d '{"title": "Hello World", "body": "My Content"}'

Finally! is finished! we have our Blog Api working! if you manage to follow along until here and you didn't get bored, Congrats once again!, but before we wrap up, let's add some testing and I promise we'll finish

Adding Testing

Ok, we got this far, so let's implement some testing, for this step, I will test only our Router.php with simple cases and the code styling based on psr-2 coding style standard, but you should take the time to test as much you can in your app, my intention is just to show you how to add this into our app and CI

we need to add some package into our project, type

composer require --dev squizlabs/php_codesniffer
composer require --dev peridot-php/peridot
composer require --dev peridot-php/leo
composer require --dev eloquent/phony-peridot

run in the terminal ./vendor/bin/phpcs - standard=psr2 App/ to check if any code syntax is wrong, this will be part of our test script, but try to run it now, in case you have only white-spaces errors, you could use ./vendor/bin/phpcbf - standard=psr2 App/ to fix it automatically.

for unit testing, we are going to use my personal choice peridot but you could use any you feel comfortable, besides peridot, we have two plugins leo provides expect functionality and phony-peridot provides stubs functionality that is very handy to check if a function was called

create Test/Router.spec.php

Test/Router.spec.php

modify the composer.json and add this section below

"scripts": {
   "test": [
     "./vendor/bin/phpcs --standard=psr2 App/",
     "./vendor/bin/peridot Test/"
   ]
}

now to run the test, you could just type ./vendor/bin/peridot Test/ or composer run-script test or even shorter with composer test all of them would do the same if everything went right you see this.

Conclusions

This was a very simple project and a lot of things was left out to keep the article shorter as possible, but you could use it as a base and extended it by adding a better router, an ORM, template engine and so forth, take time and check https://packagist.org/explore/popular or https://thephpleague.com/#packages

All code is available in https://gitlab.com/dhgouveia/medium-blog-api

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