PHP Framework for creating mockable code

Intro

This class provides abstractions from basic infrastructure things wich can make you unit-testing harder. For example:

• console output
• file system operations
• GD library
• redirections
• sessions
• system methods

If you will write your code using this framework then your unit-tests will be much easier to write and support. And as aconsequence - your code will be more stable.

Basic concepts

Each abstraction can be setup to use either native function calls (such as file_get_contents) or mockups.

Mockuped calls can be used in your unit-tests. And native calls will be executed in production.

Let's see some real code examples:

// here we setup mock calls
\Mezon\Conf\Conf::setConfigStringValue('fs/layer', 'mock');

// here we setup that mock will return true if the we check that this directory exists
\Mezon\Fs\Layer::$createdDirectories[] = [
    'path' => 'path-to-existing-directory'
];

// here we will get true
var_dump(\Mezon\Fs\Layer::directoryExists('path-to-existing-directory'));

// and here we will get false
var_dump(\Mezon\Fs\Layer::directoryExists('path-to-unexisting-directory'));

In both calls Mezon\Fs\Layer::directoryExists no real call of method file_exists was performed.

No let's see what abstractions we have

Console layer

Class Mezon\Console\Layer provides abstractions for working winth console

// here we setup mock calls
Conf::setConfigStringValue('console/layer', 'mock');

// setup values wich will be returned by the method Mezon\Console\Layer::readline()
\Mezon\Console\Layer::$readlines[] = 'line 1';
\Mezon\Console\Layer::$readlines[] = 'line 2';

// read lines
// note that native php method `readline` will noe be called
// just returning value of the Mezon\Console\Layer::$readlines array
echo \Mezon\Console\Layer::readline(); // ouputs 'line 1'
echo \Mezon\Console\Layer::readline(); // ouputs 'line 2'

// here we setup native php methods calls
Conf::setConfigStringValue('console/layer', 'real');
echo \Mezon\Console\Layer::readline(); // outputs string wich you will input in the console
// because in this line real method `readline` will be called

File system layer

This package also have abstractions for file systems routine:

// here we setup mock calls
Conf::setConfigStringValue('fs/layer', 'mock');

// writing file
\Mezon\Fs\Layer::filePutContents('file-path', 'data', FILE_APPEND);
// ^^^ but in this call all file content will be stored into memory, not on disk
// on production this call works like file_put_contents

// creating directory
\Mezon\Fs\Layer::createDirectory('new-dir');
// ^^^ real directory also is not created

// checking if the directory exists
echo \Mezon\Fs\Layer::directoryExists('new-dir'); // we shall see 'true', because we have called \Mezon\Fs\Layer::createDirectory('new-dir');
echo \Mezon\Fs\Layer::directoryExists('unexisting-dir'); // we shall see 'false'

// checking if the file exists
echo \Mezon\Fs\Layer::fileExists('file-path'); // we shall see 'true', because we have called \Mezon\Fs\Layer::filePutContents('file-path', 'data', FILE_APPEND)
echo \Mezon\Fs\Layer::fileExists('unexisting-file-path'); // we shall see 'false'

// getting file contents
echo \Mezon\Fs\Layer::fileGutContents('file-path'); // we shall see 'data', because we have already called \Mezon\Fs\Layer::filePutContents('file-path', 'data', FILE_APPEND)
echo \Mezon\Fs\Layer::fileGutContents('unexisting-file-path'); // we shall see 'false'

In-memory file system

Almost all methods from \Mezon\Fs\Layer in mock mode use \Mezon\Fs\InMemory.

// writing data in memory file system
\Mezon\Fs\InMemory::filePutContents('file-path', 'data');

// reading data from inmemory file system
echo \Mezon\Fs\InMemory::fileGetContents('file-path');

// checking that file esists
echo \Mezon\Fs\InMemory::fileExists('file-path'); // outputs 'true'
echo \Mezon\Fs\InMemory::fileExists('unexisting-file'); // outputs 'false'

// preload file in FS
// this method reads real file from your FS and uploads it into inmemory FS
\Mezon\Fs\InMemory::preloadFile('real-file-path');

GD mocks

We also have mocks for some GD functions. Basically for those ones wich work with file system.

Conf::setConfigStringValue('gd/layer', 'mock');
// here we are trying to get file with this path from \Mezon\FS\InMemory
var_dump(\Mezon\GD\Layer::getImageSize('path-to-image'));

// reading image from file
$resource = \Mezon\GD\Layer::imageCreateFromBmp('path-to-image-file');
$resource = \Mezon\GD\Layer::imageCreateFromGif('path-to-image-file');
$resource = \Mezon\GD\Layer::imageCreateFromJpeg('path-to-image-file');
$resource = \Mezon\GD\Layer::imageCreateFromPng('path-to-image-file');
$resource = \Mezon\GD\Layer::imageCreateFromWebp('path-to-image-file');

// store images into file. In mock mode all data is stored into in-memory FS - \Mezon\FS\InMemory
\Mezon\GD\Layer::imageBmp($resource, 'path-to-file');
\Mezon\GD\Layer::imageGif($resource, 'path-to-file');
\Mezon\GD\Layer::imageJpeg($resource, 'path-to-file');
\Mezon\GD\Layer::imagePng($resource, 'path-to-file');
\Mezon\GD\Layer::imageWebp($resource, 'path-to-file');

Redirection mocks

You can mock redirects:

Conf::setConfigStringValue('redirect/layer', 'mock');

// in real mode this call method header('Location: ...') will be called
// in mock mode no redirection will be performed and redirect URL will be stored
// in the \Mezon\Redirect\Layer::$lastRedirectionUrl
// and \Mezon\Redirect\Layer::$redirectWasPerformed will be set to 'true'
\Mezon\Redirect\Layer::redirectTo('./url');

Session mocks

You can also mock session methods:

Conf::setConfigStringValue('session/layer', 'mock');

// method returns 'session-name' if it is used as mock mode
// and return result of session_name() if it is used in real model
\Mezon\Session\Layer::sessionName();

// setting cookie 
\Mezon\Session\Layer::setCookie(
        string $name,
        string $value = "",
        int $expires = 0,
        string $path = "",
        string $domain = "",
        bool $secure = false,
        bool $httponly = false);

// getting session id or setting it
\Mezon\Session\Layer::sessionId(string $id = ''): string;

// saving session data and closing session
\Mezon\Session\Layer::sessionWriteClose();

System methods mocks

You can also mock some system methods calls. Like die for example:

Conf::setConfigStringValue('system/layer', 'mock');

// in mock mode field $dieWasCalled will be set to 'true'
// in real mode built-in PHP method 'die' will be called
\Mezon\System\Layer::die();

What's next?

More articles can be found in my Twitter

What is mezon/infrastructure-layer?

mezon/infrastructure-layer now is:

• framework for creating easy mockable code with 100% code coverage
• mezon/infrastructure-layer is a part of the Mezon Project
• repo on github.com: https://github.com/alexdodonov/mezon-infrastructure-layer

It will be great if you will contribute something to this project. Documentation, sharing the project in your social media, bug fixing, refactoring, or even submitting issue with question or feature request. Thanks anyway )