[JsonConfig] A simple PHP class to manage your app's settings. #settings #microlibrary

JsonConfig.php

<?php 

namespace SBRL\Utilities;

use \stdClass;

/**
 * Handles the loading and saving of settings from a file.
 * Supports loading default settings from a separate file.
 * @author			Starbeamrainbowlabs
 * @version			v0.2
 * @lastModified	22nd March 2017
 * @license			https://www.mozilla.org/en-US/MPL/2.0/	Mozilla Public License 2.0
 * Changelog:
 	 * v0.3 - 5th March 2018
    	* Fix variable reference errors
	 * v0.2 - 22nd March 2017
		 * Add license
		 * Filled in some missing comments
	 * v0.1: 28th February 2017
		 * Initial release
 */
class JsonConfig
{
	private $defaultSettings;
	
	private $settingsFilePath = "";
	/**
	 * The custom settings object.
	 * @var stdClass
	 */
	private $customSettings;
	
	/**
	 * Creates a new JsonConfig
	 * @param string $settingsFilePath			The path to the customised settings file.
	 * @param string $defaultSettingsFilePath	The path to the default settings file.
	 */
	public function __construct($settingsFilePath, $defaultSettingsFilePath) {
		$this->defaultSettings = json_decode(file_get_contents($defaultSettingsFilePath));
      	$this->settingsFilePath = $settingsFilePath;
      	$this->defaultSettingsFilePath = $defaultSettingsFilePath;
		
		$this->customSettings = new stdClass();
		if(file_exists($this->settingsFilePath)) {
			$this->customSettings = json_decode(file_get_contents($this->settingsFilePath));
		}
	}
	/**
	 * Gets the value identified by the specified property, in dotted notation (e.g. `Network.Firewalling.Ports.Http`)
	 * @param	string	$key	The property, in dotted notation, to return.
	 * @return	mixed			The value odentified by the given dotted property notation.
	 */
	public function get($key) {
		if(static::hasPropertyByPath($this->customSettings, $key)) {
			return static::getPropertyByPath($this->customSettings, $key);
		}
		return static::getPropertyByPath($this->defaultSettings, $key);
	}
	/**
	 * Fetches the default value for the specified property, specified in dotted notation.
	 * @param  string	$key	The key to fetch.
	 * @return mixed	The default value of the property identified by the given dotted notation.
	 */
	public function getDefault($key) {
		return static::getPropertyByPath($this->defaultSettings, $key);
	}
	/**
	 * Determines whether the given property has been customised or explicitly specified in the customised settings file.
	 * @param	string	$key	The property, in dotted notation, to check.
	 * @return	boolean			Whether the specified properties file has been explicitly specified in the custom settings file.
	 */
	public function hasChanged($key) {
		return static::hasPropertyByPath($this->customSettings, $key);
	}
	/**
	 * Sets the property identified by the specified dotted path.
	 * Does not re-save the properties back to disk!
	 * @param	string	$key	The dotted path to update.
	 * @param	mixed	$value	The value to set the property to.
	 * @return	self			This ConfigFile instance, to aid method chaining.
	 */
	public function set($key, $value) {
		static::setPropertyByPath($this->customSettings, $key, $value);
	}
	
	/**
	 * Saves the customised settings back to the disk.
	 * @return boolean Whether the save was successful or not.
	 */
	public function save() {
		return file_put_contents($this->settingsFilePath, json_encode($this->customSettings, JSON_PRETTY_PRINT));
	}
	
	/**
	 * Works out whether a given dotted path to a property exists on a given object.
	 * @param	stdClass  	$obj	The object to search.
	 * @param	string		$path	The dotted path to search with. e.g. `Network.Firewall.OpenPorts`
	 * @return	boolean		Whether the given property is present in the given object.
	 */
	public static function hasPropertyByPath($obj, $path) {
		$pathParts = explode(".", $path);
		$subObj = $obj;
		foreach($pathParts as $part) {
			if(!isset($subObj->$part))
				return false;
			$subObj = $subObj->$part;
		}
		return true;
	}
	/**
	 * Returns the property identified by the given dotted path.
	 * If you're not sure whether a property exists or not, use static::hasPropertyByPath() first to check.
	 * @param	stdClass	$obj	The object to fetch from.
	 * @param	string		$path	The path to extract from the given object.
	 * @return	mixed				The property identified by the given object.
	 */
	public static function getPropertyByPath($obj, $path) {
		$pathParts = explode(".", $path);
		$subObj = $obj;
		foreach($pathParts as $part) {
			$subObj = $subObj->$part;
		}
		return $subObj;
	}
	/**
	 * Returns the property identified by the given dotted path.
	 * If you're not sure whether a property exists or not, use static::hasPropertyByPath() first to check.
	 * @param	stdClass	$obj	The object to set the property on.
	 * @param	string		$path	The path to set on the given object.
	 * @param	mixed		$value	The value to  set the given property to.
	 */
	public static function setPropertyByPath($obj, $path, $value) {
		$pathParts = explode(".", $path);
		$pathPartsCount = count($pathParts);
		
		$subObj = $obj;
		for($i = 0; $i < $pathPartsCount; $i++) {
			// Set the property on the last iteration
			if($i + 1 == $pathPartsCount) {
				$subObj->$part = $value;
				break;
			}
			// Create sub-objects if they dobn't exist already
			if(!isset($subObj->$part)) {
				$subObj->$part = new stdClass();
			}
			$subObj = $subObj->$part;
		}
	}
}