linitng setup added for PHP

.editorconfig

@@ -0,0 +1,49 @@
+# EditorConfig helps maintain consistent coding styles
+# https://editorconfig.org
+
+root = true
+
+# All files
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+trim_trailing_whitespace = true
+
+# PHP files
+[*.php]
+indent_style = space
+indent_size = 4
+
+# JavaScript files
+[*.js]
+indent_style = space
+indent_size = 2
+
+# CSS files
+[*.css]
+indent_style = space
+indent_size = 2
+
+# JSON files
+[*.json]
+indent_style = space
+indent_size = 2
+
+# YAML files
+[*.{yml,yaml}]
+indent_style = space
+indent_size = 2
+
+# Markdown files
+[*.md]
+trim_trailing_whitespace = false
+
+# Makefile
+[Makefile]
+indent_style = tab
+
+# SQL files
+[*.sql]
+indent_style = space
+indent_size = 4

.gitignore

@@ -7,3 +7,7 @@ docs/site/
 *.DS_store
 openml_OS/vendor/
 openapi/vendor/
+
+# PHP linting cache files
+.php-cs-fixer.cache
+.phpcs-cache

.php-cs-fixer.php

@@ -0,0 +1,50 @@
+<?php
+
+use PhpCsFixer\Config;
+use PhpCsFixer\Finder;
+
+$finder = Finder::create()
+    ->in([
+        __DIR__ . '/openml_OS/controllers',
+        __DIR__ . '/openml_OS/models',
+        __DIR__ . '/openml_OS/helpers',
+        __DIR__ . '/openml_OS/libraries',
+        __DIR__ . '/openml_OS/core',
+    ])
+    ->exclude([
+        'vendor',
+        'third_party',
+        'cache',
+        'logs',
+    ])
+    ->name('*.php')
+    ->notName('*.blade.php')
+    ->ignoreDotFiles(true)
+    ->ignoreVCS(true);
+
+return (new Config())
+    ->setRules([
+        '@PSR12' => true,
+        'array_syntax' => ['syntax' => 'short'],
+        'ordered_imports' => ['sort_algorithm' => 'alpha'],
+        'no_unused_imports' => true,
+        'not_operator_with_successor_space' => false,
+        'trailing_comma_in_multiline' => ['elements' => ['arrays']],
+        'phpdoc_scalar' => true,
+        'unary_operator_spaces' => true,
+        'binary_operator_spaces' => true,
+        'blank_line_before_statement' => [
+            'statements' => ['break', 'continue', 'declare', 'return', 'throw', 'try'],
+        ],
+        'phpdoc_single_line_var_spacing' => true,
+        'phpdoc_var_without_name' => true,
+        'single_trait_insert_per_statement' => true,
+        'space_after_semicolon' => true,
+        'no_whitespace_in_blank_line' => true,
+        'concat_space' => ['spacing' => 'one'],
+    ])
+    ->setFinder($finder)
+    ->setLineEnding("\n")
+    ->setIndent("    ") // 4 spaces
+    ->setUsingCache(true)
+    ->setCacheFile(__DIR__ . '/.php-cs-fixer.cache');

.phpcs.xml

@@ -0,0 +1,41 @@
+<?xml version="1.0"?>
+<ruleset name="OpenML Coding Standards">
+    <description>PHP CodeSniffer configuration for OpenML</description>
+
+    <!-- Show progress and use colors -->
+    <arg value="p"/>
+    <arg name="colors"/>
+
+    <!-- Use PSR-12 as base standard -->
+    <rule ref="PSR12"/>
+
+    <!-- Check these directories -->
+    <file>openml_OS/controllers</file>
+    <file>openml_OS/models</file>
+    <file>openml_OS/helpers</file>
+    <file>openml_OS/libraries</file>
+    <file>openml_OS/core</file>
+
+    <!-- Exclude vendor and third-party directories -->
+    <exclude-pattern>*/vendor/*</exclude-pattern>
+    <exclude-pattern>*/third_party/*</exclude-pattern>
+    <exclude-pattern>*/cache/*</exclude-pattern>
+    <exclude-pattern>*/logs/*</exclude-pattern>
+    <exclude-pattern>*/system/*</exclude-pattern>
+
+    <!-- Relaxed rules for legacy CodeIgniter code -->
+    <rule ref="PSR1.Classes.ClassDeclaration.MissingNamespace">
+        <severity>0</severity>
+    </rule>
+
+    <!-- Allow CodeIgniter naming conventions -->
+    <rule ref="Squiz.Classes.ValidClassName.NotCamelCaps">
+        <severity>0</severity>
+    </rule>
+
+    <!-- Set encoding -->
+    <config name="encoding" value="utf-8"/>
+
+    <!-- Set tab width -->
+    <arg name="tab-width" value="4"/>
+</ruleset>

openml_OS/composer.json

@@ -18,6 +18,14 @@
 		"paragonie/random_compat": "Provides better randomness in PHP 5.x"
 	},
 	"require-dev": {
-		"mikey179/vfsstream": "1.6.*"
+		"mikey179/vfsstream": "1.6.*",
+		"squizlabs/php_codesniffer": "^3.7",
+		"friendsofphp/php-cs-fixer": "^3.40"
+	},
+	"scripts": {
+		"lint": "phpcs --standard=.phpcs.xml",
+		"lint:fix": "phpcbf --standard=.phpcs.xml",
+		"cs:check": "php-cs-fixer fix --dry-run --diff",
+		"cs:fix": "php-cs-fixer fix"
 	}
 }