How to fetch data from yaml file in php

1. Create your YAML file (e.g. data.yaml)

database:
  host: localhost
  port: 3306
  credentials:
    username: root
    password: secret

settings:
  debug: true
  cache: false
  rates: [1.0, 2.0, 3.0]

servers:
  - name: server1
    ip: 192.168.1.1
  - name: server2
    ip: 192.168.1.2

2. Create Class

class SimpleYamlParser {

3. Create the object of class and pass yaml file name

$parser = new SimpleYamlParser();
$data = $parser->parseFile('data.yaml');

4. Access your data with object

if ($data !== false) {
    // Access your data
    echo $data['database']['host'];          // outputs: localhost
    echo $data['settings']['debug'];         // outputs: 1 (true)
    echo $data['servers'][0]['name'];        // outputs: server1
    print_r($data['settings']['rates']);     // outputs array of numbers
}

Complete code:

<?php

class SimpleYamlParser {
    private $indentSpaces = 2;
    
    public function parseFile($filePath) {
        try {
            // Check if file exists
            if (!file_exists($filePath)) {
                throw new Exception('File not found: ' . $filePath);
            }

            // Read file content
            $content = file_get_contents($filePath);
            if ($content === false) {
                throw new Exception('Unable to read file: ' . $filePath);
            }

            return $this->parse($content);
        } catch (Exception $e) {
            error_log('YAML Parser Error: ' . $e->getMessage());
            return false;
        }
    }

    public function parse($yamlString) {
        // Remove comments and empty lines
        $lines = array_filter(explode("\n", $yamlString), function($line) {
            $trimmedLine = trim($line);
            return $trimmedLine !== '' && !str_starts_with($trimmedLine, '#');
        });

        $result = [];
        $currentPath = [];
        $previousIndent = -1;

        foreach ($lines as $line) {
            // Count leading spaces for indentation level
            $indent = strlen($line) - strlen(ltrim($line));
            $indent = floor($indent / $this->indentSpaces);
            
            // Remove leading/trailing whitespace
            $line = trim($line);

            // Skip empty lines and comments
            if (empty($line) || $line[0] === '#') {
                continue;
            }

            // Parse key and value
            if (strpos($line, ':') !== false) {
                list($key, $value) = array_pad(explode(':', $line, 2), 2, '');
                $key = trim($key);
                $value = trim($value);

                // Adjust current path based on indentation
                while (count($currentPath) > $indent) {
                    array_pop($currentPath);
                }

                if (empty($value)) {
                    // This is a new nested level
                    $currentPath[$indent] = $key;
                } else {
                    // This is a key-value pair
                    // Handle different value types
                    $value = $this->parseValue($value);
                    
                    // Build the complete path and set the value
                    $target = &$result;
                    for ($i = 0; $i < $indent; $i++) {
                        if (isset($currentPath[$i])) {
                            if (!isset($target[$currentPath[$i]])) {
                                $target[$currentPath[$i]] = [];
                            }
                            $target = &$target[$currentPath[$i]];
                        }
                    }
                    $target[$key] = $value;
                }
            } else if (str_starts_with($line, '-')) {
                // Handle array items
                $value = trim(substr($line, 1));
                $value = $this->parseValue($value);
                
                $target = &$result;
                for ($i = 0; $i < $indent; $i++) {
                    if (isset($currentPath[$i])) {
                        if (!isset($target[$currentPath[$i]])) {
                            $target[$currentPath[$i]] = [];
                        }
                        $target = &$target[$currentPath[$i]];
                    }
                }
                
                $lastKey = end($currentPath);
                if ($lastKey) {
                    if (!is_array($target[$lastKey])) {
                        $target[$lastKey] = [];
                    }
                    $target[$lastKey][] = $value;
                }
            }

            $previousIndent = $indent;
        }

        return $result;
    }

    private function parseValue($value) {
        $value = trim($value);
        
        // Handle null
        if ($value === '~' || strtolower($value) === 'null') {
            return null;
        }
        
        // Handle booleans
        if (strtolower($value) === 'true') {
            return true;
        }
        if (strtolower($value) === 'false') {
            return false;
        }
        
        // Handle numbers
        if (is_numeric($value)) {
            return strpos($value, '.') !== false ? (float)$value : (int)$value;
        }
        
        // Handle quoted strings
        if (preg_match('/^([\'"])(.*)\1$/', $value, $matches)) {
            return $matches[2];
        }
        
        return $value;
    }
}

// Example usage:

$parser = new SimpleYamlParser();
$data = $parser->parseFile('data.yaml');

if ($data !== false) {
    // Access your data
    echo $data['database']['host'];          // outputs: localhost
    echo $data['settings']['debug'];         // outputs: 1 (true)
    echo $data['servers'][0]['name'];        // outputs: server1
    print_r($data['settings']['rates']);     // outputs array of numbers
}

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