Refactor using MVC (model and controller) + clean code with comments

vesseltracker/api/Utils.php

@@ -0,0 +1,185 @@
+<?php 
+namespace api;
+
+class Utils {
+
+    /**
+     * Check if request is allowed. 
+     * Request are limeted to 10 succesfully answered per hour per user (by ip address)
+     *
+     * @param string $ip
+     * @return boolean
+     */
+    public static function requestIPisAllowed(string $ip){
+        $file = fopen(getcwd().'/logs/access.log', 'r');
+        $ln = 0; 
+        $linestring = array();
+        $output = array();
+        for($x_pos = 0; fseek($file, $x_pos, SEEK_END) !== -1 && count($output) < 10; $x_pos--) {
+            $char = fgetc($file);
+            if ($char === "\n") {
+                if (strpos($linestring[$ln], '/api/v1/track') !== false && // line contains '/api/v1/tracks'
+                    strpos($linestring[$ln], 'HTTP/1.1" 20') !== false &&  // line contains 'HTTP/1.1" 20x'
+                    strpos($linestring[$ln], $ip) !== false ){              // line contains request ip address
+                    // add timestamp to output array
+                    array_push($output, explode( ']', explode( '[', $linestring[$ln] )[1])[0]);
+                }
+                // go to next line
+                $ln++;
+                continue;
+            }
+            // add character to current linestring
+            $linestring[$ln] = $char . ((array_key_exists($ln, $linestring)) ? $linestring[$ln] : '');
+        }
+
+        // Handle first line (10nth line or top line of file)
+        if (strpos(end($linestring), '/api/v1/tracks') !== false && strpos(end($linestring), $ip) !== false && strpos(end($linestring), 'HTTP/1.1" 200') !== false){
+            array_push($output, explode( ']', explode( '[', end($linestring) )[1])[0]);
+        }
+        fclose($file);
+        $time_one_hour_before = time() - 3600;
+        if (count($output) < 10 || strtotime(end($output)) < $time_one_hour_before ){
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Return true if content type is one of the following content type: 
+     * application/json, application/ld+json, application/xml, text/csv.
+     * Else return false
+     *
+     * @param string $content_type
+     * @return boolean
+     */
+    public static function contentTypeIsAllowed(string $content_type){  
+        $allowed_content_types = array('application/json', 'application/ld+json', 'application/xml', 'text/csv');
+
+        if (!empty($content_type) && is_string($content_type) && in_array($content_type, $allowed_content_types)){
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Converts body into array depending on content type.
+     * Allowed content types application/json, application/ld+json, application/xml, text/csv
+     * Returns the converted array or false if body not in the expected format.
+     *
+     * @param string $body
+     * @param string $content_type
+     * @return array
+     */
+    public static function readBodyByContentType($body, $content_type){
+        $result;
+        try {
+            if ($content_type === 'application/json' || $content_type === 'application/ld+json'){
+                $result = json_decode($body, true);
+            } 
+            elseif ($content_type === 'application/xml') {
+                $xml = simplexml_load_string($body);
+                $json = json_encode($xml);
+                $result = json_decode($json, true);
+            }
+            elseif ($content_type === 'text/csv') {
+                $lines = explode("\n", $body);
+                $keys = explode(",", $lines[0]);
+                $values = explode(",", $lines[1]);
+                $result = array();
+                for ($x = 0; $x < count($keys); $x++){               
+                    $result[$keys[$x]] = $values[$x];
+                }
+            }
+            else {
+                // This is redundant because contentTypeIsAllowed($request->headers) should be called before this function
+                $result = array();
+            }
+
+            return is_array($result) ? $result : array();
+
+        } catch (\Exception $e){
+            // Reading error
+            error_log($e->getMessage());
+            return array();
+        }
+    }
+
+    /**
+     * Converts $data from array to right format.
+     * Returns false if $data invalid
+     *
+     * @param string $content_type
+     * @return string
+     */
+    public static function convertDataByContentType($content_type, $data){
+        if ($content_type === 'application/json' || $content_type === 'application/ld+json'){
+            return json_encode($data);
+        } 
+        elseif ($content_type === 'application/xml') {
+            return Utils::arrayToXml($data);
+        }
+        elseif ($content_type === 'text/csv') {
+            if (array_keys($data) !== range(0, count($data) - 1)){
+                return Utils::str_putcsv(array($data));                  
+            }
+            else {
+                return Utils::str_putcsv($data);
+            }                 
+        }                 
+        else {
+            // This is redundant because contentTypeIsAllowed($request->headers) should be called before this function
+            return false;
+        }
+    }
+
+    /**
+     * 3rd party code taken from https://www.kerstner.at/2011/12/php-array-to-xml-conversion/
+     *
+     * @param array $array the array to be converted
+     * @param string? $rootElement if specified will be taken as root element, otherwise defaults to <root>
+     * @param SimpleXMLElement? if specified content will be appended, used for recursion
+     * @return string XML version of $array
+     */
+    private static function arrayToXml($array, $rootElement = null, $xml = null) {
+      $_xml = $xml;
+
+      if ($_xml === null) {
+        $_xml = new \SimpleXMLElement($rootElement !== null ? $rootElement : '<root/>');
+      }
+
+      foreach ($array as $k => $v) {
+        if (is_array($v)) { //nested array
+          Utils::arrayToXml($v, $k, $_xml->addChild($k));
+        } else {
+          $_xml->addChild($k, $v);
+        }
+      }
+
+      return $_xml->asXML();
+    }
+
+    /**
+     * 3rd party code taken from https://coderwall.com/p/zvzwwa/array-to-comma-separated-string-in-php
+     *
+     * Convert a multi-dimensional, associative array to CSV data
+     * @param  array $data the array of data
+     * @return string       CSV text
+     */
+    private static function str_putcsv($data) {
+            # Generate CSV data from array
+            $fh = fopen('php://temp', 'rw'); # don't create a file, attempt
+                                             # to use memory instead
+            # write out the headers
+            fputcsv($fh, array_keys(current($data)));
+
+            # write out the data
+            foreach ( $data as $row ) {
+                    fputcsv($fh, $row);
+            }
+            rewind($fh);
+            $csv = stream_get_contents($fh);
+            fclose($fh);
+
+            return $csv;
+    }
+}

vesseltracker/api/model/Database.php

@@ -0,0 +1,34 @@
+<?php 
+
+namespace api\model;
+use PDO;
+
+class Database {
+
+    protected $conn;
+    protected $sqlresult;
+
+    // DB Connect
+    protected function connect($dbsettings) {
+        try{
+            $this->conn = new PDO('mysql:host=' . $dbsettings['host'] . ';dbname=' . $dbsettings['name'], $dbsettings['username'], $dbsettings['password']);
+            $this->conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);  
+        } catch(\PDOException $e) {
+            $this->conn = null;
+            error_log($e->getMessage());
+        }
+        return;
+    }
+
+    // Send query
+    protected function execute($query) {
+        // TODO - check sql injection for all API calls
+        try { 
+            $this->sqlresult = $this->conn->prepare($query);
+            $this->sqlresult->execute();
+        } catch(\PDOException $e) {
+            $this->sqlresult = null;
+            error_log($e->getMessage());
+        }
+    }
+}