The Google Sheets PHP connector

This is the PHP version of the RGraph Google Sheets connector library. Use it if you want to hide the fact that you're using Google Sheets or if you have server-side code that needs to connect to a Google Sheets spreadsheet.

It's written in PHP but if you need to convert it to a different coding language it should be quite readable code for you to do so. 

<?php
    // o--------------------------------------------------------------------------------o
    // | This file is part of the RGraph package - you can learn more at:               |
    // |                                                                                |
    // |                         https://www.rgraph.net                                 |
    // |                                                                                |
    // | RGraph is licensed under the Open Source MIT license. That means that it's     |
    // | totally free to use and there are no restrictions on what you can do with it!  |
    // o--------------------------------------------------------------------------------o
    
    // Version 1.03

    class RGraph_Sheets
    {
        // The key of the spreadsheet
        public $key;

        // The data of the spreadsheet
        public $data;

        // Your OAuth ID
        public $oauth;

        // The worksheet ID
        public $worksheet = 'Sheet1';

        // Used for the columnn names.
        public $letters = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';

        // The URL of the sheet
        public $url = 'https://sheets.googleapis.com/v4/spreadsheets/[KEY]/values/[WORKSHEET]?alt=json&key=[OAUTH_KEY]';




        //
        // The constructor that creates the object
        //
        // @param string $key The identifier of the spreadsheet. You can get this
        //                    out of the URL for the spreadsheetsheet.
        //
        public function __construct ($oauth, $key = '', $worksheet = 'Sheet1')
        {
            $this->oauth     = $oauth;
            $this->key       = $key;
            $this->worksheet = $worksheet;

            // Do this if the key is a file: URL
            if (substr($this->oauth, 0, 5) === 'file:') {
                $filename = substr($this->oauth, 5);
                $this->json_raw = file_get_contents($filename);

            } else {
                // Add the key and worksheet ID into the URL
                $this->url = preg_replace('/\[OAUTH_KEY\]/', $this->oauth, $this->url);
                $this->url = preg_replace('/\[KEY\]/', $this->key, $this->url);
                $this->url = preg_replace('/\[WORKSHEET\]/', urlencode($this->worksheet), $this->url);

                // Fetch the sheet
                $this->json_raw = file_get_contents($this->url);
            }

            // Get rid of comments
            //$this->json = trim(preg_replace('|// API callback|m','',$this->json_raw));

            // Get rid of the JSONP function call
            //$this->json = preg_replace('/^__callback__\(/','',$this->json);
            //$this->json = preg_replace('/\);$/','',$this->json);

            // Convert the JSON into a PHP object
            $this->json = json_decode($this->json_raw);


            // Pull the data out of the json variable
            $grid = [];
            $row  = 0;
            $col  = 0;

            for ($row=0; $row<count($this->json->values); ++$row) { // Loop thru each row
                for ($col=0;$col<count($this->json->values[$row]); $col++) {
                    $grid[$row][$col] = $this->json->values[$row][$col];
                }
            }

            //
            // Determine the longest row
            //
            $maxcols = 0; // The max length of the rows
            
            for ($i=0; $i<count($grid); ++$i) {
                $maxcols = $grid[$i] ? max($maxcols, count($grid[$i]) ) : $maxcols;
            }


            //
            // Go through the array and fill in any blank holes.
            //
            for ($i=0; $i<count($grid); ++$i) {
                
                if (!$grid[$i]) {
                    $grid[$i] = array();
                    
                    // TODO Might need to add a loop setting the $maxcols number of
                    // array elements to a blank string.
                }

                for ($j=0; $j<$maxcols; $j++) {
                    if (empty($grid[$i][$j])) {
                        $grid[$i][$j] = '';
                    }
                    
                    ksort($grid[$i]);
                    
                    // Convert numbers to real numbers and floats here too
                    if (is_numeric($grid[$i][$j])) {
                        $grid[$i][$j] = (float)$grid[$i][$j];
                    }
                }
            }

            $this->numcols = $maxcols;
            $this->numrows = count($grid);
            $this->data    = $grid;
            ksort($this->data);
        }








        //
        // Fetches a row of data and returns it
        //
        // @param $index number The numeric index of the row to fetch (starts at 1)
        // @param $start number The number of columns that should be fetched
        // @param $opt          An option array containing options (optional)
        //
        public function row ($index, $start = 1)
        {
            $index = (int)$index;
            $start = (int)$start;
            
            if ($index === 0) {
                $index = 1;
                // 08/12/2020
                // Removed due to PHP 8 upgrade
                //
                //trigger_error('The row number given was zero - however row numbers begin at 1');
            }
            
            if ($this->data[$index - 1]) {
                $row = array_slice($this->data[$index - 1], $start - 1);
                return $row;
            } else {
                return [];
            }
        }







        //
        // Fetches a column of data and returns it
        //
        // @param $index number The letter that pertains to the column to fetch
        // @param $start number The number of rows that should be fetched
        // @param $opt          An option array containing options (optional)
        //
        public function col ($index, $start = 1)
        {

            for ($i=0,$col=[]; $i<count($this->data); ++$i) {
                $col[] = $this->data[$i][$index - 1];
            }

            // Now account for the start index
            $col = array_slice($col, $start - 1);

            return $col;
        }








        //
        // Returns the index (zero index) of the given letters
        //
        public function getIndexOfLetter  ($letter)
        {
            $letter = strtoupper($letter);

            if (strlen($letter) > 1) {            
                $parts = array_slice(preg_split('//', trim($letter)), 1, -1);
            } else {
                $parts = array($letter);
            }

            // Two letters are possible ie A -> ZZ
            if (count($parts) === 1) {
                return strpos($this->letters, $letter) + 1;
            
            } else if (count($parts) === 2){

                $idx =   ((strpos($this->letters, $parts[0]) + 1) * 26)
                       + (strpos($this->letters, $parts[1]) + 1);

                return $idx;
            }
        }








        //
        // The get() method makes retrieving cells very straightforward,
        // for example: obj.get('B1');
        //
        // @param str string The cells(s) to fetch
        // @param     string Optional set of options that are passed
        //                   to the relevant row/col function
        //
        function get ($str, $opt = [])
        {
            // Uppercase letters please!
            $str = strtoupper(trim($str));
            $ret = []; // This is the array that gets returned

            //
            // Handle the style of get('C') or get('AA'
            //
            if (preg_match('/^[A-Z]+$/', $str)) {
                if (strlen($str) === 1) {
                    $index = strpos($this->letters, $str) + 1;
                    $ret = $this->col($index, 1, $opt);
                
                } else if (strlen($str) === 2) {

                    $index = ((strpos($This->letters, $str[0]) + 1) * 26) + strpos($this->letters, $str[1]) + 1;
                    $ret = $this->col($index, 1, $opt);
                }
            }




            //
            // Handle the style of get('2');
            //(fetching a whole row
            //
            if (preg_match('/^[0-9]+$/i', $str)) {
                $ret = $this->row($str, 1, $opt);
            }




            //
            // Handle the style of get('E2');
            //(fetching a single cell)
            //
            if (preg_match('/^([a-z]{1,2})([0-9]+)$/i', $str, $matches)) {
                
                $letter = $matches[1];
                $number = (int)$matches[2];
                $col    = $this->get($letter);

                $ret = $col[$number - 1];
            }




            //
            // Handle the style of .get('B2:E2');
            //(fetching the B2 cell to the E2 cell)
            //
            if (preg_match('/^([a-z]{1,2})([0-9]+)\s*:\s*([a-z]{1,2})([0-9]+)$/i', $str, $matches)) {

                $letter1 = $matches[1];
                $number1 = $matches[2];
                $letter2 = $matches[3];
                $number2 = $matches[4];

                // A column
                if ($letter1 === $letter2) {
                    $cells = [];
                    $index = $this->getIndexOfLetter($letter1);

                    $col = $this->col($index, 1, $opt);

                    for ($i=($number1 - 1); $i<$number2; ++$i) {
                        $cells[] = !empty($col[$i]) ? $col[$i] : '';
                    }

                // A row
                } else if ($number1 === $number2) {

                    $cells  = [];
                    $row    = $this->row($number1, 1, $opt);
                    $index1 = $this->getIndexOfLetter($letter1);
                    $index2 = $this->getIndexOfLetter($letter2);

                    for ($i=($index1 - 1); $i<=($index2 - 1); ++$i) {
                        $cells[] = $row[$i];
                    }

                // A matrix
                } else if ($letter1 !== $letter2 AND $number1 !== $number2) {

                    $cells  = [];
                    $row    = [];
                    $index1 = $this->getIndexOfLetter($letter1);
                    $index2 = $this->getIndexOfLetter($letter2);

                    for ($i=$number1; $i<=$number2; ++$i) {
                        $row = $this->row($i);
                        $row = array_slice(
                            $row,
                            $index1 - 1,
                            $index2 - $index1 + 1
                        );
                        $cells[] = $row;
                    }
                }

                $ret = $cells;
            }
            
            // If the option has been specified then encode the array as a string
            if (!empty($opt['string'])) {
                $ret = json_encode($ret);
            }

            return $ret;
        }
    }
?>