Update website via google spreadsheets

gsx_db_web.php

<?php 

/**
 * @see https://www.reddit.com/r/PHP/comments/7wu9w5/gsx_db_update_your_website_data_instantly_with_a/
 */

class Gsx_db {

	var $google_page_id;
	var $tables;

	function __construct($spreadsheet_url) {	
		$this->google_page_id = $this->make_google_id_from_url($spreadsheet_url);
		$this->load_tables();	
	}	

	protected function load_tables(){
		//Get all worksheets in the spreadsheet 
		$url = "https://spreadsheets.google.com/feeds/worksheets/".$this->google_page_id."/public/full?alt=json";
		$json = file_get_contents($url);
		$json_decoded = json_decode($json,true);
		//the useful rows
		$array_worksheets = $json_decoded['feed']['entry'];

		$worksheets = array();
		foreach ($array_worksheets as $worksheet) {
				$worksheet_title = $worksheet['title']['$t']; 
				$url = $worksheet['link'][0]['href'] . "?alt=json"; //select the first option (xml), but ask specifically for the json format

				$worksheets[] = array(
					'title' => $worksheet_title,
					'url' => $url
				); 
		}
		$this->tables = $worksheets;
	}



	public function get_table_by_title($title){

		$all_entries=array();

		//loop through all the tables, and check if the requested title matches one.
		for ($i=0; $i < count($this->tables); $i++) { 

			$table = $this->tables[$i];
			if($table['title'] == $title){
				$json = file_get_contents($table['url']);
				$json_decoded = json_decode($json,true);

				//the sorta useful bits
				$entries = $json_decoded['feed']['entry'];

				//Match found...

				foreach ($entries as $rows) {
		
					$return_row = array();

					foreach ($rows as $key => $value) {
						if(!isset($value['$t'])){ continue; } //No data for this row. Skipping.

						$value = $value['$t']; 
						//google uses the dollar sign to delineate the first row of headings

						if(strpos($key,'$')>0){ //if theres a dollar sign, it is one of our defined headings.

							$key = substr($key,4); //chop off the first four characters ' gsx$ ' to define the key
				
							$return_row += array(
								$key => $value
							);
						}
					}
					$result[] = $return_row;
				}
				return $result;
			}
		}
	}

	public function list_tables(){
		return $this->tables;
	}

	public function make_human_readable_key($key){
		$key = str_replace("-"," ",$key);
		$key = ucwords($key);
		return $key;
	}


	public function make_google_id_from_url($spreadsheet_url){
		$strpos = strpos($spreadsheet_url,"/d/") + 3;   //Remove everything from the front of the ID
		$spreadsheet_url = substr($spreadsheet_url, $strpos); 
		$strstr = strstr($spreadsheet_url, "/", true); //Return everything before the first remaining / character
		return $strstr;
	}

}