Code to create Api key in PHP.

 An API key is used by a lot of Web API to provide a form of access control. The key usually is linked to the identity of the API user as well as bundle of rights like a quota or areas of the APIs which are open for access to that key

Example::

<?php


// get the HTTP method, path and body of the request

$method = $_SERVER['REQUEST_METHOD'];

$request = explode('/', trim($_SERVER['PATH_INFO'],'/'));

$input = json_decode(file_get_contents('php://input'),true);


// connect to the mysql database

$link = mysqli_connect('localhost', 'root', 'root', 'myDB');

mysqli_set_charset($link,'utf8');


// retrieve the table and key from the path

$table = preg_replace('/[^a-z0-9_]+/i','',array_shift($request));

$key = array_shift($request)+0;


// escape the columns and values from the input object

$columns = preg_replace('/[^a-z0-9_]+/i','',array_keys($input));

$values = array_map(function ($value) use ($link) {

  if ($value===null) return null;

  return mysqli_real_escape_string($link,(string)$value);

},array_values($input));


// build the SET part of the SQL command

$set = '';

for ($i=0;$i<count($columns);$i++) {

  $set.=($i>0?',':'').'`'.$columns[$i].'`=';

  $set.=($values[$i]===null?'NULL':'"'.$values[$i].'"');

}


// create SQL based on HTTP method

switch ($method) {

  case 'GET':

    $sql = "select * from `myform`".($key?" WHERE id=$key":''); break;

  case 'PUT':

    $sql = "update `myform` set $set where id=$key"; break;

  case 'POST':

    $sql = "insert into `myform` set $set"; break;

  case 'DELETE':

    $sql = "delete `myform` where id=$key"; break;

}


// excecute SQL statement

$result = mysqli_query($link,$sql);


// die if SQL statement failed

if (!$result) {

  http_response_code(404);

  die(mysqli_error());

}


// print results, insert id or affected row count

if ($method == 'GET') {

  if (!$key) echo '[';

  for ($i=0;$i<mysqli_num_rows($result);$i++) {

    echo ($i>0?',':'').json_encode(mysqli_fetch_object($result));

  }

  if (!$key) echo ']';

} elseif ($method == 'POST') {

  echo mysqli_insert_id($link);

} else {

  echo mysqli_affected_rows($link);

}


// close mysql connection


mysqli_close($link);

?>