Google Calendar Server to Server - fullcalendar

Question

I use to make appointments a calendar based on FULLCALENDAR with backup of the rdv in a database mysql on my own local server. So far, so good. I wish I could synchronize the rdvs thus taken, on the google calendar and inversely be able to import into my database mysql the rdvs taken on the account of google on line.
I tried to understand and read the API doc of google calendar here and here
I only get error messages.
I tried to do it directly in fullcalendar but the calendar must be declared in public, something I can not do.
The ideal would be to be able to make server calls in php (login and password of google clandier backup in local mysql database), for which I create my API key and a service account, but again I do not get only error messages.
Would there be a link or a really functional tutorial that I could use to learn
I tried with this link but never succeeded
thanks in advance.
EDIT : I try this.
quickstart.php
<?php
require_once __DIR__ . '/vendor/autoload.php';
define('APPLICATION_NAME', 'Google Calendar API PHP Quickstart');
define('CREDENTIALS_PATH', '~/.credentials/calendar-php-quickstart.json');
define('CLIENT_SECRET_PATH', __DIR__ . '/client_id.json');
// If modifying these scopes, delete your previously saved credentials
// at ~/.credentials/calendar-php-quickstart.json
define('SCOPES', implode(' ', array(
Google_Service_Calendar::CALENDAR_READONLY)
));
if (php_sapi_name() != 'cli') {
throw new Exception('This application must be run on the command line.');
}
/**
* Returns an authorized API client.
* #return Google_Client the authorized client object
*/
function getClient() {
$client = new Google_Client();
$client->setApplicationName(APPLICATION_NAME);
$client->setScopes(SCOPES);
$client->setAuthConfig(CLIENT_SECRET_PATH);
$client->setAccessType('offline');
// Load previously authorized credentials from a file.
$credentialsPath = expandHomeDirectory(CREDENTIALS_PATH);
if (file_exists($credentialsPath)) {
$accessToken = json_decode(file_get_contents($credentialsPath), true);
} else {
// Request authorization from the user.
$authUrl = $client->createAuthUrl();
printf("Open the following link in your browser:\n%s\n", $authUrl);
print 'Enter verification code: ';
$authCode = trim(fgets(STDIN));
// Exchange authorization code for an access token.
$accessToken = $client->fetchAccessTokenWithAuthCode($authCode);
// Store the credentials to disk.
if(!file_exists(dirname($credentialsPath))) {
mkdir(dirname($credentialsPath), 0700, true);
}
file_put_contents($credentialsPath, json_encode($accessToken));
printf("Credentials saved to %s\n", $credentialsPath);
}
$client->setAccessToken($accessToken);
// Refresh the token if it's expired.
if ($client->isAccessTokenExpired()) {
$client->fetchAccessTokenWithRefreshToken($client->getRefreshToken());
file_put_contents($credentialsPath, json_encode($client->getAccessToken()));
}
return $client;
}
/**
* Expands the home directory alias '~' to the full path.
* #param string $path the path to expand.
* #return string the expanded path.
*/
function expandHomeDirectory($path) {
$homeDirectory = getenv('HOME');
if (empty($homeDirectory)) {
$homeDirectory = getenv('HOMEDRIVE') . getenv('HOMEPATH');
}
return str_replace('~', realpath($homeDirectory), $path);
}
// Get the API client and construct the service object.
$client = getClient();
$service = new Google_Service_Calendar($client);
// Print the next 10 events on the user's calendar.
$calendarId = 'primary';
$optParams = array(
'maxResults' => 10,
'orderBy' => 'startTime',
'singleEvents' => TRUE,
'timeMin' => date('c'),
);
$results = $service->events->listEvents($calendarId, $optParams);
if (count($results->getItems()) == 0) {
print "No upcoming events found.\n";
} else {
print "Upcoming events:\n";
foreach ($results->getItems() as $event) {
$start = $event->start->dateTime;
if (empty($start)) {
$start = $event->start->date;
}
printf("%s (%s)\n", $event->getSummary(), $start);
}
}
php quickstart.php
PHP Fatal error: Uncaught InvalidArgumentException: missing the required redirect URI in /Users/krislec/Desktop/vendor/google/auth/src/OAuth2.php:648
Stack trace:
#0 /Users/krislec/Desktop/vendor/google/apiclient/src/Google/Client.php(340): Google\Auth\OAuth2->buildFullAuthorizationUri(Array)
#1 /Users/krislec/Desktop/quickstart.php(36): Google_Client->createAuthUrl()
#2 /Users/krislec/Desktop/quickstart.php(75): getClient()
#3 {main}
thrown in /Users/krislec/Desktop/vendor/google/auth/src/OAuth2.php on line 648
Fatal error: Uncaught InvalidArgumentException: missing the required redirect URI in /Users/krislec/Desktop/vendor/google/auth/src/OAuth2.php:648
Stack trace:
#0 /Users/krislec/Desktop/vendor/google/apiclient/src/Google/Client.php(340): Google\Auth\OAuth2->buildFullAuthorizationUri(Array)
#1 /Users/krislec/Desktop/quickstart.php(36): Google_Client->createAuthUrl()
#2 /Users/krislec/Desktop/quickstart.php(75): getClient()
#3 {main}
thrown in /Users/krislec/Desktop/vendor/google/auth/src/OAuth2.php on line 648