How to get refreshed token from Google Calendar API - php

Question

My goal is to retrieve events from google calendar in cron function, I need to do that without authorizing the requests every 1 hour since the access token expires.
From many related stack overflow questions I understood that in the beginning I gain an access token from authorizing the request, then the token get written in a token.json file. After the first access, every time I need to access the calendar the function fGetClient control if the token is expired or not, IF I PREVIOUSLY SET
$client->setAccessType('offline');
the function should refresh the token and i should access the calendar's event without authorizing any further request.
My problem is that i can't get the refreshed token, it expires in an hour and then i need to manually copy the link ,authorize the request and then copy and paste the verification code.
I leave the code below.
public function fGoogleCalendar($operazione=null){
//require_once $this->config["googlecalendardir"].'vendor/autoload.php';
// Get the API client and construct the service object.
$client = $this->fGCGetClient();
$service = new Google_Service_Calendar($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);
$events = $results->getItems();
if (empty($events)) {
$aEventi="0 events found";
} else {
// "Upcoming events:\n";
foreach ($events as $event) {
$start = $event->start->dateTime;
if (empty($start)) {
$start = $event->start->date;
}
$end = $event->end->dateTime;
if (empty($end)) {
$end = $event->end->date;
}
$aEventi[]=array(
"nome" => $event->getSummary(),
"startdate" => $start,
"enddate" => $end
);
$start);
}
}
return $aEventi;
}
public function fGCGetClient(){
require_once $this->config["googlecalendardir"].'vendor/autoload.php';
$client = new Google_Client();
//die("ok");
$client->setApplicationName('Google Calendar API PHP Quickstart');
$client->setScopes(Google_Service_Calendar::CALENDAR_READONLY);
$client->setAuthConfig($this->config["googlecalendardir"].'credentials.json');
$client->setAccessType('offline');
//$client->setApprovalPrompt('auto');
$client->setPrompt('consent');
// Load previously authorized token from a file, if it exists.
// The file token.json stores the user's access and refresh tokens, and is
// created automatically when the authorization flow completes for the first
// time.
$tokenPath = $this->config["googlecalendardir"].'token.json';
if (file_exists($tokenPath)) {
$accessToken = json_decode(file_get_contents($tokenPath), true);
$client->setAccessToken($accessToken);
}
// If there is no previous token or it's expired.
//if (true) {
if ($client->isAccessTokenExpired()) {
// Refresh the token if possible, else fetch a new one.
if ($client->getRefreshToken()) {
//$client->fetchAccessTokenWithRefreshToken($client->getRefreshToken());
$client->fetchAccessTokenWithRefreshToken($client->getRefreshToken());
$client->setAccessToken($client->getAccessToken());
} 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);
$client->setAccessToken($accessToken);
// Check to see if there was an error.
if (array_key_exists('error', $accessToken)) {
throw new Exception(join(', ', $accessToken));
}
}
// Save the token to a file.
if (!file_exists(dirname($tokenPath))) {
mkdir(dirname($tokenPath), 0700, true);
}
file_put_contents($tokenPath, json_encode($client->getAccessToken()));
}
return $client;
}

Answer 1

if you follow php quick start you will notice that it request offline access this means that the first time the user authorizes this application that the refresh token will be returned its then stored in $tokenPath
<?php
require __DIR__ . '/vendor/autoload.php';
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('Google Calendar API PHP Quickstart');
$client->setScopes(Google_Service_Calendar::CALENDAR_READONLY);
$client->setAuthConfig('credentials.json');
$client->setAccessType('offline');
$client->setPrompt('select_account consent');
// Load previously authorized token from a file, if it exists.
// The file token.json stores the user's access and refresh tokens, and is
// created automatically when the authorization flow completes for the first
// time.
$tokenPath = 'token.json';
if (file_exists($tokenPath)) {
$accessToken = json_decode(file_get_contents($tokenPath), true);
$client->setAccessToken($accessToken);
}
// If there is no previous token or it's expired.
if ($client->isAccessTokenExpired()) {
// Refresh the token if possible, else fetch a new one.
if ($client->getRefreshToken()) {
$client->fetchAccessTokenWithRefreshToken($client->getRefreshToken());
} 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);
$client->setAccessToken($accessToken);
// Check to see if there was an error.
if (array_key_exists('error', $accessToken)) {
throw new Exception(join(', ', $accessToken));
}
}
// Save the token to a file.
if (!file_exists(dirname($tokenPath))) {
mkdir(dirname($tokenPath), 0700, true);
}
file_put_contents($tokenPath, json_encode($client->getAccessToken()));
}
return $client;
}
// 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);
$events = $results->getItems();
if (empty($events)) {
print "No upcoming events found.\n";
} else {
print "Upcoming events:\n";
foreach ($events as $event) {
$start = $event->start->dateTime;
if (empty($start)) {
$start = $event->start->date;
}
printf("%s (%s)\n", $event->getSummary(), $start);
}
}

Answer 2

In your current directory delete this file token.json
It's where the token is saved if you delete the file your program won't find the token therefore create a new token.