How to create a public Google Doc through the Drive API (PHP client)

Question

This is what I've got so far, by combining this and this:

require_once "google-api-php-client/src/Google_Client.php";
require_once "google-api-php-client/src/contrib/Google_DriveService.php";
require_once "google-api-php-client/src/contrib/Google_Oauth2Service.php";

//First, build a Drive service object authorized with the service accounts
$auth = new Google_AssertionCredentials(
    DRIVE_SERVICE_ACCOUNT_EMAIL,
    array( DRIVE_SCOPE ),
    file_get_contents( DRIVE_SERVICE_ACCOUNT_KEY )
);
$client = new Google_Client();
$client->setUseObjects( true );
$client->setAssertionCredentials( $auth );
$service = new Google_DriveService( $client );

//Then, insert the file
$file = new Google_DriveFile();
$file->setTitle( 'My document' );
$file->setMimeType( 'text/plain' );
$createdFile = $service->files->insert( $file, array(
    'data' => 'Hello world!',
    'mimeType' => 'text/plain',
));

print_r( $createdFile );

It works, meaning that it creates a text/plain file and returns me an array with its metadata. However, what I want is to create a Google Document, not a text/plain. I tried of course changing the mime type (both appearances) to "application/vnd.google-apps.document", but got the following:

Fatal error: Uncaught exception 'Google_ServiceException' with message 'Error calling POST https://www.googleapis.com/upload/drive/v2/files?uploadType=multipart: (400) Bad Request' in /local/path/to/google-api-php-client/src/io/Google_REST.php:66

Also, I need the document to be publicly accessible. When I upload a text/plain file through the above method, and then try to browse to it (from an account different of the uploader's), I'm told that I need permission. I took a closer look at the array in $createdFile and noticed a 'shared' key with no value, so quite naively I tried setting it to 1 with:

$file->setShared( 1 );

It didn't work, and also, when I looked again at the array, I noticed that the 'shared' key had still no value assigned to it. I looked online for any documentation that may help me, but no luck. Anyone can help me out? Thanks!!

Answer 1

After much reading and testing, I found the answer to my question.

The problem was the 'data' parameter of the file: the Google Docs cannot have plain text as data (their data needs to include some headers or something). So by deleting the 'data' parameter (and the 'mimeType' too, why not), the error I got disappeared.

As to the permissions, the solution was to first create the file with the default permissions, and then add a new one.

Below I paste the minimal code to create a publicly accessible Google Doc:

require_once "google-api-php-client/src/Google_Client.php";
require_once "google-api-php-client/src/contrib/Google_DriveService.php";
require_once "google-api-php-client/src/contrib/Google_Oauth2Service.php";

//Build the Drive Service object authorized with your Service Account
$auth = new Google_AssertionCredentials(
    DRIVE_SERVICE_ACCOUNT_EMAIL,
    array( DRIVE_SCOPE ),
    file_get_contents( DRIVE_SERVICE_ACCOUNT_KEY )
);
$client = new Google_Client();
$client->setUseObjects( true );
$client->setAssertionCredentials( $auth );
$service = new Google_DriveService( $client );

//Create the file
$file = new Google_DriveFile();
$file->setTitle( 'Hello world!' );
$file->setMimeType( 'application/vnd.google-apps.document' );
$file = $service->files->insert( $file );

//Give everyone permission to read and write the file
$permission = new Google_Permission();
$permission->setRole( 'writer' );
$permission->setType( 'anyone' );
$permission->setValue( 'me' );
$service->permissions->insert( $file->getId(), $permission );

print_r( $file );

Answer 2

I have implemented this as a plugin in the Moodle LMS system, here is the source code, which includes a PHP class that implement creating and setting proper permissions to the docs. https://github.com/nadavkav/moodle-mod_googledrive

The actual relevant class is here: https://github.com/nadavkav/moodle-mod_googledrive/blob/master/classes/googledrive.php