How to generate entity id for GAE datastore in php? - php

Question

i am trying to insert new entity using PHP client library into datastore, i am using datastore_connect.php file from this example, https://github.com/amygdala/appengine_php_datastore_example
I want to insert entity with auto id, not the name. I see that there is function setId(), but i dont know how to generate proper id. Whats the best practice in doing so?
Thanks
function createKeyForTestItem () {
$path = new Google_Service_Datastore_KeyPathElement();
$path->setKind("testkind");
$path->setName("testkeyname");
//$path->setId(??)
$key = new Google_Service_Datastore_Key();
$key->setPath([$path]);
return $key;
}

Answer 1

You can have Cloud Datastore generate the ID for you by populating the insertAutoId field on the mutation instead of the upsert field.
Here's a code snippet (adapted from the datastore_connect.php file you posted):
function create_key() {
$path = new Google_Service_Datastore_KeyPathElement();
$path->setKind("testkind");
// Neither name nor ID is set.
$key = new Google_Service_Datastore_Key();
$key->setPath([$path]);
return $key;
}
function create_entity() {
$entity = new Google_Service_Datastore_Entity();
$entity->setKey(create_key());
// Add properties...
return $entity;
}
function create_commit_request() {
$entity = create_entity();
$mutation = new Google_Service_Datastore_Mutation();
$mutation->setInsertAutoId([$entity]); // Causes ID to be allocated.
$req = new Google_Service_Datastore_CommitRequest();
$req->setMode('NON_TRANSACTIONAL');
$req->setMutation($mutation);
return $req;
}

Answer 2

If you're looking for a PHP library to take away most of the headache of Cloud Datastore, you could try my new library, which sits on top of the official google-api-php-client:
https://github.com/tomwalder/php-gds
And here's a sample code snippet to create an Entity with an auto-generated ID
$obj_book = new GDS\Entity();
$obj_book->title = 'Romeo and Juliet';
$obj_book->author = 'William Shakespeare';
$obj_book->isbn = '1840224339';
// Write it to Datastore
$obj_book_store->upsert($obj_book);
More code snippets and documentation on GitHub.