GET

Get one or multiple entities from the Datastore. Retrieving an entity by key is the fastest way to read from the Datastore. This method accepts the following arguments:

MyModel.get(
    /* {int|string|Array<int|string>}. -- id(s) to retrieve */
    <id>,
    /* {Array} -- optional. ex: ['ParentEntity', 1234 ] */
    <ancestors>,
    /* {string} -- optional. A specific namespace */
    <namespace>,
    /* {Transaction} -- optional. The transaction currently in progress */
    <transaction>,
    /* {object} -- optional. Additional config */
    <options>,
    /* {function} -- optional. The callback, if not passed a Promise is returned */
    <callback>
)

@Returns -- a gstore entity instance.

Example:

const BlogPost = require('./blog-post.model');

// id can be an integer or a string
BlogPost.get(123).then((entity) => {
    console.log(entity.plain());
});

// Array of ids
BlogPost.get([1,2,3]).then((entities) => {
    entities = entities.map(entity => entity.plain());
});

// Passing an ancestor path with a Kind and a name
const ancestors = ['Parent', 'parentName'];
BlogPost.get('stringId', ancestors).then((entity) => { ... });

// ... with a callback
BlogPost.get(1234, function onEntity(err, entity) {
    if (err) { // deal with err }
    console.log('Blogpost title:', entity.title);
});

The resulting entity has a plain() method that returns an object with the entity data + its id. See the doc here.

BlogPost.get(123).then(entity) {
    console.log(entity.plain());
});

If you need to retrieve an entity from inside a transaction, you can pass the transaction object as fourth parameter.

const transaction = gstore.transaction();

transaction.run().then(() => {
    BlogPost.get(123, null, null, transaction)
            .then((entity) => {
                // Reminder: entity is an instance of the BlogPost model with all its properties & methods

                transaction.commit().then(() => { ... });
            });
});

options properties

• preserveOrder (default: false)

• dataloader: a Dataloader instance

• cache (default: true)

• ttl (default: the global cache ttl.keys configuration)

> preserveOrder: This option is useful when you pass an array of IDs to retrieve and you want to preserve the order of those ids in the response.

Note: setting this property to true does add some processing, especially for large sets. Only use it if you absolutely need to maintain the original order passed.

> dataloader The Dataloader instance created for the request. Read the documentation for more information on how to create the instance.

> cache If you activated the cache on the gstore-node instance, you can override here the global cache configuration. If the global has been set to true (default) you can pass false here to bypass the cache. And if the global cache has been set to false, then you can pass true here to cache specific key(s).

> ttl Overrides the global keys TTL of the cache. If you have multiple cache stores, you can pass an Object with a different value for each store. See in the example below.

const gstore = require('gstore-node')();

// Important! This should be done on **each** request (read the Dataloader documentation)
const dataloader = gstore.createDataLoader();

BlogPost.get([1,2,3], null, null, null, { preserveOrder: true, dataloader })
        .then((entities) => {
            // Order is preserved
            console.log(entities[0].entityKey.id); // 1
            console.log(entities[1].entityKey.id); // 2
            console.log(entities[2].entityKey.id); // 3
        });

// cache ttl options example
BlogPost.get(123, null, null, null, { ttl: 300 })
        .then(() => ... );

// cache ttl multi stores
BlogPost.get(123, null, null, null, { ttl: { memory: 60, redis: 900 } })
        .then(() => ... );