# Creation

Each entity is an instance of a Model and represents an entity stored in the Datastore of a certain _Kind_.\
To create an entity you call the Model constructor

```javascript
new Model(
    /* {object} -- The entity data to be saved */
    <data>,
    /* {int|string}. -- optional. The id of the entity.
                        If not passed the Datastore will automatically 
                        generate a random one
     */
    <id>,
    /* {Array} -- optional. Ancestors of the entity. ex: ['ParentEntity', 1234 ] */
    <ancestors>,
    /* {string} -- optional. A specific namespace */
    <namespace>
)

example:
const blogPost = new BlogPost({title: 'title of the post', author: 'John Snow' });
```

## id

**(optional)**

By default, if you don't pass an id when you create an instance, the entity id will be auto-generated. If you want to manually give the entity an id, pass it as a second parameter during the instantiation.

```javascript
// String id
const blogPost = new BlogPost(data, 'stringId');

// Integer ir
const blogPost = new BlogPost(data, 1234);
```

If the ID integer is **outside the bounds of a JavaScript Number object**, you have to create an **Int** calling the int() method from @google-cloud/datastore

Reminder: _gstore.ds_ is an alias to the google-cloud **datastore** instance.

```javascript
// long Key ID 
const blogPost = new BlogPost(data, gstore.ds.int('100000000000001234'));
```

## ancestors

**(optional)**

You can define the ancestors of the entity.

```javascript
// Auto generated id with an ancestor
const blogPost = new BlogPost(data, null, ['Parent', 'keyname']);

// Manual id on an ancestor
const blogPost = new BlogPost(data, 1234, ['Parent', 'keyname']);
```

## namespace

**(optional)**

By default entities keys are generated with the default namespace (defined when setting up the '@google-cloud/datastore'). You can create models instances on another namespace by passing it as a third parameter.

```javascript
// Creates an entity with auto-generated id on the namespace "dev-com.my-domain"
const blogPost = new BlogPost(data, null, null, 'dev.com.my-domain');
```
