manager.fetchMetadata() error in breeze - breeze

Question

My goal is to create new entity of a new type and push it to manager.
I've created new entity type:
var newType = new breeze.EntityType({
shortName: "input"
});
To be able to create new entity of this type I need to fetch metadata first:
var entityManager = new breeze.EntityManager('api/Db');
entityManager.fetchMetadata(success, failed);
function success(){
var newEntity = entityManager.createEntity('input', {});
}
function failed(){}
The problem is that I have an error on the line entityManager.fetchMetadata(): "TypeError: Cannot call method 'then' of undefined"
Why I'm seeing this error?
does fetchMetadata() tries to http: GET metadata from somewhere? I don't have it anywhere.. How to create the metadata then?
UPDATE:
following suggestions I've rewrite code into:
//create new entity type
var newType = new breeze.EntityType({
shortName: "input",
autoGeneratedKeyType: breeze.AutoGeneratedKeyType.KeyGenerator
});
//add property
var info = new breeze.DataProperty({
name: "text",
dataType: breeze.DataType.String,
isNullable: true,
isPartOfKey: true,
maxLength: 20
});
newType.addProperty(info);
//create metadata on fly
var metadataStore = new breeze.MetadataStore();
metadataStore.addEntityType(newType);
var dataService = new breeze.DataService({
serviceName: 'isdataservice',
hasServerMetadata: false
});
var entityManager = new breeze.EntityManager({
dataService: dataService,
metadataStore: metadataStore
});
//create entry
var entity = entityManager.createEntity('input', { name: "nnn" });

Answer 1

Breeze metadata is information about all the objects you have to work with. You can fetch metadata from server-side or you can create metadata by yourself and work with it.
If you want to work with your server-side objects in breeze you create an entity manager with var entityManager = new breeze.EntityManager('api/Db'); where api/db is your asp.net controller. This controller should have a Metadata() method which returns repository.Metadata(). In js you call entityManager.fetchMetadata().then(success, failed); After the promise of fetchMetadata() is resolved, breeze metadata of variable entityManager is full-filled and you can start working with your server-side objects in js with breeze!
But you can also work without any metadata from server-side and create it on the fly in your js code. You create your own metadataStore, attach it to entitymanager. Pseudo code:
var myMetadataStore = new breeze.MetadataStore();
myMetadataStore.addEntityType({...});
var dataService = new breeze.DataService({
serviceName: 'demo',
hasServerMetadata: false
});
var entityManager = new breeze.EntityManager({
dataService: dataService,
myMetadataStore: store
});
var entity = manager.createEntity(...);
Here is a working sample from breeze with on-the-fly metadata http://www.breezejs.com/breeze-labs/breezedirectivesvalidation
You click on code button or just go to http://plnkr.co/edit/lxPAbIJmRaLmyagXQAFC?p=info to see sources
Also take a look at this link in breeze docs http://www.breezejs.com/documentation/metadata