manager.fetchMetadata() error in 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