Use

The can/map behavior links a connection to a DefineMap and DefineList type. The connection will create those types of instances from the data it receives. It also adds convenient methods and observable values to the Map that offer connection functionality (e.g instance.save) and the status of the instance (e.g instance.isSaving).

To use the can/map behavior, first create a Map and List constructor function:

var Todo = DefineMap.extend({
  allowComplete: function(ownerId) {
    return this.ownerId === ownerId;
  }
});

var TodoList = DefineList.extend({
  "#": Todo,
  incomplete: function(){
    return this.filter({complete: false});
  }
});

Next, pass the Map and List constructor functions to connect as options. The following creates connects the Todo and TodoList types to a RESTful data service via the connection:

import connect from "can-connect";
import dataUrl from "can-connect/data/url/url";
import constructor from "can-connect/constructor/constructor";
import canMap from "can-connect/can/map/map";

const todoConnection = connect( [ dataUrl, constructor, canMap ], {
    Map: Todo,
    List: TodoList,
    url: "/services/todos"
} );

The connection itself can be used to create, read, update & delete Todo and TodoLists:

todoConnection.getList( {} ).then( function( todos ) {
    const incomplete = todos.incomplete();
    incomplete[ 0 ].allowComplete( 5 ); //-> true
} );

... or instead of how it's done above, because can/map adds methods to the Map type, you can use Todo to retrieve Todo and TodoLists:

Todo.getList( {} ).then( function( todos ) { /* ... */ } );
Todo.get( {} ).then( function( todo ) { /* ... */ } );

You can also create, update, and destroy Todo instances. Notice that save is used to create and update:

// create an instance
new Todo( { name: "dishes" } ).save().then( function( todo ) {
    todo.set( {
        name: "Do the dishes"
    } )
        .save() // update an instance
        .then( function( todo ) {
            todo.destroy(); // destroy an instance
        } );
} );

There's also methods that let you know if an instance is in the process of being saved or destroyed:

const savePromise = new Todo( { name: "dishes" } ).save();
todo.isSaving(); //-> true

savePromise.then( function() {
    todo.isSaving(); //-> false

    const destroyPromise = todo.destroy();
    todo.isDestroying(); //-> true

    destroyPromise.then( function() {
        todo.isDestroying(); //-> false
    } );
} );