How to share data in breezeJS - breeze

Question

So here's the case i got a product table and a category table, product has a category, now i want to retrieve partial products meaning only select productId, productName and categoryId
then i also retrieve partial Categorys selecting only the categoryName, so far i tried maping the data.results to breeze entitys for both the category results and the product results but how to share data between them?
For example i want to be able to do this:
<section data-bind="foreach: Product">
<article data-bind="text: productName"></article>
<article data-bind="text: category().categoryName"></article>
</section>
The mapping logic
function mapDtosToEntities(manager, dtos, entityName, keyName, extendWith) {
return dtos.map(dtoToEntityMapper);
function dtoToEntityMapper(dto) {
var keyValue = dto[keyName];
var entity = manager.getEntityByKey(entityName, keyValue);
if (!entity) {
// We don't have it, so create it as a partial
extendWith = $.extend({ }, extendWith || defaultExtension);
extendWith[keyName] = keyValue;
entity = manager.createEntity(entityName, extendWith);
}
mapToEntity(entity, dto);
entity.entityAspect.setUnchanged();
return entity;
}
function mapToEntity(entity, dto) {
// entity is an object with observables
// dto is from json
for (var prop in dto) {
if (dto.hasOwnProperty(prop)) {
entity[prop](dto[prop]);
}
}
return entity;
}
}
The reason for this is that i got 2 views one that display products and one that displays categories, in the products view i need some category info and i don't want to hit the server twice to get the same data for both views i want to be able to share that data between them.
Note: I am working with durandal don't know if that would matter.

Answer 1

For future reference if any one got the same problem the following
sample will help you.
In this sample i am using northwind as a real example on how to accomplish this.
javascript
var EntityQuery = breeze.EntityQuery,
manager = configureBreezeManager();
var defaultExtension = { IsPartial: true };
function configureBreezeManager() {
breeze.NamingConvention.camelCase.setAsDefault();
var mgr = new breeze.EntityManager('api/northwind');
mgr.metadataStore.registerEntityTypeCtor(
'Category', function () { this.IsPartial = false; });
mgr.metadataStore.registerEntityTypeCtor(
'Product', function () { this.IsPartial = false; });
return mgr;
}
var model = function(){
this.Products = ko.observableArray([]);
};
var modelInstance = new model();
function mapDtosToEntities(mgr, dtos, entityName, keyName, extendWith) {
return dtos.map(dtoToEntityMapper);
function dtoToEntityMapper(dto) {
var keyValue = dto[keyName];
var entity = mgr.getEntityByKey(entityName, keyValue);
if (!entity) {
// We don't have it, so create it as a partial
extendWith = $.extend({ }, extendWith || defaultExtension);
alert(JSON.stringify(extendWith))
extendWith[keyName] = keyValue;
alert(JSON.stringify(extendWith));
entity = mgr.createEntity(entityName, extendWith);
}
mapToEntity(entity, dto);
entity.entityAspect.setUnchanged();
return entity;
}
function mapToEntity(entity, dto) {
for (var prop in dto) {
if (dto.hasOwnProperty(prop)) {
entity[prop](dto[prop]);
}
}
return entity;
}
}
var query = new EntityQuery()
.from("Products")
.select("productID, productName, categoryID");
var queryx = new EntityQuery()
.select("categoryID, categoryName")
.from("Categories");
manager.executeQuery(queryx)
.then(querySucceededx)
.fail(function(error){ alert(error + "queryx"); });
function querySucceeded(data) {
var list = mapDtosToEntities(manager, data.results, "Product", "productID");
modelInstance.Products(list);
}
function querySucceededx(data) {
var list = mapDtosToEntities(manager, data.results, "Category", "categoryID");
manager.executeQuery(query)
.then(querySucceeded)
.fail(function(error){ alert(error + "query"); });
}
ko.applyBindings(modelInstance);
html
<ul data-bind="foreach: Products">
<li>
<span data-bind="text: productID"></span>
<span data-bind="text: productName"></span> ---
<span data-bind="text: category().categoryName"></span>
</li>
</ul>
Mapping will work on id matching breeze is smart enough to figure out the relationship and share the data with the product entity.