Database Reference
In-Depth Information
Filtering Consumption for Users
One practical use of the consumption model is to create a content trail for users, as shown in Figure
12-14
. As a user
clicks on items in the scrolling product stream, the interaction is captured using
createUserView
, which ultimately
returns a
list
of relationship objects of the
VIEWED
type.
In the
Consumption
section, take a look at the c
reateUserProductViewRel
method to see how the process begins
inside the controller. The controller method first saves the view and then returns the complete history of views using
the
getProductTrail method,
which can be found in the Product service class. The process is started when the
createUserProductViewRel
function is called, which is located in
graphstory.js.
Figure 12-14.
The Scrolling Product and Product Trail page
For the sample application, you will use the
addUserViewAndReturnProductTrail
method in the
ProductDAO
class to find the Product entity being viewed and then create an explicit relationship type called
VIEWED
. As you may
have noticed, this is the first instance of a relationship type in the application that contains properties. In this case,
you are creating a timestamp with a
Date
object and String value of the timestamp. The query, provided in
Listing 12-38, checks to see if a
VIEWED
relationship already exists between the user and the product.
If the result of the
MERGE
clause within query is returns zero matches, then a map is created with key value pairs to
create properties on the new relationship, specifically
timestamp
and
dateAsStr
. Otherwise, the query will update the
existing relationship properties to their new, respective values.
