AJAX - The Complete Reference

442 Part II: Developing an Ajax Library^

request.template is the URL of the template of interest and is appended to the request

payload (query string or message body) so that the server can render the response. We will

need to make sure that the server program is defined with this in mind. We could also set

template: dynamic and templateRender: server, but this would be the standard

method that is employed in a server-side program so there is nothing for the client library

to do here.

Summary of Library Template Mechanism

We present a brief summary of each template mechanism in Table 9-1 as an overview.

We have also provided a simple Template Explorer program for you to play with at

http://ajaxref.com/ch9/templateexplorer.html, with the general idea of the example shown

in Figure 9-6.

Applied Templates

Architecturally, templates certainly can clean things up quite a bit. As we have shown, if the

application is well designed, the presentation layer can be elegantly broken out into an Ajax

and non-Ajax approach and even switch back and forth. Templates also may have some

other value in that they provide a degree of flexibility. For example, consider how we might

extend our rating widget to display a different response template depending on the type of

Template

Specified By

Render

Location Description Example

Client Client Library fetches given

template file. When response

and template file return, it

processes the output.

http://ajaxref.com/ch9/templatecc.html

Client Server Library sends the URL of the

template to the server in

the payload with a name of

templateURL.

http://ajaxref.com/ch9/templatecs.html

Server

(returning

URL and

template

string)

Client Server generates both the

template contents as well

as the URL key it should be

stored as in the template

cache. These are passed

back in the JSON packet

as templateText and

templateURL.

http://ajaxref.com/ch9/templatesc3.html

Server

(returning

URL)

Client Server generates the URL

and passes it back as part

of the JSON packet as

templateURL. The library

then sends a synchronous

request to get the template

and caches the results.

http://ajaxref.com/ch9/templatesc2.html

TABLE 9-1 Summary of Template Usage Patterns