Consuming Amazon with Flash Remoting
Pages: 1, 2
Connecting with Flash Remoting
Now it's time to open Flash MX and build the framework for our application. For this application to properly run, you need to install Flash Remoting on your Web server. A 30-day trial version of Flash Remoting is available for download from Macromedia.
In Flash MX, create a new Flash File and open the action's dialog for frame 1. In this frame we will use Flash Remoting to create a connection to Amazon.com's XML Web Service.
#include "NetServices.as"
init( init== null )
{
var init = true;
NetServices.setDefaultGatewayURL(
"http://localhost/flashremoting/services/gateway.aspx" );
gatewayConnection = NetServices.createGatewayConnection();
AmazonWebService = gatewayConnection.getService(
"http://soap.amazon.com/schemas/AmazonWebServices.wsdl", this );
}I've created a code block that initializes my XML Web Service. The first line of the code snippet grabs additional functions and objects included with Flash Remoting from an external action script file. Within the code block we need to define the location of our server using the gateway and instance of the XML Web Service. My application uses the WSDL address we discussed earlier to access Amazon.com's XML Web Service, this allows Flash Remoting to programmatically build a proxy, or interrupter, to our XML Web Service.
This code snippet is for a ASP.Net server; a JRun or Coldfusion server will not require .aspx on the gateway call. Also, ASP.Net requires a physical file in the path; JRun and Coldfusion don't.
Building the Interface
With a connection to our XML Web Service established, let's build a interface to display the output.
Using the text tool, create two text boxes on the main movie clip. Name the first text box txtName and the second txtPrice. Next, create an empty movie clip named mcImage and place it on your main movie clip. Please note that our mcImage movie clip will work as a holder for our product's image. Because the size of the image varies based on the type of product, it's a good idea to add a backdrop for your movie clip. For more information on dynamically loading images view my article on jasonmperry.com.
With our base elements in place you may want to add a little spice to your Amazon.com product spotlight. I've taken the liberty of adding a bright spinning background to draw attention to the spotlighted book and setting my text colors to white.
Manipulating the XML Web Service
Interface in hand, lets focus on filling those text boxes with dynamic
content. To do this we need to implement a callback function and object
that wraps to our XML Web Service's <message> and
<xsd:complexType> definitions.
function AsinSearchRequest_Result( result )
{
ProductInfo = result;
//sets the product info for our moviec lip
txtProductName.text = ProductInfo.Details[ 0 ].ProductName;
txtProductPrice.text = ProductInfo.Details[ 0 ].OurPrice;
urlProductLocation = ProductInfo.Details[ 0 ].Url;
//loads the medium sized image onto the _root.
//Image holder provides size holder.
loadMovie( ProductInfo.Details[ 0 ].ImageUrlMedium, _root.mcImage );
}
function AsinSearchRequest_Status( error )
{
trace( error.code );
trace( error.description );
trace( error.details );
}Callback functions receive response data and errors sent from our XML
Web Service proxy. These callbacks wrap to the
AsinSearchRequest function defined in the WSDL. The
"_Result" function is called with the output of
AsinSearchResponse, and "_Status" is called if an
error occurs during the call. When implementing a callback function take
the name of the method and add both "_Result" and
"_Status" to the end. In our "_Result" callback
we receive an instance of the ProductInfo type defined in our
WSDL. Our code snippet grabs the returned product's name, price, URL, and
image from the result.
We also need to use loadMovie to dynamically grab the URL
of our product's image and display it in our Flash Application. To provide
better positioning of the image you should use load the jpeg into a movie
clip.
//creates a AsinRequest object type wrapper
asinRequest = function(asin, mode)
{
this.asin = asin;
this.mode = mode;
this.tag = "webservices-20"; //tag
this.token = "???"; //Your unique token
this.version = "1.0"; //id of this version of Amazon service. Currently 1.0.
this.type = "heavy"; //"heavy" or "lite" determines amount of copy returned
}
Object.registerClass( "AsinRequest", asinRequest );The next step is to create a object wrapper for our parameter type. To
do this we can create mirror image of our AsinRequest WSDL
complex type as a Flash object. We also need to register the new class as
type AsinRequest.
AmazonWebService.AsinSearchRequest( new AsinRequest( "0672320789", "books") );With our callbacks done and AsinRequest object registered, we can call
the AsinSearchRequest method and sent our
AsinRequest parameter to the XML Web Service. When Flash
Remoting receives data as ether a error message or result it will call the
proper callback function.
NOTE: When in debug mode you can view the result data to see the best way to access the data.
In the sample download I've taken the liberty of implementing the remaining callback functions and wrappers. This should give you a good idea of how to implement any object in Flash based on its WSDL counterpart.
Conclusion
Using Flash Remoting to create a dynamic interface to Amazon.com's XML Web Services only brushes on the capabilities of Flash Remoting. The true potential lies in developing Flash interfaces that mimic Windows UI components and are responsive. In the near future, complex applications like credit card accounts will allow you to drag and drop a payment onto the proper icon or display a progress bar as it grabs last month's statement.
The FLA source file built in this tutorial is available for download as FlashAmazonSpotlight.zip. Note the file will not work with out Flash Remoting installed and running on your computer. A 30-day trial version of Flash Remoting is available for download at Macromedia.com.
Jason Michael Perry is a partner in Out the Box Web Productions and the Webmaster for Pan-American Life, an international financial services company. You can contact Jason by visiting Jasonmperry.com.
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Showing messages 1 through 4 of 4.
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CFMX Version please
2003-02-26 03:32:39 anonymous2 [View]
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respond this topic
2010-05-18 04:38:55 LeslieRaymond21 [View]
I had a dream to begin my own organization, nevertheless I did not have enough amount of cash to do it. Thank goodness my close friend said to take the home loans (http://lowest-rate-loans.com/topics/home-loans) . Thus I used the commercial loan and made real my dream.
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The example does not work with CFMX
2003-02-19 10:57:34 anonymous2 [View]
As noted in the prior comment, the example only works with the .Net implementation of remoting (a shame really). I have tried countless ways to get it working with the CFMX server but no such luck. I get a huge java compilation error returned to the output window.
If the author could write a specific CFMX instance of the tutorial, it would be appreciated.
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Challenges for newcomers and many typos
2003-01-19 14:31:53 anonymous2 [View]
Folks, I appreciate the article topic and the generally useful info shared by the author, but I have a couple of concerns. Since some may point to this as a good intro to using Flash to do web services, it seems worth pointing out some challenges, especially for those looking at Flash for the first time.
Sadly that article falls victim to the mistake many such "intro to flash remoting" articles do--presuming too much Flash understanding by the reader.
It says "create a new Flash File and open the action's dialog for frame 1", but if you don't know how to do that, or even what a frame is, you're lost at that point. Later it says "Using the text tool, create two text boxes on the main movie clip." Again, if one doesn't know how to use that tool, let alone what is meant by a movie, they'll be lost.
Of course, the info is valuable to those with a little more experience, but even then as an O'Reilly resource, it's shocking how many typos and otherwise challenging aspects there are:
- brick and motor placement firms (mortar)
- as if it where its own (were)
- build a Flash spotlight that dynamically list (lists)
- and we'll use to provide (use it to)
- to know about a XML (an XML)
- the elements wrap to the ("wrap to" doesn't seem to make sense. what is meant in this context? Perhaps simply "wrap"? See also "object that wraps to our XML Web Service's" and "callbacks wrap to the AsinSearchRequest")
- build a proxy, or interrupter, to our XML Web Service (interpreter?)
- for a ASP.Net server (an ASP.Net)
- let's build a interface (an interface)
- creates a AsinRequest (an AsinRequest)
- you should use load the jpeg (strike use?)
- we can call the AsinSearchRequest method and sent our AsinRequest (send)
It might also have been helpful to define ASIN somewhere (which is Amazon's identification number used as an alternative to ISBNs).
And while the article concludes that "the file will not work with out Flash Remoting installed and running on your computer", it should more technically add that this specific example won't work unless one is using ASP.NET. Again, for newcomers, it might have been helpful to at least point out that all would be needed would be to change the value for setDefaultGatewayURL, as well as perhaps show values that would have worked for CF and J2EE servers.
In the case of CFMX users, for instance, we would want to change that line to:
NetServices.setDefaultGatewayURL( "http://localhost:8500/flashservices/gateway" );
assuming the user is running CFMX with the built-in web server, or leave off the port for those using CFMX with an external web server.
One last concern: the error handling function only writes Trace statements rather than offering any feedback in the flash movie itself. This becomes more important because my attempts to use the code as is failed (after applying my own Amazon developer token and changing to point to my own CF server with flash remoting installed). The error indicated that:
Web service operation "AsinSearchRequest" ...could not be found
It may be that this is more a bug in CFMX's ability to process the web service as provided by Amazon (there seem to be some sensitivities about its support for some web services, perhaps due to the stub generation that CF does for us). If any other readers figure out what CF folks need to do get it working (even in just a CFINVOKE as a test), I'm sure many readers would appreciate it.
Again, I don't mean to knock the article entirely. There is lots of useful info for folks. It's just that for those coming to it on recommendations from others, they should know of some of the challenges (and hopefully I've saved someone the effort who would have wanted to post these same observations).
Even so, I'm sure other readers may disagree with some of my assertions. I look forward to further discussions.
/charlie
it would be appreciated. Flash Remoting has great capabilities yet undiscovered.