flex360 milan 2008 - flex & webservices

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Flex 3 & Webservices

Cristian Ivascu :: Adobe360 Flex, Milan08 – APR - 2008

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Agenda

Introduction to Flex and web services Building a SOAP-based app REST services Building a del.icio.us based app Q&A

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One server, multiple, disparate clients

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What are webservices?

Practice matters!

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W3C says: “a software system designed to support interoperable Machine to Machine interaction over a network” (W3C)

In practice:web apis that are accessed remotely

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Web services – which one?

SOAP & WSDL Machine usable Verbose Enterprise

REST Light-weight No encoding popular!

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Flex and Webservices

Flex creates rich clients; Web services bring data to the client Flex works with web services in an easy

manner

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WSDL sample - VideoSearch

• Only one operation• Simple request parameters• Slightly complex response

• Link: http://localhost/video.wsdl

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How to access the service?

At runtime At development time (via tool support)

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Runtime Demo

Let’s see it in the Builder!

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When to use it• Dynamic scenarios• Discovery of services at run-time• Services that may change more often

Characteristics• Not tied to a particular implementation• Very flexible• Adapts easily to changes, without messing with the code

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What about this?

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Dev-time way

Why?• For the more static scenarios – build and forget• For increased productivity• To make it easier

How?• Added classes to model the wsdl contents• Added a way to link types in wsdl to AS classes• Tool support & code generation

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Video Search Demo redone

The same Video Searching app re-done to take advantage of the new features.,

Let’s see how it’s made.

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Generated code – is this spaghetti?

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How to find and fix problems

Check if the schema is there Breakpoints in call() and processResult() Check type mappings & wsdl type

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Known issues with the generated code

We don’t support everything – only WS-I 1.0 profile; wsdl 1.0 & soap 1.1

Known issues – there are a few Have one? Report it @ bugs.adobe.com/flex

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REST

Can use multiple output formats – XML, JSON, etc

Is very light-weight Pro: performance Con: there is no typing info!

Is very popular

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Flex & Rest services

They haven’t change much AS allows manipulation of XML and binding to objects But there’s a catch – httpservice.xmlDecode() + a custom

model

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DEMO – del.icio.us API usage

xmlDecode to convert raw xml into an array of “Post.as” instances

There is also a more generic approach – using SimpleXMLDecoder & ObjectTranslator

http://booleanbetrayal.com/2007/05/18/httpservice-xmldecode-objecttranslator-and-rabidsquirrels/

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Copyright 2008 Adobe Systems Incorporated. All rights reserved.

Flex | Final words of wisdom

Web services are a way of getting data into your Flex app; When building rich clients you need to use them Web services in Flex can be better; for suggestions or bugs

visit: bugs.adobe.com/flex

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Q & A

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• Flex can cope with both dynamic and strong-typed web service usage.• The wizard only generates some code for you. Tweak it!• Strong types are not for WSDL only. Use XMLDecode() .

This is (almost) the last slide

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Go play!

http://adobe.com/go/flex

…and off to lunch! Buon appetito!

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