Mike Chambers

I am putting together an ActionScript 2 class to represent and parse Atom feeds. I have put together an early alpha version of the class, but wanted to get some feedback on it before I continue work on it.

Alpha .22: (Feb.12 2004)

• Refactored to make it easier to extend and add support for custom namespaces
• User cannot add nodes
• tag attributes are now placed in attributes object for element.
• TODO: check case sensitivity in switch statements
• TODO: check if namespace is added tags : atom:element
• TODO: optimize parse functions
• TODO: document api
• TODO: wrap in MXP file for distribution

Alpha .20:

• Should parse all elements and attributes described in the Atom .03 spec.
• Does not currently support non-atom namespaces.
• Utilizes the W3CDateTime class

Alpha .10:

• Does not parse all Atom elements.
• Only parses elements included in default Movable Type atom feed. Specifically, my Atom feed.
• Cannot yet add nodes
• Dates are not supported yet. Need to make a date class for the date types used by Atom
• This is a super early version, and the code will probably drastically change.

Before I finish up adding support for all of Atom, I wanted to get some input on the class, and how I make the Atom dom avaliable. Please post any suggestions in the comments.

One quick comment (and my personal opinion), thus far, Atom has been a pure joy to work with. It is so nice have a structured format to work with. I love what RSS enables, but with all of the different versions, and permutations, it is a huge hassle to work with.

Anyways, here is the class (v .20):

[code]/*Atom.asMike Chambersmesh@macromedia.comClass that represents an Atom XML document.You can find more information on Atom at:http://www.atomenabled.orgVersion Alpha .22-user cannot yet add nodes-check case sensitivity in switch statements-check if namespace is added tags : atom:element-optimize parse functions*/import mx.events.EventDispatcher;import com.macromedia.date.W3CDateTime;class com.macromedia.data.Atom extends XML{private var dispatchEvent:Function;public var addEventListener:Function;public var removeEventListener:Function;private var feed:Object;private var entriesArray:Array;private var ignoreWhite:Boolean = true;public function Atom(xmlSource:String){super(xmlSource);mx.events.EventDispatcher.initialize(this);}private function onLoad(success:Boolean):Void{if(!success){//throw errortrace("xml did not load");return;}parseFeedTags();dispatchEvent({type:"onAtomLoad", target:this});}//need a way to reparse if user manually adds nodesprivate function parseFeedTags(Void):Void{feed = parseFeedElement();//should this be in info, or in feed//feed.info = parseFeedElement();var nodes:Array = firstChild.childNodes;var len:Number = nodes.length;var node:XMLNode;for(var i:Number = 0; i< len; i++){node = nodes[i];//do we need to worry about case sensitivity?switch(node.nodeName){case "entry":{break;}case "title":{feed.title = parseFeedTitle(node);break;}case "author":{feed.author = parseFeedAuthor(node);break;}case "contributor":{feed.contributor = parseFeedContributor(node);break;}case "tagline":{feed.tagline = parseFeedTagline(node);break;}case "copyright":{feed.copyright = parseFeedCopyright(node);break;}case "generator":{feed.generator = parseFeedGenerator(node);break;}case "info":{feed.info = parseFeedInfo(node);break;}case "id":{feed.id = parseFeedId(node);break;}case "link":{feed.link = parseFeedLink(node);break;}case "modified":{feed.modified = parseFeedModified(node);break;}default:{parseFeedDefault(node);break;}}}}private function parseFeedTitle(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;return obj;}private function parseFeedAuthor(node:XMLNode):Object{var obj:Object = parsePersonConstruct(node);return obj;}private function parseFeedContributor(node:XMLNode):Object{var obj:Object = parsePersonConstruct(node);return obj;}private function parseFeedTagline(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;return obj;}private function parseFeedCopyright(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;return;}private function parseFeedGenerator(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;var genAtts:Object = node.attributes;obj.url = genAtts.url;obj.version = genAtts.version;return obj;}private function parseFeedInfo(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;return obj;}private function parseFeedId(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;return;}private function parseFeedLink(node:XMLNode):Object{var obj:Object = parseLinkConstruct(node);return obj;}private function parseFeedModified(node:XMLNode):Object{var obj:Object = new Object();obj.value = W3CDateTime.parseString(node.firstChild.nodeValue);return obj;}private function parseFeedDefault(node:XMLNode):Object{return undefined;}private function parseLinkConstruct(node:XMLNode):Object{var feedAtts:Object = node.attributes;var link:Object = new Object();link.attributes = new Object();link.attributes.rel = feedAtts.rel;link.attributes.type = feedAtts.type;link.attributes.href = feedAtts.href;link.attributes.title = feedAtts.title;return link;}private function parseFeedElement(Void):Object{var feedInfo:Object = new Object();feedInfo.attributes = new Object();var feedAttributes:Object = firstChild.attributes;feedInfo.attributes.version = feedAttributes.version;feedInfo.attributes["xml:lang"] = feedAttributes["xml:lang"];return feedInfo;}//need a way to reparse if user manually adds nodesprivate function parseEntries(Void):Void{entriesArray = new Array();var nodes:Array = firstChild.childNodes;var len:Number = nodes.length;var node:XMLNode;var tempEntry:Object;for(var i:Number = 0; i< len; i++){node = nodes[i];if(node.nodeName == "entry"){tempEntry = parseEntry(node);entriesArray.push(tempEntry);}}}private function parseEntry(node:XMLNode):Object{if(node == undefined){return;}var entryElements:Array = node.childNodes;var elementLen:Number = entryElements.length;var entry:Object = new Object();var entryElement:XMLNode;for(var k:Number = 0; k < elementLen; k++){entryElement = entryElements[k];switch(entryElement.nodeName){case "title":{entry.title = parseEntryTitle(entryElement);break;}case "link":{entry.link = parseEntryLink(entryElement);break;}case "modified":{entry.modified = parseEntryModified(entryElement);break;}case "issued":{entry.issued = parseEntryIssued(entryElement);break;}case "id":{entry.id = parseEntryId(entryElement);break;}case "created":{entry.created = parseEntryCreated(entryElement);break;}case "summary":{entry.summary = parseEntrySummary(entryElement);break;}case "author":{entry.author = parseEntryAuthor(entryElement);break;}case "contributor":{entry.contributor = parseEntryContributor(entryElement);break;}case "content":{entry.content = parseEntryContent(entryElement);break;}default:{//pass this to a parse default functionbreak;}}}return entry;}private function parseEntryTitle(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;return obj;}private function parseEntryLink(node:XMLNode):Object{var obj:Object = parseLinkConstruct(node);return obj;}private function parseEntryModified(node:XMLNode):Object{var obj:Object = new Object();obj.value = W3CDateTime.parseString(node.firstChild.nodeValue);return obj;}private function parseEntryIssued(node:XMLNode):Object{var obj:Object = new Object();obj.value = W3CDateTime.parseString(node.firstChild.nodeValue);return obj;}private function parseEntryId(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;return obj;}private function parseEntryCreated(node:XMLNode):Object{var obj:Object = new Object();obj.value = W3CDateTime.parseString(node.firstChild.nodeValue);return obj;}private function parseEntrySummary(node:XMLNode):Object{var obj:Object = new Object();obj.value = node.firstChild.nodeValue;obj.type = node.attributes.type;var childNodes:Array = node.childNodes;var childNodesLen:Number = childNodes.length;var childNode:XMLNode;//TODO: test this with a summary tag//find out if there is a created nodefor(var z:Number = 0; z < childNodesLen; z++){childNode = childNodes[z];if(childNode.nodeName == "created"){obj.created = new Object();obj.created.value =W3CDateTime.parseString(childNode.firstChild.nodeValue);break;}}return obj;}private function parseEntryAuthor(node:XMLNode):Object{var obj:Object = parsePersonConstruct(node);return obj;}private function parseEntryContributor(node:XMLNode):Object{var obj:Object = parsePersonConstruct(node);return obj;}private function parseEntryContent(node:XMLNode):Object{var obj:Object = new Object();obj.attributes = new Object();var atts:Object = node.attributes;obj.attributes.mode = atts.mode;obj.attributes.type = atts.type;obj.value = node.firstChild.nodeValue;return obj;}private function parsePersonConstruct(node:XMLNode):Object{var author:Object = new Object();var children:Array = node.childNodes;var len:Number = children.length;var tempNode:Object;var tempName:String;for(var i:Number = 0; i < len; i++){tempNode = children[i];tempName = tempNode.nodeName;switch(tempName){case "name":{//fall through}case "url":{//fall through}case "email":{author[tempName] = new Object();author[tempName].value = tempNode.firstChild.nodeValue;break;}}}return author;}/**************** Public API / Getters *******************///TODO: make sure we have getters for all of the top level feed elementspublic function getFeedTitle(Void):String{return feed.title.value;}public function getFeedModified(Void):Date{return feed.modified.value;}public function getFeedLink(Void):Object{return feed.link;}public function getFeedId(Void):String{return feed.id.value;}public function getFeedGenerator(Void):String{return feed.generator.value;}public function getFeedCopyright(Void):String{return feed.copyright.value;}public function getFeedTagline(Void):String{return feed.tagline.value;}//TODO : should this be a property?public function getFeed(Void):Object{return feed;}public function get entries ():Array{if(entriesArray == undefined){parseEntries();}return entriesArray;}}[/code]