實作自訂內容解析器

您可以根據預設解析器來實作您自己的內容解析器。

當TVSDK偵測到新的商機時，它會逐一檢視註冊的內容解析器，尋找一個能夠使用 canResolve 方法。 系統會選取第一個傳回true的來解析商機。 如果沒有任何內容解析程式能夠解析內容，則會略過該機會。 由於內容解析程式通常是非同步的，內容解析程式負責在程式完成時通知TVSDK。

• 內容解析器呼叫 client.place 以指定TVSDK需要執行的時間表操作（通常是廣告插播位置）。
• 內容解析器呼叫 client.notifyCompleted 如果解決流程成功，或 client.notifyFailed 如果處理失敗。

1. 建立自訂機會解析程式。

   public class CustomResolver extends ContentResolver {
   
       /**
        * Default constructor.
        */
       public function CustomResolver() {
       }
   
       override protected function doConfigure(item:MediaPlayerItem):void {
           // here you can read any media stream characteristics which
           // might help configure your content resolver like
           // - the media player item configuration through the item.config
           // - the media resource metadata through item.resource.metadata
       }
   
       /**
        * @inheritDoc
        */
       override protected function doCanResolve(opportunity:Opportunity):Boolean {
           // check if the opportunity can be resolved by this resolver
           // if yes return true, otherwise return false
   
           return true;
       }
   
       /**
        * @inheritDoc
        */
       override protected function doResolve(opportunity:Opportunity):void {
           // start the resolving process
           // communicate with your custom ad server
   
           // in this example we assume that:
           // - if successful, onResolveCompleted method will be invoked
           // - if failed, onResolveFailed method will be invoked
       }
   
       private function onResolveCompleted(response:*):void {
           try {
               var proposals:Vector.<TimelineOperation> = new Vector.<TimelineOperation>();
   
               // extract the timeline ad placement from the response
               // and add them to the proposal vector
               // - extract the ad break
               // - calculate the placement ( can reuse the opportunity.placement )
               // var timelineOperation:AdBreakPlacement = new AdBreakPlacement(placement, adBreak);
               // proposals.push(timelineOperation);
   
               client.process(proposals);
               client.notifyCompleted(_opportunity);
           } catch (error:Error) {
               onResolveFailed(error);
           }
       }
   
       private function onResolveFailed(error:Error):void {
   
           var errorMetadata:Metadata = new Metadata();
           MetadataUtils.serializeError(error, errorMetadata);
   
           var mediaError:MediaError = new MediaError(NotificationCode.CONTENT_RESOLVING_ERROR, errorMetadata);
           client.notifyFailed(_opportunity, mediaError);
       }
   
       ...
   }
   

2. 建立使用自訂內容解析程式的自訂內容處理站。

   例如：

   public class CustomContentFactory extends DefaultContentFactory {
           ...
   
           /**
            * @inheritDoc
            */
           override protected function
             doRetrieveResolvers(item:MediaPlayerItem):Vector.<ContentResolver> {
               var result:Vector.<ContentResolver> = new Vector.<ContentResolver>();
   
               var resource:MediaResource = item.resource;
   
               if (resource.metadata != null) {
                   if (resource.metadata.containsKey(DefaultMetadataKeys.AUDITUDE_METADATA_KEY)) {
                       result.push(new AuditudeAdResolver());
                   } else if (resource.metadata.containsKey("custom-opportunity-detector")) {
                       result.push(new CustomResolver());
                   }
               }
               return result;
           }
   }
   

3. 註冊要播放的媒體資料流的自訂內容處理站。

   例如：

   var mediaPlayerItemConfig:MediaPlayerItemConfig = new DefaultMediaPlayerItemConfig();
   mediaPlayerItemConfig.advertisingFactory = new CustomContentFactory();
   ...
   
   var advertisingMetadata:AdvertisingMetadata = new AdvertisingMetadata();
   // set any parameter you need for custom ad resolver
   // advertisingMetadata.setValue("customparam", "customvalue");
   
   var metadata:Metadata = new Metadata();
   metadata.setMetadata("custom-opportunity-detector", advertisingMetadata);
   var mediaResource:MediaResource = MediaResource.createFromUrl(url, metadata);
   
   player.replaceCurrentResource(mediaResource, mediaPlayerItemConfig);