Concept of LinkHandler

LinkHandler represent Links to resources like videos, search requests, channels, etc. The idea behind them is that a video can have multiple links pointig to it, but it has one unique id that represents it, like this example:

oHg5SJYRHA0 can be represented as:

• https://www.youtube.com/watch?v=oHg5SJYRHA0 (default url for youtube)
• https://youtu.be/oHg5SJYRHA0
• https://m.youtube.com/watch?v=oHg5SJYRHA0

Importand notes about LinkHandler:

• A simple LinkHandler will contain the default URL, the ID and the original url.
• LinkHandler are ReadOnly
• LinkHandler are also used to determine which part of the extractor can handle a certain link.
• In order to get one you must either call fromUrl() or fromId() of the the coresponding LinkHandlerFactory.
• Every type of Type of Resource has its own LinkHandlerFactory. Eg. YoutubeStreamLinkHandler, YoutubeChannelLinkHandler, etc.

Usage

So the typical Usage for getting a LinkHandler would look like this.

LinkHandlerFactory myLinkHandlerFactory = new MyStreamLinkHandlerFactory();
LinkHandler myVideo = myLinkHandlerFactory.fromUrl("https://my.service.com/the_video");

Implementation

In order to Use LinkHandler for your service you must override the apropriate LinkHandlerFactory. eg:

class MyStreamLinkHandlerFactory extends LinkHandlerFactory {

    @Override
    public String getId(String url) throws ParsingException {
        // Return the ID based on the url.
    }

    @Override
    public String getUrl(String id) throws ParsingException {
        // Return the url based on the id given.
    }

    @Override
    public boolean onAcceptUrl(String url) throws ParsingException {
        // Return true if this LinkHanlderFactory can handle this type of link
    }
}

ListLinkHandler and QueryLinkHandler

List based resources like channels and playlists can be sorted, for example by date, name, or by a certain name. Therefore these type of resources don't just use a LinkHandler, but an extention called ListLinkHandler