Manifest Handling

Everything MPD-related lives in the dash/ layer. The rest of the player never touches the parsed manifest directly.

Loading and parsing

ManifestLoader downloads the MPD (applying request interceptors and retry logic from the net/ stack) and hands it to the parser (dash/parser/), which converts the XML into a JavaScript object tree, resolving inheritance (Period → AdaptationSet → Representation), xlink references and SegmentTemplate/SegmentTimeline structures.

The DashAdapter facade

DashAdapter is the single point of access to the parsed manifest for the streaming layer:

• The streaming layer asks DashAdapter for StreamInfo (periods), MediaInfo (tracks) and Representation objects — plain value objects that are independent of the MPD structure.
• Rule: streaming code must not reach into the raw parsed MPD. If a new piece of manifest data is needed, it is exposed through DashAdapter and the value objects. This keeps the manifest format encapsulated in one layer (and is what allows the mss/ module to feed Smooth Streaming manifests into the same pipeline).

Live updates

For dynamic MPDs, ManifestUpdater refreshes the manifest periodically — the refresh interval comes from MPD@minimumUpdatePeriod and can be tuned via settings. Instead of full reloads, servers can also publish incremental updates via MPD Patching. When the manifest changes, updated StreamInfo/MediaInfo objects propagate through DashAdapter and the pipeline adjusts — new periods are added, finished ones removed, and a dynamic-to-static transition ends the live session (see Live Streaming).

Segment request generation

DashHandler translates "give me the next segment for this Representation" into a concrete URL and byte range — resolving SegmentTemplate placeholders, walking SegmentTimeline entries, or using SegmentBase index ranges. It is the only place where segment addressing schemes are implemented.