dash parser work in progress

happydom.ts

@@ -1,3 +1,5 @@
 import { GlobalRegistrator } from "@happy-dom/global-registrator";
 
-GlobalRegistrator.register();
+const oldConsole = console;
+GlobalRegistrator.register();
+window.console = oldConsole;

src/dash-parser/examples/mpd.ts

@@ -1,28 +1,27 @@
-export const testString = `<?xml version="1.0" encoding="UTF-8"?><MPD xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" maxSubsegmentDuration="PT5.0S" mediaPresentationDuration="PT9M57S" minBufferTime="PT5.0S" profiles="urn:mpeg:dash:profile:isoff-on-demand:2011,http://xmlns.sony.net/metadata/mpeg/dash/profile/senvu/2012" type="static" xsi:schemaLocation="urn:mpeg:dash:schema:mpd:2011 DASH-MPD.xsd">
-  <Period duration="PT9M57S" id="P1">
-  <!-- Adaptation Set for main audio -->
-  <AdaptationSet audioSamplingRate="48000" codecs="mp4a.40.5" contentType="audio" group="2" id="2" lang="en" mimeType="audio/mp4" subsegmentAlignment="true" subsegmentStartsWithSAP="1">
-    <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
-    <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
-    <Representation bandwidth="64000" id="2_1">
-      <BaseURL>DASH_vodaudio_Track5.m4a</BaseURL>
-    </Representation>
-  </AdaptationSet>
-  <!-- Adaptation Set for video -->
-  <AdaptationSet codecs="avc1.4D401E" contentType="video" frameRate="24000/1001" group="1" id="1" maxBandwidth="1609728" maxHeight="480" maxWidth="854" maximumSAPPeriod="5.0" mimeType="video/mp4" minBandwidth="452608" minHeight="480" minWidth="854" par="16:9" sar="1:1" subsegmentAlignment="true" subsegmentStartsWithSAP="1">
-    <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
-    <Representation bandwidth="1005568" height="480" id="1_1" mediaStreamStructureId="1" width="854">
-      <BaseURL>DASH_vodvideo_Track2.m4v</BaseURL>
-    </Representation>
-    <Representation bandwidth="1609728" height="480" id="1_2" mediaStreamStructureId="1" width="854">
-      <BaseURL>DASH_vodvideo_Track1.m4v</BaseURL>
-    </Representation>
-    <Representation bandwidth="704512" height="480" id="1_3" mediaStreamStructureId="1" width="854">
-      <BaseURL>DASH_vodvideo_Track3.m4v</BaseURL>
-    </Representation>
-    <Representation bandwidth="452608" height="480" id="1_4" mediaStreamStructureId="1" width="854">
-      <BaseURL>DASH_vodvideo_Track4.m4v</BaseURL>
-    </Representation>
-  </AdaptationSet>
-  </Period>
-  </MPD>`;
+export const testString = `<?xml version="1.0" encoding="utf-8"?>
+<MPD mediaPresentationDuration="PT634.566S" minBufferTime="PT2.00S" profiles="urn:hbbtv:dash:profile:isoff-live:2012,urn:mpeg:dash:profile:isoff-live:2011" type="static" xmlns="urn:mpeg:dash:schema:mpd:2011" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:mpeg:DASH:schema:MPD:2011 DASH-MPD.xsd">
+<BaseURL>./</BaseURL>
+<Period>
+ <AdaptationSet mimeType="video/mp4" contentType="video" subsegmentAlignment="true" subsegmentStartsWithSAP="1" par="16:9">
+  <SegmentTemplate duration="120" timescale="30" media="$RepresentationID$/$RepresentationID$_$Number$.m4v" startNumber="1" initialization="$RepresentationID$/$RepresentationID$_0.m4v"/>
+  <Representation id="bbb_30fps_1024x576_2500k" codecs="avc1.64001f" bandwidth="3134488" width="1024" height="576" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_1280x720_4000k" codecs="avc1.64001f" bandwidth="4952892" width="1280" height="720" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_1920x1080_8000k" codecs="avc1.640028" bandwidth="9914554" width="1920" height="1080" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_320x180_200k" codecs="avc1.64000d" bandwidth="254320" width="320" height="180" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_320x180_400k" codecs="avc1.64000d" bandwidth="507246" width="320" height="180" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_480x270_600k" codecs="avc1.640015" bandwidth="759798" width="480" height="270" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_640x360_1000k" codecs="avc1.64001e" bandwidth="1254758" width="640" height="360" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_640x360_800k" codecs="avc1.64001e" bandwidth="1013310" width="640" height="360" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_768x432_1500k" codecs="avc1.64001e" bandwidth="1883700" width="768" height="432" frameRate="30" sar="1:1" scanType="progressive"/>
+  <Representation id="bbb_30fps_3840x2160_12000k" codecs="avc1.640033" bandwidth="14931538" width="3840" height="2160" frameRate="30" sar="1:1" scanType="progressive"/>
+ </AdaptationSet>
+ <AdaptationSet mimeType="audio/mp4" contentType="audio" subsegmentAlignment="true" subsegmentStartsWithSAP="1">
+  <Accessibility schemeIdUri="urn:tva:metadata:cs:AudioPurposeCS:2007" value="6"/>
+  <Role schemeIdUri="urn:mpeg:dash:role:2011" value="main"/>
+  <SegmentTemplate duration="192512" timescale="48000" media="$RepresentationID$/$RepresentationID$_$Number$.m4a" startNumber="1" initialization="$RepresentationID$/$RepresentationID$_0.m4a"/>
+  <Representation id="bbb_a64k" codecs="mp4a.40.5" bandwidth="67071" audioSamplingRate="48000">
+   <AudioChannelConfiguration schemeIdUri="urn:mpeg:dash:23003:3:audio_channel_configuration:2011" value="2"/>
+  </Representation>
+ </AdaptationSet>
+</Period>
+</MPD>`;

src/dash-parser/handleNode.ts

@@ -0,0 +1,178 @@
+import { ParsedManifest, Attributes } from "./types/parsedManifest";
+import { parseUTCTimingScheme } from "./utils/parseUTCTimingScheme";
+import { Representation } from './types/parsedManifest';
+import { parseAttributes } from './parseAttributes';
+import { constructTemplateUrl } from "./segments/segmentTemplate";
+
+interface HandlerParams {
+  node: Element,
+  parentNode: Element | null,
+  manifest: ParsedManifest,
+  oldAttributes: Attributes,
+  newAttributes: Attributes
+}
+
+export interface HandlerReponse {
+  stopIteration?: boolean,
+  attributes?: Attributes,
+  baseUrl?: string,
+}
+
+interface Handlers {
+  [key: string]: (params: HandlerParams) => HandlerReponse
+}
+
+const handlers: Handlers = {
+  MPD(params: HandlerParams): HandlerReponse {
+    let { node, manifest, oldAttributes, newAttributes } = params;
+
+    // Add attributes at the manifest level.
+    manifest.attributes = newAttributes;
+
+    const response: HandlerReponse = {
+      // do not send these attributes further
+      attributes: {}
+    }
+
+    return response;
+  },
+
+  PERIOD(params: HandlerParams): HandlerReponse {
+    // TODO: handle period
+    let { node, manifest, oldAttributes, newAttributes } = params;
+
+    // somehow clear oldAttributes
+    // manifest.attributes = newAttributes;
+    // newAttributes.tagName = node.tagName;
+    // newAttributes = {};
+
+    // const response: HandlerReponse = {
+    //   // do not send these attributes further
+    //   attributes: {}
+    // }
+
+    // return response;
+  },
+
+  ADAPTIONSET(params: HandlerParams): HandlerReponse {
+    let { node, manifest, oldAttributes, newAttributes } = params;
+
+    // somehow clear oldAttributes
+    // manifest.attributes = newAttributes;
+    // newAttributes.tagName = node.tagName;
+    // newAttributes = {};
+
+    // const response: HandlerReponse = {
+    //   // do not send these attributes further
+    //   attributes: {}
+    // }
+
+    // return response;
+  },
+
+  SEGMENTTEMPLATE(params: HandlerParams): HandlerReponse {
+    let { node, parentNode, manifest, oldAttributes, newAttributes } = params;
+
+    if (parentNode?.tagName === 'REPRESENTATION') {
+      const rep = manifest.representations[manifest.representations.length - 1];
+      if (rep.attributes?.media) {
+        const templateValues = {
+          RepresentationID: rep.attributes.id,
+          Bandwidth: rep.attributes.bandwidth || 0
+        };
+
+        // TODO: generate segments
+        const x = constructTemplateUrl(rep.attributes.media as string, templateValues);
+        rep.attributes.URL = x;
+      }
+    }
+    else {
+      // media and initialization will be set. Ensure we check this in Representation
+    }
+
+    return {};
+  },
+
+  BASEURL(params: HandlerParams): HandlerReponse {
+    // TODO: handle base URL
+
+    // if child, get last representation and update it
+    let { node, manifest, oldAttributes, newAttributes } = params;
+
+    // somehow clear oldAttributes
+    // manifest.attributes = newAttributes;
+    // newAttributes.tagName = node.tagName;
+    // newAttributes = {};
+
+    // const response: HandlerReponse = {
+    //   // do not send these attributes further
+    //   attributes: {}
+    // }
+
+    // return response;
+  },
+
+  REPRESENTATION(params: HandlerParams): HandlerReponse {
+    const { node, manifest, oldAttributes, newAttributes } = params;
+    newAttributes.tagName = node.tagName;
+    console.log(node.tagName);
+    // This means there is a SegmentTemplate.
+    if (oldAttributes.media) {
+      const templateValues = {
+        RepresentationID: oldAttributes.id,
+        Bandwidth: oldAttributes.bandwidth || 0
+      };
+
+      // TODO: generate segments
+
+      const x = constructTemplateUrl(oldAttributes.media as string, templateValues);
+      newAttributes.URL = x;
+    }
+    const rep: Representation = {
+      attributes: {...oldAttributes, ...newAttributes}
+    }
+
+    manifest.representations.push(rep);
+
+    return {};
+  },
+
+  UTCTIMING(params: HandlerParams): HandlerReponse {
+    const { node, manifest } = params;
+    manifest.utcTimingScheme = parseUTCTimingScheme(node);
+
+    const response: HandlerReponse = {
+      // UTCTiming will have no children
+      stopIteration: true,
+    }
+
+    return response;
+  },
+
+  /**
+   * Default handler for an unknown node. Acts as a no-op.
+   */
+   DEFAULT(): HandlerReponse {
+    return {};
+  }
+};
+
+/**
+ * Handles a node while iterating through the tree of XML Nodes from the MPD file.
+ * A function is selected by the name of the node.
+ * Based on the type of node, we store and parse different data.
+ *
+ * @param node The node to parse attributes from
+ */
+ export const handleNode = (
+    node: Element,
+    parentNode: Element | null,
+    manifest: ParsedManifest,
+    oldAttributes: Attributes,
+    newAttributes: Attributes
+  ): HandlerReponse => {
+  const nodeName = node.tagName;
+
+  const handlerFn: (params: HandlerParams) => HandlerReponse = handlers[nodeName] || handlers.DEFAULT;
+  return handlerFn({ node, parentNode, manifest, oldAttributes, newAttributes });
+};

src/dash-parser/parse.ts

@@ -1,19 +1,66 @@
-import { ParsedManifest } from "./types/parsedManifest";
+import { Attributes, ParsedManifest } from "./types/parsedManifest";
 import { testString } from "./examples/mpd";
+import { handleNode } from "./handleNode";
+import { parseAttributes } from "./parseAttributes";
 
 /**
  * Parses a MPD manifest file.
  *
- * @param playlist The URL of the mpd manifest to be parsed.
+ * @param manifest A string containing the XML of a DASH manifest.
  */
-export default function parse(playlist: string): ParsedManifest {
-  const parsedManifest: ParsedManifest = {
-    segments: [],
-    custom: {}
+export default function parse(manifest: string, url: string): ParsedManifest {
+  const initialParsedManifest: ParsedManifest = {
+    uri: url || '',
+    representations: [],
   };
 
-  // TODO: implement parsing.
-  var doc = new DOMParser().parseFromString(testString, 'text/xml');
+  const doc = new DOMParser().parseFromString(manifest, 'text/xml');
 
-  return parsedManifest;
+  return iterateXMLNodes(doc, initialParsedManifest);
+}
+
+// also going to need to keep track of BaseURL
+function iterateXMLNodes(xmlDocument: XMLDocument, manifest: ParsedManifest): ParsedManifest {
+  // TODO: Maybe use some sort of object to check state of the parser
+  // depth, bredth, current period, adaptionset, base URL, ect.
+  // const parserState: ParserState = {
+  //   node: xmlDocument,
+  //   parentNode: null,
+  //   baseURL: '',
+  //   attributes: {}
+  // }
+
+  function iterateNode(node: Node | Element, parentNode: Element | null, attributes?: any, baseUrl?: string): void {
+    // Display node name and attributes
+    // 1 is equivalent to Node.ELEMENT_NODE
+    let newAttributes = {} as Attributes
+    let response;
+
+    if (node.nodeType == 1) {
+      const elementNode = node as Element;
+
+      newAttributes = parseAttributes(elementNode) as Attributes;
+
+      response = handleNode(elementNode, parentNode, manifest, attributes, newAttributes);
+
+      if (response?.attributes) {
+        // Overwrite what attributes should continue to be passed on.
+        newAttributes = response.attributes; 
+      }
+    } else if (node.nodeType === Node.TEXT_NODE) {
+      // Do nothing on text nodes
+    }
+
+    // Recursively iterate child nodes
+    if (!response?.stopIteration) {
+      for (let i = 0; i < node.childNodes.length; i++) {
+        iterateNode(node.childNodes[i], node as Element, {...attributes, ...newAttributes});
+      }
+    }
+  }
+
+  // Start iteration from the root node
+  iterateNode(xmlDocument, null);
+
+  return manifest;
 }