youtube-dl 进程间通信实战

从命令行获取视频信息, 输出如下

[Log] -> 执行命令'youtube-dl https://youtu.be/sbz3fOe7rog -F'结果:
[youtube] sbz3fOe7rog: Downloading webpage
[youtube] sbz3fOe7rog: Downloading video info webpage
[info] Available formats for sbz3fOe7rog:
format code  extension  resolution note
249          webm       audio only tiny   59k , opus @ 50k (48000Hz), 1.50MiB
250          webm       audio only tiny   78k , opus @ 70k (48000Hz), 2.00MiB
140          m4a        audio only tiny  129k , m4a_dash container, mp4a.40.2@128k (44100Hz), 3.47MiB
251          webm       audio only tiny  150k , opus @160k (48000Hz), 3.85MiB
278          webm       256x144    144p   95k , webm container, vp9, 15fps, video only, 2.36MiB
160          mp4        256x144    144p  111k , avc1.4d400c, 15fps, video only, 2.95MiB
242          webm       426x240    240p  162k , vp9, 15fps, video only, 2.62MiB
133          mp4        426x240    240p  247k , avc1.4d4015, 15fps, video only, 6.58MiB
18           mp4        512x288    240p  355k , avc1.42001E, mp4a.40.2@ 96k (44100Hz), 9.58MiB (best)

此时 echo -n $? 返回 0

使用正则表达式来匹配, 分组并捕获数据

			val listAudio = ArrayList<Audio>()
			val listVideo = ArrayList<Video>()

			for (a in output.split('\n')) {
				val videoRegex = """^(\d+)\s+(\w+)\s+(\d+x\d+)\s+(\d+)p\s+(\d+)k , (.*), video only, (.+)MiB$""".toRegex()
						var mr = videoRegex.matchEntire(a)
						if (mr != null){
							val (id2, format, scale, frame, rate, info, size) = mr.destructured
							val e = Video(id2.toInt(), format, scale, frame.toInt(), rate.toInt(), info, size.toDouble())
							println(e)
							listVideo.add(e)
							continue
						}

				val audioRegex = """^(\d+)\s+(\w+)\s+audio only tiny\s+(\d+)k , (.*),\s+(.+)MiB$""".toRegex()
						mr = audioRegex.matchEntire(a)
						if (mr != null) {
							val (id2, format, rate, info, size) = mr.destructured
							val e = Audio(id2.toInt(), format, rate.toInt(), info, size.toDouble())
							println(e)
							listAudio.add(e)
							continue
						}

				val videoRegex2 = """^(\d+)\s+(\w+)\s+(\d+x\d+)\s+(\d+)p\s+(\d+)k , (.*), (.+)MiB.+best.+$""".toRegex()
						mr = videoRegex2.matchEntire(a)
						if (mr != null){
							val (id2, format, scale, frame, rate, info, size) = mr.destructured
							val e = Video(id2.toInt(), format, scale, frame.toInt(), rate.toInt(), info, size.toDouble())
							global.log("best video -> $e")
							listVideo.add(e)
							continue
						}
			}

			return mapOf(
				"v" to id,

				"best"  to mapOf(
					"audio" to listAudio.maxBy{ it.rate },
					"video" to listVideo.maxBy{ it.rate }
				),
				
				"available" to mapOf(
					"audios" to listAudio,
					"videos" to listVideo
				)
			)

一个接口就诞生了

{
  "v" : "Ce-4lXZxmvM",
  "best" : {
    "audio" : {
      "id" : 251,
      "format" : "webm",
      "rate" : 164,
      "info" : "opus @160k (48000Hz)",
      "size" : 31.89
    },
    "video" : {
      "id" : 137,
      "format" : "mp4",
      "scale" : "1440x1080",
      "frame" : 1080,
      "rate" : 1643,
      "info" : "avc1.640028, 30fps",
      "size" : 30.17
    }
  },
  "available" : {
    "audios" : [ {
      "id" : 249,
      "format" : "webm",
      "rate" : 73,
      "info" : "opus @ 50k (48000Hz)",
      "size" : 12.1
    }, {
      "id" : 250,
      "format" : "webm",
      "rate" : 93,
      "info" : "opus @ 70k (48000Hz)",
      "size" : 16.1
    }, {
      "id" : 140,
      "format" : "m4a",
      "rate" : 132,
      "info" : "m4a_dash container, mp4a.40.2@128k (44100Hz)",
      "size" : 31.22
    }, {
      "id" : 251,
      "format" : "webm",
      "rate" : 164,
      "info" : "opus @160k (48000Hz)",
      "size" : 31.89
    } ],
    "videos" : [ {
      "id" : 278,
      "format" : "webm",
      "scale" : "192x144",
      "frame" : 144,
      "rate" : 59,
      "info" : "webm container, vp9, 30fps",
      "size" : 6.39
    }, {
      "id" : 160,
      "format" : "mp4",
      "scale" : "192x144",
      "frame" : 144,
      "rate" : 84,
      "info" : "avc1.4d400c, 30fps",
      "size" : 2.87
    }, {
      "id" : 242,
      "format" : "webm",
      "scale" : "320x240",
      "frame" : 240,
      "rate" : 117,
      "info" : "vp9, 30fps",
      "size" : 10.15
    }, {
      "id" : 133,
      "format" : "mp4",
      "scale" : "320x240",
      "frame" : 240,
      "rate" : 175,
      "info" : "avc1.4d400d, 30fps",
      "size" : 4.22
    }, {
      "id" : 243,
      "format" : "webm",
      "scale" : "480x360",
      "frame" : 360,
      "rate" : 226,
      "info" : "vp9, 30fps",
      "size" : 16.66
    }, {
      "id" : 244,
      "format" : "webm",
      "scale" : "640x480",
      "frame" : 480,
      "rate" : 378,
      "info" : "vp9, 30fps",
      "size" : 25.6
    }, {
      "id" : 134,
      "format" : "mp4",
      "scale" : "480x360",
      "frame" : 360,
      "rate" : 416,
      "info" : "avc1.4d401e, 30fps",
      "size" : 7.99
    }, {
      "id" : 247,
      "format" : "webm",
      "scale" : "960x720",
      "frame" : 720,
      "rate" : 641,
      "info" : "vp9, 30fps",
      "size" : 42.0
    }, {
      "id" : 135,
      "format" : "mp4",
      "scale" : "640x480",
      "frame" : 480,
      "rate" : 728,
      "info" : "avc1.4d401e, 30fps",
      "size" : 13.01
    }, {
      "id" : 248,
      "format" : "webm",
      "scale" : "1440x1080",
      "frame" : 1080,
      "rate" : 1039,
      "info" : "vp9, 30fps",
      "size" : 69.33
    }, {
      "id" : 136,
      "format" : "mp4",
      "scale" : "960x720",
      "frame" : 720,
      "rate" : 1129,
      "info" : "avc1.4d401f, 30fps",
      "size" : 20.92
    }, {
      "id" : 137,
      "format" : "mp4",
      "scale" : "1440x1080",
      "frame" : 1080,
      "rate" : 1643,
      "info" : "avc1.640028, 30fps",
      "size" : 30.17
    }, {
      "id" : 18,
      "format" : "mp4",
      "scale" : "480x360",
      "frame" : 360,
      "rate" : 275,
      "info" : "avc1.42001E, mp4a.40.2@ 96k (44100Hz)",
      "size" : 66.41
    } ]
  }
}

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