Fix order of REGEX_METHOD pattern

[TakuSemba]

I'm trying to play a content of HLS + WideVine + cenc , and I found that the content is not playing properly on pre-Nougat devices.

HLS + WideVine + cenc should be playable according to this

After I debugging the code, it seems like ExoPlayer judges the content cbcs mode, even if the content is cenc mode at this point.

Shouldn't METHOD_SAMPLE_AES be put after METHOD_SAMPLE_AES_CENC , METHOD_SAMPLE_AES_CTR ??, otherwise METHOD_SAMPLE_AES_CENC, METHOD_SAMPLE_AES_CTR would never match.

#EXTM3U
#EXT-X-VERSION:6
## Generated with https://github.com/google/shaka-packager version 2453c93f91-release
#EXT-X-TARGETDURATION:12
#EXT-X-PLAYLIST-TYPE:VOD
#EXT-X-MAP:URI="init.mp4"
#EXTINF:10.000,
1.m4s
#EXT-X-DISCONTINUITY
#EXT-X-KEY:METHOD=SAMPLE-AES-CTR,URI="data:text/plain;base64,AAAAN3Bzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAABciD3Rlc3QgY29udGVudCBpZEjj3JWbBg==",KEYID=0x6D76F25CB17F5E16B8EAEF6BBF582D8E,KEYFORMATVERSIONS="1",KEYFORMAT="urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed"
#EXTINF:10.792,
2.m4s
#EXTINF:9.792,
3.m4s
#EXTINF:10.000,

  private static final String METHOD_NONE = "NONE";
  private static final String METHOD_AES_128 = "AES-128";
  private static final String METHOD_SAMPLE_AES = "SAMPLE-AES";
  // Replaced by METHOD_SAMPLE_AES_CTR. Keep for backward compatibility.
  private static final String METHOD_SAMPLE_AES_CENC = "SAMPLE-AES-CENC";
  private static final String METHOD_SAMPLE_AES_CTR = "SAMPLE-AES-CTR";
  private static final Pattern REGEX_METHOD =
      Pattern.compile(
          "METHOD=("
              + METHOD_NONE
              + "|"
              + METHOD_AES_128
              + "|"
              + METHOD_SAMPLE_AES
              + "|"
              + METHOD_SAMPLE_AES_CENC
              + "|"
              + METHOD_SAMPLE_AES_CTR
              + ")");
Matcher matcher = REGEX_METHOD.matcher("#EXT-X-KEY:METHOD=SAMPLE-AES-CTR,URI=\"data:text/plain;base64,AAAAN3Bzc2gAAAAA7e+LqXnWSs6jyCfc1R0h7QAAABciD3Rlc3QgY29udGVudCBpZEjj3JWbBg==\",KEYID=0x6D76F25CB17F5E16B8EAEF6BBF582D8E,KEYFORMATVERSIONS=\"1\",KEYFORMAT=\"urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed\"");
matcher.find() ? matcher.group(1) : null;
// ↑ this returns "SAMPLE-AES" because SAMPLE-AES is before METHOD_SAMPLE_AES_CTR

[AquilesCanta]

Hi, thanks for diagnosing and reporting! This is indeed a bug and we will fix it. But it's probably better not to depend on the method ordering. We will soon push a fix along with tests for it. A commit reference will appear here.

[TakuSemba]

We will soon push a fix along with tests for it. A commit reference will appear here.

thanks, does it mean my commit will be merged with your changes?

[ojw28]

Closing as a different fixed has now been merged. Thanks!