Player crashes when no text plugins but content has closed captions

[tykus160]

Have you read the FAQ and checked for duplicate open issues?
Yes

What version of Shaka Player are you using?
3.3.10

Can you reproduce the issue with our latest release version?
Yes

Can you reproduce the issue with the latest code from main?
Yes

Are you using the demo app or your own custom app?
Custom

If custom app, can you reproduce the issue using our demo app?
No

What browser and OS are you using?
MacOS Chrome

For embedded devices (smart TVs, etc.), what model and firmware version are you using?

What are the manifest and license server URIs?

https://livesim.dashif.org/dash/vod/testpic_2s/cea608.mpd

What configuration are you using? What is the output of player.getConfiguration()?

{
    "drm": {
        "retryParameters": {
            "maxAttempts": 2,
            "baseDelay": 1000,
            "backoffFactor": 2,
            "fuzzFactor": 0.5,
            "timeout": 30000,
            "stallTimeout": 5000,
            "connectionTimeout": 10000,
            "suppressNetworkTimeoutWarnings": false
        },
        "servers": {},
        "clearKeys": {},
        "advanced": {},
        "preserveMediaKeySessions": false,
        "delayLicenseRequestUntilPlayed": false,
        "logLicenseExchange": false,
        "updateExpirationTime": 1,
        "preferredKeySystems": []
    },
    "manifest": {
        "retryParameters": {
            "maxAttempts": 2,
            "baseDelay": 1000,
            "backoffFactor": 2,
            "fuzzFactor": 0.5,
            "timeout": 30000,
            "stallTimeout": 5000,
            "connectionTimeout": 10000,
            "suppressNetworkTimeoutWarnings": false
        },
        "availabilityWindowOverride": null,
        "disableAudio": false,
        "disableVideo": false,
        "disableText": false,
        "disableThumbnails": false,
        "defaultPresentationDelay": 0,
        "overrideDolbyVisionCodecs": false,
        "dash": {
            "clockSyncUri": "",
            "ignoreDrmInfo": false,
            "disableXlinkProcessing": false,
            "xlinkFailGracefully": false,
            "ignoreMinBufferTime": false,
            "autoCorrectDrift": true,
            "initialSegmentLimit": 1000,
            "ignoreSuggestedPresentationDelay": false,
            "ignoreEmptyAdaptationSet": false,
            "ignoreMaxSegmentDuration": false,
            "keySystemsByURI": {
                "urn:uuid:1077efec-c0b2-4d02-ace3-3c1e52e2fb4b": "org.w3.clearkey",
                "urn:uuid:edef8ba9-79d6-4ace-a3c8-27dcd51d21ed": "com.widevine.alpha",
                "urn:uuid:9a04f079-9840-4286-ab92-e65be0885f95": "com.microsoft.playready",
                "urn:uuid:79f0049a-4098-8642-ab92-e65be0885f95": "com.microsoft.playready",
                "urn:uuid:f239e769-efa3-4850-9c16-a903c6932efb": "com.adobe.primetime"
            },
            "minimumUpdatePeriodOverride": null,
            "suggestedPresentationDelayOverride": null
        },
        "hls": {
            "ignoreTextStreamFailures": false,
            "ignoreImageStreamFailures": false,
            "useFullSegmentsForStartTime": false,
            "defaultAudioCodec": "mp4a.40.2",
            "defaultVideoCodec": "avc1.42E01E"
        }
    },
    "streaming": {
        "retryParameters": {
            "maxAttempts": 2,
            "baseDelay": 1000,
            "backoffFactor": 2,
            "fuzzFactor": 0.5,
            "timeout": 30000,
            "stallTimeout": 5000,
            "connectionTimeout": 10000,
            "suppressNetworkTimeoutWarnings": false
        },
        "rebufferingGoal": 2,
        "bufferingGoal": 10,
        "bufferBehind": 30,
        "ignoreTextStreamFailures": false,
        "alwaysStreamText": false,
        "startAtSegmentBoundary": false,
        "gapDetectionThreshold": 0.1,
        "smallGapLimit": 0.5,
        "jumpLargeGaps": false,
        "durationBackoff": 1,
        "forceTransmuxTS": false,
        "safeSeekOffset": 5,
        "stallEnabled": true,
        "stallThreshold": 1,
        "stallSkip": 0.1,
        "useNativeHlsOnSafari": true,
        "parsePrftBox": false,
        "inaccurateManifestTolerance": 2,
        "lowLatencyMode": false,
        "autoLowLatencyMode": false,
        "forceHTTPS": false,
        "preferNativeHls": false,
        "updateIntervalSeconds": 1,
        "dispatchAllEmsgBoxes": false,
        "observeQualityChanges": false,
        "enableSegmentStartWorkaround": false
    },
    "offline": {
        "usePersistentLicense": true
    },
    "abr": {
        "enabled": true,
        "useNetworkInformation": true,
        "defaultBandwidthEstimate": 1000000,
        "switchInterval": 8,
        "bandwidthUpgradeTarget": 0.85,
        "bandwidthDowngradeTarget": 0.95,
        "forceLowestRateOnTimeout": false,
        "restrictions": {
            "minWidth": 0,
            "maxWidth": null,
            "minHeight": 0,
            "maxHeight": null,
            "minPixels": 0,
            "maxPixels": null,
            "minFrameRate": 0,
            "maxFrameRate": null,
            "minBandwidth": 0,
            "maxBandwidth": null
        },
        "advanced": {
            "minTotalBytes": 128000,
            "minBytes": 16000,
            "fastHalfLife": 2,
            "slowHalfLife": 5
        }
    },
    "preferredAudioLanguage": "",
    "preferredTextLanguage": "",
    "preferredVariantRole": "",
    "preferredTextRole": "",
    "forceInitialTextLanguage": false,
    "preferredAudioChannelCount": 2,
    "preferredVideoCodecs": [],
    "preferredAudioCodecs": [],
    "preferForcedSubs": false,
    "preferredDecodingAttributes": [],
    "restrictions": {
        "minWidth": 0,
        "maxWidth": null,
        "minHeight": 0,
        "maxHeight": null,
        "minPixels": 0,
        "maxPixels": null,
        "minFrameRate": 0,
        "maxFrameRate": null,
        "minBandwidth": 0,
        "maxBandwidth": null
    },
    "playRangeStart": 0,
    "playRangeEnd": null,
    "cmcd": {
        "enabled": false,
        "sessionId": "",
        "contentId": "",
        "useHeaders": false
    }
}

What did you do?

Prepared custom build without text plugins (python3 build/build.py --name wt-test +@complete -@text)
Tried to play content with closed captions.

What did you expect to happen?
Player starts to play, closed caption tracks are selectable.

What actually happened?

Player crashed due to following error on 3.3.10:

TypeError: Cannot read properties of undefined (reading 'prototype')

On current main, error is following:

TypeError: a is not a function
    at shaka.text.TextEngine.initParser

The problem is related to the fact, that if text engine needs to be initiated due to closed captions, MediaSourceEngine inits it with text/vtt MIME type. TextEngine fails with assertion that no factory has been found for given MIME type.

It should be easily fixed with changing used MIME type in MediaSourceEngine to CEA608 or 708.

Bonus question - as there is a possibility to create custom build without certain plugins, do assertions in TextEngine around finding factory are valid? Shouldn't shaka instead throw an error but continue to play without subtitles? Or maybe prepare some dummy text parser that's always included in core?

[avelad]

PR that will resolve it #5160 :)

[avelad]

Fixed with 6937325