Adding missing manifest information on to segments (EXT-X-PROGRAM-DATE-TIME)

[rart]

Description

The segment metadata is currently missing the information that comes from the EXT-X-PROGRAM-DATE-TIME.

Specific Changes proposed

I've added the dateTimeObject & dateTimeString to the segment data object. The information as already coming through from the buffer, only missing to be added to the segment data object that's published.

Requirements Checklist

• Feature implemented / Bug fixed
• If necessary, more likely in a feature request than a bug fix
  • Unit Tests updated or fixed
  • Docs/guides updated
  • Example created (starter template on JSBin)
• Reviewed by Two Core Contributors

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[gkatsev]

this should probably default to the empty string.

[rart]

Didn't seem accurate to me. I felt null was a better representation of the value not being there (e.g. manifest doesn't have that information). I can change if '' is preferred, though.

[gkatsev]

I think it should either be a string to match the type of that property when a value is present, or, maybe better yet, not have the property at all if a value is absent.

[rart]

I disagree; but ok :) I'll make the update.

[gkatsev]

Why do you think having null values would be better?

[rart]

I like the consistency in the segment object plus think it could avoid issues of developer not checking if the property is there and getting a error like "cannot read property getTime of undefined" — trying to do dateTimeObject.getTime — for example not knowing that the prop won't be there sometimes. Ultimately, one way or another devs will need to check but just it felt more reliable to be that way.

Not sure if all of the other props there will always be in manifests but according to the code, the other properties are not skipped if not in.

[gkatsev]

If a property is missing, it'll still be the same null-check:

if (cue.dataTimeObject) {
}
if (cue.dateTimeString) {
}

Also, I only was saying that the dateTimeString should have defaulted to an empty string (which is a falsey value) and not the dateTimeObject

[rart]

so you're ok with dateTimeObject being null? You just want dateTimeString to be ''?

or are we sticking with removing them all together when not present?

[rart]

@gkatsev where do we stand on this adjustment?

[forbesjo]

@rart I believe what you have is fine, if the program date time tag has no value for some reason (not sure if this is allowed in the HLS spec) I don't think we should have the property be present with an empty string but rather use null.

[welcome]

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