`epoch` should be renamed to its meaning

Checklist

• I’m reporting a feature request
• I’ve verified that I’m running yt-dlp version 2022.01.21. (update instructions)
• I’ve searched the bugtracker for similar issues including closed ones. DO NOT post duplicates
• I’ve read the guidelines for opening an issue

Description

Hello

I have a small suggestion that should improve the understandability of yt-dlp: epoch, the output template field name, states in its name that “it is of the type ‘Unix epoch’”.

This, unfortunately, leads to tedious questions and misunderstandings, because field names should not say what type they are from, but what content, what value they represent. Unfortunately, the help description is also vague, too:

epoch (numeric): Unix epoch when creating the file

I thought that epoch represents the time at which the YouTube Video / Audio file was produced. This is probably wrong: I suspect that the field records the time at which yt-dlp downloads the file.

Proposal: Rename the field epoch to download_timestamp

Because of the help text “epoch (numeric): Unix epoch when creating the file” one could also choose creation_timestamp, but then it is unclear which time is meant: the time when the video was produced? Or the time when the file was downloaded?

Therefore I think that download_timestamp would be the clearest and most useful name instead of epoch.

Thanks a lot, kind regards, Thomas

[pukkandan]

multi_video is not a new thing. Only concating it is. https://github.com/yt-dlp/yt-dlp/blob/fa8fd951184017b9ba164dfa5e6d95d44ff6edd4/yt_dlp/extractor/common.py#L400-L403

[pukkandan]

See the linked commit https://github.com/yt-dlp/yt-dlp/commit/455a15e2dcf29b4712d92a89a95ad5f3ddad69a1#diff-b335630551682c19a781afebcf4d07bf978fb1f8ac04c6bf87428ed5106870f5R1208