Added support for stream titles/custom date format in filename

[11ib]

I've added the -d and -t flags for inserting a custom date format (using the Bash Date Format) and grabbing the title of a stream when recording a stream.

[Hakkin]

Thanks for the pull request! This looks good, but a few things need fixing.

Mostly small changes needed, but sanitizing filenames is a big one. I'm not quite sure what the best way to do this in bash is, the simplest way would probably be to nuke all non-alphanumeric characters in the filename, but that also might be slightly overkill.

[Hakkin]

Suggested change

	while getopts "d:pht" opt
	while getopts ":phtd:" opt

This should be ":phtd:", ":" at the start of a getopt argument prevents it from displaying debug errors.

[Hakkin]

The new switches should be added to the usage text.

[Hakkin]

We need to sanitize the filename somehow, as it is, if a streamer has their title set to ../title, the file will be created up a directory. We also have to consider special characters that are not allowed in filenames, both on Windows and Linux.

[Hakkin]

Suggested change

	filename+=$(date -u '+%Y-%m-%d-%H-%M-%S-(%Z)')
	filename+=$(date -u '+%Y_%m_%d_%H_%M_%S_(%Z)')

I would also prefer the date format stay the same as it was before, +%Y_%m_%d_%H_%M_%S_(%Z)

[camjac251]

I've seen another go project deal with filenames by converting it to utf-8
It might be useful here
https://github.com/uhthomas/kipp/blob/e8189beaa3e4ae20366890cfb45e0f57bf86678b/server.go#L132

[camjac251]

Having the filename include the title of the stream might not be ideal for archiving. A lot of times, a streamer will set their title after going live so you'd have some duplicates. I've opened an issue with a feature request for a logging format and think logging the titles separately could be better than filenames. #12

[Hakkin]

Hi @11ib, would you mind checking to see if the new record.sh -f option in the master branch does what you want?
You can define any program to run when the stream starts, the output of that program (standard output) will be used as the output filename.
You can use the variables $username and $id in the command and they will be expanded and passed to the script.
To avoid your shell trying to expand the variables itself, you should make sure to put the -f argument in single quotes (') and not double quotes (").
If you want some examples to test, I've tried these and confirmed they're working:

./record.sh -f 'until youtube-dl --get-filename -o "%(uploader)s (%(uploader_id)s) - %(upload_date)s (%(timestamp)d) - %(id)s - %(description)s" "https://twitch.tv/${username}"; do continue; done' username1 username2

this is using a bash until loop to call youtube-dl and request a formatted filename, it will usually give a few "stream is offline" errors until it works.
This will get you a filename formatted like displayName (username) - 20201202 (1606896000) - 40000000000 - This is a title.ts
You can use whatever youtube-dl template options you want.

You can also of course write custom bash scripts to fetch whatever info you want, or any other commands for that matter, I wrote a simple bash script that does similar to the above without using youtube-dl.

#!/bin/bash

id="${1}"
json="$(curl --silent --fail -H "Accept: application/vnd.twitchtv.v5+json" -H "Client-ID: jzkbprff40iqj646a697cyrvl0zt2m6" "https://api.twitch.tv/kraken/streams/${id}")"
stream="$(jq .stream <<< "${json}")"
if [ "${stream}" == "null" ]
then
	sleep 1
	exit 1
fi

display_name="$(jq -r .channel.display_name <<< "${stream}")"
user_id="$(jq -r .channel._id <<< "${stream}")"
created_at="$(jq -r .created_at <<< "${stream}")"
broadcast_id="$(jq -r ._id <<< "${stream}")"
status="$(jq -r .channel.status <<< "${stream}")"

printf "%s - %s (%d) - %s (%d)" "$(date -u -d "${created_at}" "+%Y%m%d%H%M%S")" "${display_name}" "${user_id}" "${status}" "${broadcast_id}"

put this in a file called filename.sh and chmod +x it, then it can be used like so:
./record.sh -f 'until ./filename.sh "${id}"; do continue; done' username1 username2
it will output to a filename like this:
20201202000000 - displayName (userID) - This is a title (broadcastID).ts