ytcheck.lua

#!/usr/bin/lua

local _FEEDS = {
    "https://www.youtube.com/feeds/videos.xml?channel_id=UCzQUP1qoWDoEbmsQxvdjxgQ", -- JRE
    "https://www.youtube.com/feeds/videos.xml?channel_id=UCNAxrHudMfdzNi6NxruKPLw", -- Sam
}

local sh = require("sh")
local _t = tostring
local feedparser = require("feedparser")
local lfs = require("lfs")
local fd = sh.command("fd")
local ytdl = sh.command("youtube-dl")
local dkjson = require("dkjson")
local logger = sh.command("logger")

local podcastFolder = os.getenv("PODCAST_FOLDER")
if type(podcastFolder) ~= "string" or #podcastFolder == 0 then
    logger("-t ytcheck", "'Set PODCAST_FOLDER env var plz folk nub.'")
    os.exit(1)
end
if podcastFolder:find("\\") then
    logger("-t ytcheck", "'folk you idiot, you put \\ in the path again.'")
    os.exit(1)
end
if podcastFolder:sub(#podcastFolder) ~= "/" then podcastFolder = podcastFolder .. "/" end

local podcastFolderExists = lfs.attributes(podcastFolder, "mode")
if not podcastFolderExists then
    logger("-t ytcheck", "'dafuq PODCAST_FOLDER'")
    os.exit(1)
end

lfs.chdir(podcastFolder)

for _, feed in next, _FEEDS do
    local rawFeed = _t(sh.command("curl")("-s", feed))
    if rawFeed and type(rawFeed) == "string" and rawFeed ~= "" then
        local parsed = feedparser.parse(rawFeed)
        if type(parsed) == "table" and parsed.feed then

            local name = parsed.feed.title:gsub("[%/%?%<%>%\\%:%*%|%q%.%c]", "")
            name = name:gsub("%s+$", "")

            -- Check that the output folder exists
            local fullPath = podcastFolder .. name
            lfs.mkdir(fullPath) -- No problem just doing it every time
            lfs.chdir(fullPath)

            local toDownload = {}

            -- Find for any missing videos
            local vidyas = parsed.entries
            for _, vidya in next, vidyas do
                local id = vidya.id and vidya.id:match("^yt:video:([%w%_%-]+)$")
                if id then
                    local found = _t(fd(id))
                    if found and found == "" then
                        local json = dkjson.decode(_t(ytdl("-j", vidya.link)))
                        if json and not json.is_live then
                            toDownload[#toDownload+1] = id
                        end
                    end
                end
            end

            logger("-t ytcheck", "'" .. #toDownload .. " downloads queued for " .. name .. "'")

            -- Fetch!
            for _, fetch in next, toDownload do
                logger("-t ytcheck", "'Downloading audio from YT #" .. fetch .. "'")
                ytdl(
                    "--no-playlist",
                    "--retries 1",
                    "--abort-on-unavailable-fragment",
                    "--no-overwrites",
                    "--no-progress",
                    "--extract-audio",
                    fetch
                )
            end
        end
    end
end