invidious-experimenting/src/helpers.cr
2018-03-14 18:06:21 -05:00

408 lines
10 KiB
Crystal

macro add_mapping(mapping)
def initialize({{*mapping.keys.map { |id| "@#{id}".id }}})
end
def to_a
return [{{*mapping.keys.map { |id| "@#{id}".id }}}]
end
DB.mapping({{mapping}})
end
macro templated(filename)
render "src/views/#{{{filename}}}.ecr", "src/views/layout.ecr"
end
class Config
YAML.mapping({
pool_size: Int32,
threads: Int32,
db: NamedTuple(
user: String,
password: String,
host: String,
port: Int32,
dbname: String,
),
redirect: Bool,
})
end
class Video
module HTTPParamConverter
def self.from_rs(rs)
HTTP::Params.parse(rs.read(String))
end
end
add_mapping({
id: String,
info: {
type: HTTP::Params,
default: HTTP::Params.parse(""),
converter: Video::HTTPParamConverter,
},
updated: Time,
title: String,
views: Int64,
likes: Int32,
dislikes: Int32,
wilson_score: Float64,
published: Time,
description: String,
})
end
class RedditSubmit
JSON.mapping({
data: RedditSubmitData,
})
end
class RedditSubmitData
JSON.mapping({
children: Array(RedditThread),
})
end
class RedditThread
JSON.mapping({
data: RedditThreadData,
})
end
class RedditThreadData
JSON.mapping({
subreddit: String,
id: String,
num_comments: Int32,
score: Int32,
author: String,
permalink: String,
title: String,
})
end
# See http://www.evanmiller.org/how-not-to-sort-by-average-rating.html
def ci_lower_bound(pos, n)
if n == 0
return 0.0
end
# z value here represents a confidence level of 0.95
z = 1.96
phat = 1.0*pos/n
return (phat + z*z/(2*n) - z * Math.sqrt((phat*(1 - phat) + z*z/(4*n))/n))/(1 + z*z/n)
end
def elapsed_text(elapsed)
millis = elapsed.total_milliseconds
return "#{millis.round(2)}ms" if millis >= 1
"#{(millis * 1000).round(2)}µs"
end
def get_client(pool)
while pool.empty?
sleep rand(0..10).milliseconds
end
return pool.shift
end
def fetch_video(id, client)
info = client.get("/get_video_info?video_id=#{id}&el=detailpage&ps=default&eurl=&gl=US&hl=en").body
html = client.get("/watch?v=#{id}&bpctr=#{Time.new.epoch + 2000}").body
html = XML.parse_html(html)
info = HTTP::Params.parse(info)
if info["reason"]?
info = client.get("/get_video_info?video_id=#{id}&ps=default&eurl=&gl=US&hl=en").body
info = HTTP::Params.parse(info)
if info["reason"]?
raise info["reason"]
end
end
title = info["title"]
views = info["view_count"].to_i64
likes = html.xpath_node(%q(//button[@title="I like this"]/span))
likes = likes.try &.content.delete(",").try &.to_i
likes ||= 0
dislikes = html.xpath_node(%q(//button[@title="I dislike this"]/span))
dislikes = dislikes.try &.content.delete(",").try &.to_i
dislikes ||= 0
description = html.xpath_node(%q(//p[@id="eow-description"]))
description = description ? description.to_xml : ""
wilson_score = ci_lower_bound(likes, likes + dislikes)
published = html.xpath_node(%q(//strong[contains(@class,"watch-time-text")]))
if published
published = published.content
else
raise "Could not find date published"
end
published = published.lchop("Published ")
published = published.lchop("Streamed live ")
published = published.lchop("Started streaming ")
published = published.lchop("on ")
published = published.lchop("Scheduled for ")
if !published.includes?("ago")
published = Time.parse(published, "%b %-d, %Y")
else
# Time matches format "20 hours ago", "40 minutes ago"...
delta = published.split(" ")[0].to_i
case published
when .includes? "minute"
published = Time.now - delta.minutes
when .includes? "hour"
published = Time.now - delta.hours
else
raise "Could not parse #{published}"
end
end
video = Video.new(id, info, Time.now, title, views, likes, dislikes, wilson_score, published, description)
return video
end
def get_video(id, client, db, refresh = true)
if db.query_one?("SELECT EXISTS (SELECT true FROM videos WHERE id = $1)", id, as: Bool)
video = db.query_one("SELECT * FROM videos WHERE id = $1", id, as: Video)
# If record was last updated over an hour ago, refresh (expire param in response lasts for 6 hours)
if refresh && Time.now - video.updated > 1.hours
video = fetch_video(id, client)
db.exec("DELETE FROM videos * WHERE id = $1", id)
args = arg_array(video.to_a)
db.exec("INSERT INTO videos VALUES (#{args})", video.to_a)
end
else
video = fetch_video(id, client)
args = arg_array(video.to_a)
db.exec("INSERT INTO videos VALUES (#{args})", video.to_a)
end
return video
end
def search(query, client)
html = client.get("https://www.youtube.com/results?q=#{query}&sp=EgIQAVAU").body
html = XML.parse_html(html)
html.xpath_nodes(%q(//ol[@class="item-section"]/li)).each do |item|
root = item.xpath_node(%q(div[contains(@class,"yt-lockup-video")]/div))
if root
link = root.xpath_node(%q(div[contains(@class,"yt-lockup-thumbnail")]/a/@href))
if link
yield link.content.split("=")[1]
end
end
end
end
def splice(a, b)
c = a[0]
a[0] = a[b % a.size]
a[b % a.size] = c
return a
end
def decrypt_signature(a)
a = a.split("")
a.reverse!
a.delete_at(0)
a.reverse!
a = splice(a, 50)
return a.join("")
end
def rank_videos(db, n)
top = [] of {Float64, String}
db.query("SELECT id, wilson_score, published FROM videos WHERE views > 5000 ORDER BY published DESC LIMIT 10000") do |rs|
rs.each do
id = rs.read(String)
wilson_score = rs.read(Float64)
published = rs.read(Time)
# Exponential decay, older videos tend to rank lower
temperature = wilson_score * Math.exp(-0.000005*((Time.now - published).total_minutes))
top << {temperature, id}
end
end
top.sort!
# Make hottest come first
top.reverse!
top = top.map { |a, b| b }
# Return top
return top[0..n - 1]
end
def make_client(url)
context = OpenSSL::SSL::Context::Client.new
context.add_options(
OpenSSL::SSL::Options::ALL |
OpenSSL::SSL::Options::NO_SSL_V2 |
OpenSSL::SSL::Options::NO_SSL_V3
)
client = HTTP::Client.new(url, context)
client.read_timeout = 10.seconds
client.connect_timeout = 10.seconds
return client
end
def get_reddit_comments(id, client, headers)
query = "(url:3D#{id}%20OR%20url:#{id})%20(site:youtube.com%20OR%20site:youtu.be)"
search_results = client.get("/search.json?q=#{query}", headers)
if search_results.status_code == 200
search_results = RedditSubmit.from_json(search_results.body)
thread = search_results.data.children.sort_by { |child| child.data.score }[-1]
result = client.get("/r/#{thread.data.subreddit}/comments/#{thread.data.id}?limit=100&sort=top", headers).body
result = JSON.parse(result)
elsif search_results.status_code == 302
search_results = client.get(search_results.headers["Location"], headers).body
result = JSON.parse(search_results)
thread = RedditThread.from_json(result[0]["data"]["children"][0].to_json)
else
raise "Got error code #{search_results.status_code}"
end
comments = result[1]["data"]["children"]
return comments, thread
end
def template_comments(root)
html = ""
root.each do |child|
if child["data"]["body_html"]?
author = child["data"]["author"]
score = child["data"]["score"]
body_html = HTML.unescape(child["data"]["body_html"].as_s)
# Replace local links wtih links back to Reddit
body_html = fill_links(body_html, "https", "www.reddit.com")
replies_html = ""
if child["data"]["replies"] != ""
replies_html = template_comments(child["data"]["replies"]["data"]["children"])
end
content = <<-END_HTML
<p>
<a href="javascript:void(0)" onclick="toggle(this)">[ - ]</a> #{score} <b>#{author}</b>
</p>
<div>
#{body_html}
#{replies_html}
</div>
END_HTML
if child["data"]["depth"].as_i > 0
html += <<-END_HTML
<div class="pure-g">
<div class="pure-u-1-24"></div>
<div class="pure-u-23-24">
#{content}
</div>
</div>
END_HTML
else
html += <<-END_HTML
<div class="pure-g">
<div class="pure-u-1">
#{content}
</div>
</div>
END_HTML
end
end
end
return html
end
def number_with_separator(number)
number.to_s.reverse.gsub(/(\d{3})(?=\d)/, "\\1,").reverse
end
def arg_array(array)
args = [] of String
(1..array.size).each { |i| args << "($#{i})," }
args = args.join("")
args = args.chomp(",")
return args
end
def add_alt_links(html)
alt_links = [] of {Int32, String}
# This is painful but is likely the only way to accomplish this in Crystal,
# as Crystigiri and others are not able to insert XML Nodes into a document.
# The goal here is to use as little regex as possible
html.scan(/<a[^>]*>([^<]+)<\/a>/) do |match|
anchor = XML.parse_html(match[0])
anchor = anchor.xpath_node("//a").not_nil!
url = URI.parse(HTML.unescape(anchor["href"]))
if ["www.youtube.com", "m.youtube.com"].includes?(url.host) && url.path == "/watch"
alt_link = <<-END_HTML
<a href="#{url.full_path}">
<i class="fa fa-link" aria-hidden="true"></i>
</a>
END_HTML
elsif url.host == "youtu.be"
alt_link = <<-END_HTML
<a href="/watch?v=#{url.full_path.lchop("/")}">
<i class="fa fa-link" aria-hidden="true"></i>
</a>
END_HTML
else
alt_link = ""
end
alt_links << {match.end.not_nil!, alt_link}
end
alt_links.reverse!
alt_links.each do |position, alt_link|
html = html.insert(position, alt_link)
end
return html
end
def fill_links(html, scheme, host)
html = XML.parse_html(html)
html.xpath_nodes("//a").each do |match|
url = URI.parse(match["href"])
if !url.host # If reddit link
url.scheme = scheme
url.host = host
match["href"] = url
end
end
html = html.to_xml
end