Automatically migrate database

2025-12-16 09:58:50 +00:00 · 2019-04-10 16:23:37 -05:00
parent b8c87632e6
commit 5dc45c35e6
5 changed files with 123 additions and 9 deletions
--- a/src/invidious/helpers/signatures.cr
+++ b/src/invidious/helpers/signatures.cr
@@ -0,0 +1,70 @@
+def fetch_decrypt_function(id = "CvFH_6DNRCY")
+  client = make_client(YT_URL)
+  document = client.get("/watch?v=#{id}&gl=US&hl=en&disable_polymer=1").body
+  url = document.match(/src="(?<url>\/yts\/jsbin\/player_ias-.{9}\/en_US\/base.js)"/).not_nil!["url"]
+  player = client.get(url).body
+
+  function_name = player.match(/^(?<name>[^=]+)=function\(a\){a=a\.split\(""\)/m).not_nil!["name"]
+  function_body = player.match(/^#{Regex.escape(function_name)}=function\(a\){(?<body>[^}]+)}/m).not_nil!["body"]
+  function_body = function_body.split(";")[1..-2]
+
+  var_name = function_body[0][0, 2]
+  var_body = player.delete("\n").match(/var #{Regex.escape(var_name)}={(?<body>(.*?))};/).not_nil!["body"]
+
+  operations = {} of String => String
+  var_body.split("},").each do |operation|
+    op_name = operation.match(/^[^:]+/).not_nil![0]
+    op_body = operation.match(/\{[^}]+/).not_nil![0]
+
+    case op_body
+    when "{a.reverse()"
+      operations[op_name] = "a"
+    when "{a.splice(0,b)"
+      operations[op_name] = "b"
+    else
+      operations[op_name] = "c"
+    end
+  end
+
+  decrypt_function = [] of {name: String, value: Int32}
+  function_body.each do |function|
+    function = function.lchop(var_name).delete("[].")
+
+    op_name = function.match(/[^\(]+/).not_nil![0]
+    value = function.match(/\(a,(?<value>[\d]+)\)/).not_nil!["value"].to_i
+
+    decrypt_function << {name: operations[op_name], value: value}
+  end
+
+  return decrypt_function
+end
+
+def decrypt_signature(fmt, code)
+  if !fmt["s"]?
+    return ""
+  end
+
+  a = fmt["s"]
+  a = a.split("")
+
+  code.each do |item|
+    case item[:name]
+    when "a"
+      a.reverse!
+    when "b"
+      a.delete_at(0..(item[:value] - 1))
+    when "c"
+      a = splice(a, item[:value])
+    end
+  end
+
+  signature = a.join("")
+  return "&#{fmt["sp"]?}=#{signature}"
+end
+
+def splice(a, b)
+  c = a[0]
+  a[0] = a[b % a.size]
+  a[b % a.size] = c
+  return a
+end