Add -o option for redirecting output

src/invidious.cr

@@ -16,6 +16,7 @@
 
 require "detect_language"
 require "digest/md5"
+require "file_utils"
 require "kemal"
 require "openssl/hmac"
 require "option_parser"
@@ -35,6 +36,8 @@ channel_threads = CONFIG.channel_threads
 feed_threads = CONFIG.feed_threads
 video_threads = CONFIG.video_threads
 
+logger = Invidious::LogHandler.new
+
 Kemal.config.extra_options do |parser|
   parser.banner = "Usage: invidious [arguments]"
   parser.on("-t THREADS", "--crawl-threads=THREADS", "Number of threads for crawling YouTube (default: #{crawl_threads})") do |number|
@@ -69,6 +72,10 @@ Kemal.config.extra_options do |parser|
       exit
     end
   end
+  parser.on("-o OUTPUT", "--output=OUTPUT", "Redirect output (default: STDOUT)") do |output|
+    FileUtils.mkdir_p(File.dirname(output))
+    logger = Invidious::LogHandler.new(File.open(output, mode: "a"))
+  end
 end
 
 Kemal::CLI.new
@@ -295,7 +302,7 @@ get "/watch" do |env|
     next env.redirect "/watch?v=#{ex.message}"
   rescue ex
     error_message = ex.message
-    STDOUT << id << " : " << ex.message << "\n"
+    logger.write("#{id} : #{ex.message}\n")
     next templated "error"
   end
 
@@ -3849,4 +3856,5 @@ add_handler FilteredCompressHandler.new
 add_handler DenyFrame.new
 add_context_storage_type(User)
 
+Kemal.config.logger = logger
 Kemal.run