Logger: Add color support for different log levels

src/invidious/helpers/logger.cr

@@ -1,3 +1,5 @@
+require "colorize"
+
 enum LogLevel
   All   = 0
   Trace = 1
@@ -10,7 +12,7 @@ enum LogLevel
 end
 
 class Invidious::LogHandler < Kemal::BaseLogHandler
-  def initialize(@io : IO = STDOUT, @level = LogLevel::Debug)
+  def initialize(@io : IO = STDOUT, @level = LogLevel::Debug, @color : Bool = true)
   end
 
   def call(context : HTTP::Server::Context)
@@ -39,10 +41,23 @@ class Invidious::LogHandler < Kemal::BaseLogHandler
     @io.flush
   end
 
+  def color(level)
+    case level
+    when LogLevel::Trace then :cyan
+    when LogLevel::Debug then :green
+    when LogLevel::Info  then :white
+    when LogLevel::Warn  then :yellow
+    when LogLevel::Error then :red
+    when LogLevel::Fatal then :magenta
+    else                      :default
+    end
+  end
+
   {% for level in %w(trace debug info warn error fatal) %}
     def {{level.id}}(message : String)
       if LogLevel::{{level.id.capitalize}} >= @level
-        puts("#{Time.utc} [{{level.id}}] #{message}")
+        puts("#{Time.utc} [{{level.id}}] #{message}".colorize(color(LogLevel::{{level.id.capitalize}})).toggle(@color))
+
       end
     end
   {% end %}