Use log module for Crystal 0.34

Author: bcardiff

src/logger.cr

@@ -8,58 +8,105 @@ module Shards
   end
 end
 
-# Using Crystal < 0.34 logger module
+{% if compare_versions(Crystal::VERSION, "0.34.0-0") > 0 %}
+  require "log"
 
-require "logger"
+  Log.setup_from_env(
+    level: ENV.fetch("CRYSTAL_LOG_LEVEL", "INFO"),
+    sources: ENV.fetch("CRYSTAL_LOG_SOURCES", "shards.*"),
+    backend: Log::IOBackend.new.tap do |backend|
+      backend.formatter = Shards::FORMATTER
+    end
+  )
 
-module Shards
-  LOGGER_COLORS = {
-    "ERROR" => :red,
-    "WARN"  => :light_yellow,
-    "INFO"  => :light_green,
-    "DEBUG" => :light_gray,
-  }
-
-  @@logger : Logger?
-
-  def self.logger
-    @@logger ||= Logger.new(STDOUT).tap do |logger|
-      logger.progname = "shards"
-      logger.level = Logger::Severity::INFO
-
-      logger.formatter = Logger::Formatter.new do |severity, _datetime, _progname, message, io|
-        if @@colors
-          io << if color = LOGGER_COLORS[severity.to_s]?
-            if idx = message.index(' ')
-              message[0...idx].colorize(color).to_s + message[idx..-1]
-            else
-              message.colorize(color)
-            end
+  module Shards
+    Log = ::Log.for(self)
+
+    def self.set_warning_log_level
+      Log.level = ::Log::Severity::Warning
+    end
+
+    def self.set_debug_log_level
+      Log.level = ::Log::Severity::Debug
+    end
+
+    LOGGER_COLORS = {
+      ::Log::Severity::Error   => :red,
+      ::Log::Severity::Warning => :light_yellow,
+      ::Log::Severity::Info    => :light_green,
+      ::Log::Severity::Debug   => :light_gray,
+    }
+
+    FORMATTER = ::Log::Formatter.new do |entry, io|
+      message = entry.message
+
+      if @@colors
+        io << if color = LOGGER_COLORS[entry.severity]?
+          if idx = message.index(' ')
+            message[0...idx].colorize(color).to_s + message[idx..-1]
           else
-            message
+            message.colorize(color)
           end
         else
-          io << severity.to_s[0] << ": " << message
+          message
         end
+      else
+        io << entry.severity.label[0] << ": " << message
       end
     end
   end
+{% else %}
+  require "logger"
 
-  def self.set_warning_log_level
-    logger.level = Logger::Severity::WARN
-  end
+  module Shards
+    LOGGER_COLORS = {
+      "ERROR" => :red,
+      "WARN"  => :light_yellow,
+      "INFO"  => :light_green,
+      "DEBUG" => :light_gray,
+    }
 
-  def self.set_debug_log_level
-    logger.level = Logger::Severity::DEBUG
-  end
+    @@logger : Logger?
+
+    def self.logger
+      @@logger ||= Logger.new(STDOUT).tap do |logger|
+        logger.progname = "shards"
+        logger.level = Logger::Severity::INFO
 
-  module Log
-    {% for severity in %w(debug info warn error fatal) %}
-      def self.{{severity.id}}
-        Shards.logger.{{severity.id}} do
-          yield
+        logger.formatter = Logger::Formatter.new do |severity, _datetime, _progname, message, io|
+          if @@colors
+            io << if color = LOGGER_COLORS[severity.to_s]?
+              if idx = message.index(' ')
+                message[0...idx].colorize(color).to_s + message[idx..-1]
+              else
+                message.colorize(color)
+              end
+            else
+              message
+            end
+          else
+            io << severity.to_s[0] << ": " << message
+          end
         end
       end
-    {% end %}
+    end
+
+    def self.set_warning_log_level
+      logger.level = Logger::Severity::WARN
+    end
+
+    def self.set_debug_log_level
+      logger.level = Logger::Severity::DEBUG
+    end
+
+    module Log
+      {% for severity in %w(debug info warn error fatal) %}
+        def self.{{severity.id}}
+          Shards.logger.{{severity.id}} do
+            yield
+          end
+        end
+      {% end %}
+    end
   end
-end
+{% end %}