Allow log level to be overridden per file

lib/solargraph/logging.rb

@@ -29,9 +29,26 @@ module Logging
 
     module_function
 
+    # override this in your class to temporarily set a custom
+    # filtering log level for the class (e.g., suppress any debug
+    # message by setting it to :info even if it is set elsewhere, or
+    # show existing debug messages by setting to :debug).
+    #
+    # @return [Symbol]
+    def log_level
+      :warn
+    end
+
     # @return [Logger]
     def logger
-      @@logger
+      if LOG_LEVELS[log_level.to_s] == DEFAULT_LOG_LEVEL
+        @@logger
+      else
+        new_log_level = LOG_LEVELS[log_level.to_s]
+        logger = Logger.new(STDERR, level: new_log_level)
+        logger.formatter = @@logger.formatter
+        logger
+      end
     end
   end
 end