Use standard Log handler for server logs (#303)

- Use `HTTP::LogHandler`
- Fix the logger initialization. Use `Kemal.config.logger = APILogHandler.new`
  instead of `logger APILogHandler.new` (See issue:
  kemalcr/kemal#653)

Signed-off-by: Aravinda Vishwanathapura <[email protected]>

mgr/src/server/server.cr

@@ -24,25 +24,17 @@ end
 module StorageMgr
   class StorageManagerAPILogHandler < Kemal::BaseLogHandler
     def initialize
+      @handler = HTTP::LogHandler.new
     end
 
     def call(context : HTTP::Server::Context)
-      elapsed_time = Time.measure { call_next(context) }
-      elapsed_text = elapsed_text(elapsed_time)
-      Log.info &.emit("#{context.request.method} #{context.request.resource}", status_code: "#{context.response.status_code}", duration: "#{elapsed_text}")
-      context
+      @handler.next = @next
+      @handler.call(context)
     end
 
     def write(message : String)
       Log.info { message.strip }
     end
-
-    private def elapsed_text(elapsed)
-      millis = elapsed.total_milliseconds
-      return "#{millis.round(2)}ms" if millis >= 1
-
-      "#{(millis * 1000).round(2)}µs"
-    end
   end
 
   def self.start_services
@@ -166,7 +158,7 @@ module StorageMgr
 
     Log.info &.emit("Starting the Storage manager ReST API server", port: "#{Kemal.config.port}")
 
-    logger StorageManagerAPILogHandler.new
+    Kemal.config.logger = StorageManagerAPILogHandler.new
     add_handler ApiExceptionHandler.new
     add_handler MgrRequestsProxyHandler.new
     add_handler AuthHandler.new