Add the AccessLogFilter into default filters and add example in comments of acccess_log_filter

common/constant/default.go

@@ -46,7 +46,7 @@ const (
 const (
 	DEFAULT_KEY               = "default"
 	PREFIX_DEFAULT_KEY        = "default."
-	DEFAULT_SERVICE_FILTERS   = "echo,token"
+	DEFAULT_SERVICE_FILTERS   = "echo,token,accesslog"
 	DEFAULT_REFERENCE_FILTERS = ""
 	GENERIC_REFERENCE_FILTERS = "generic"
 	GENERIC                   = "$invoke"

examples/general/dubbo/go-server/profiles/dev/server.yml

@@ -25,9 +25,6 @@ registries :
     username: ""
     password: ""
 
-# config your filter. for example, you wish to use the access log filter
-#filter: "accesslog"
-
 services:
   "UserProvider":
     # 可以指定多个registry，使用逗号隔开;不指定默认向所有注册中心注册

filter/impl/access_log_filter.go

@@ -48,6 +48,22 @@ func init() {
 	extension.SetFilter(constant.ACCESS_LOG_KEY, GetAccessLogFilter)
 }
 
+/*
+ * Although the access log filter is a default filter,
+ * you should config "accesslog" in service's config to tell the filter where store the access log.
+ * for example:
+ * "UserProvider":
+    # 可以指定多个registry，使用逗号隔开;不指定默认向所有注册中心注册
+    registry: "hangzhouzk"
+    protocol : "dubbo"
+    # 相当于dubbo.xml中的interface
+    interface : "com.ikurento.user.UserProvider"
+    ... # other configuration
+    accesslog: "/your/path/to/store/the/log/", # it should be the path of file.
+
+ * the value of "accesslog" can be "true" or "default" too.
+ * If the value is one of them, the access log will be record in log file which defined in log.yml
+*/
 type AccessLogFilter struct {
 	logChan chan AccessLogData
 }