Updated Filer Change Data Capture (markdown)

Filer-Change-Data-Capture.md

@@ -7,9 +7,13 @@ Actually SeaweedFS can give you more!
 You can watch the SeaweedFS meta data changes.
 
 ```
-$ weed watch -h
-Example: weed watch [-filer=localhost:8888] [-target=/]
+$ weed filer.meta.tail -h
+Example: weed filer.meta.tail [-filer=localhost:8888] [-target=/]
 Default Usage:
+  -es string
+    	comma-separated elastic servers http://<host:port>
+  -es.index string
+    	ES index name (default "seaweedfs")
   -filer string
     	filer hostname:port (default "localhost:8888")
   -pathPrefix string
@@ -21,13 +25,18 @@ Default Usage:
 Description:
   See recent changes on a filer.
 
-$ weed watch
+$ weed filer.meta.tail
 dir:/home new_entry:{name:"3190.pdf" chunks:{size:1130805 mtime:1608763500740201000 e_tag:"5c745d0a109bde58e0baaa6515c3694a" fid:{volume_id:1 file_key:35 cookie:4265699614}} attributes:{file_size:1130805 mtime:1608763500 file_mode:432 uid:502 gid:20 crtime:1608763500 mime:"application/pdf" replication:"000" md5:"\\t]\n\x10\x9b\xdeXສe\x15\xc3iJ"}} delete_chunks:true new_parent_path:"/home" signatures:1622972984
 ```
 
+If configured Elastic Search server names, the meta data will be sent to Elastic Search
+```
+$ weed filer.meta.tail -es=http://localhost:9200
+```
+
 # How it works?
 
-The `weed watch` code is nothing fancy. It is calls a gRPC stream API to subscribe to all meta data changes and simply print out the meta data.
+The `weed filer.meta.tail` code is nothing fancy. It is calls a gRPC stream API to subscribe to all meta data changes and simply print out the meta data.
 
 The gRPC API has several important use cases within SeaweedFS:
 * Replicate data to other SeaweedFS clusters in `weed filer.sync`.