修改了list方法的实现

@@ -5,45 +5,45 @@ local get_servers = upstream.get_servers
 local get_upstreams = upstream.get_upstreams
 local cache=ngx.shared.upstream
 
-
-function list() 
-  local t={}
-  local us=get_upstreams()
+-- get all peers for upstram: u
+function list(u)
   
-  for _,u in ipairs(us) do
-    local peers,err = upstream.get_primary_peers(u)
-    if err then
-       ngx.say("failed to get servers in upstream ", u)
+  local d={} 
+  d["name"]=u    
+  d["value"]={}
+
+  -- get primary peers
+  local peers,err = upstream.get_primary_peers(u)
+  if err then
+       ngx.say("failed to get primary servers in upstream ", u)
        return
-    end
-    local d={} 
-    d["name"]=u    
-    d["value"]={}
-    for _,p in ipairs(peers) do 
+  end
+  for _,p in ipairs(peers) do 
       local s={}   
       s["id"]=p.id
       s["down"]=p.down and p.down or false
       s["name"]=p.name
       s["backup"]=false
       table.insert(d["value"],s) 
-    end 
-    peers,err = upstream.get_backup_peers(u)
-    if err then
-       ngx.say("failed to get servers in upstream ", u)
+  end 
+
+  -- get backup peers
+  peers,err = upstream.get_backup_peers(u)
+  if err then
+       ngx.say("failed to get backup servers in upstream ", u)
        return
-    end
-    for _,p in ipairs(peers) do 
+  end
+  for _,p in ipairs(peers) do 
       local s={}   
       s["id"]=p.id
       s["down"]=p.down and p.down or false
       s["name"]=p.name
       s["backup"]=true
       table.insert(d["value"],s) 
-    end 
-    table.insert(t,d)
-  end
+  end 
+  
   ngx.header["Content-type"]="application/json;charset=utf-8"  
-  ngx.say(json.encode(t))
+  ngx.say(json.encode(d))
 end
 
 
@@ -68,7 +68,8 @@ end
 local args=ngx.req.get_uri_args()
 local method=args["method"]
 if method == "list" then
-  list()
+  local u_name = args["upstream"]
+  list(u_name)
 elseif(method=="down" or method=="up") then
   local upstream=args["upstream"]
   local backup=args["backup"]=="true" and true or false

@@ -11,4 +11,14 @@
  - `Remove blocked ip`: http://erp.yoho.yohoops.org/malIp?method=pubDel&ips=1.2.3.4,1.2.3.5
  - `Add to block ip`:  http://erp.yoho.yohoops.org/malIp?method=pubAdd&ips=1.2.3.4,1.2.3.5&expire=110000
  - `Remove all block ip`:  http://erp.yoho.yohoops.org/malIp?method=flushAll
- - `Retrive all block ip`: http://erp.yoho.yohoops.org/malIp?method=queryAll
\ No newline at end of file
+ - `Retrive all block ip`: http://erp.yoho.yohoops.org/malIp?method=queryAll
+
+
+
+## 动态`upstream`的支持
+
+基于 [lua-upstream-nginx-module] (https://github.com/openresty/lua-upstream-nginx-module) 动态设置upstream的 `up`, `down`
+
+ - 查询所有的`upstreams`信息： `curl -i -H "Host: api.yoho.cn" "http://127.0.0.1/upstreams?method=list&upstream=apigateway"`
+ - 设置 `upstream` 名称为 `apigateway`的`upstream` 第0个 `backend server` 状态为`down`： `curl -i -H "Host: api.yoho.cn" "http://127.0.0.1/upstreams?method=down&upstream=apigateway&id=0"`
+ - 设置`upstream` 名称为 `apigateway`的`upstream` 第0个 `backend server` 状态为`up`:  `curl -i -H "Host: api.yoho.cn" "http://127.0.0.1/upstreams?method=up&upstream=apigateway&id=0"`