change: rename plugin's balancer method to before_proxy (#4697)

This is confusing to have plugin's balancer method and user-defined
balancer.

Signed-off-by: spacewander <spacewanderlzx@gmail.com>

apisix/balancer.lua

@@ -321,7 +321,7 @@ function _M.run(route, ctx, plugin_funcs)
             end
         end
 
-        local _, run = plugin_funcs("balancer")
+        local _, run = plugin_funcs("before_proxy")
         -- always recreate request as the request may be changed by plugins
         if (run or header_changed) and balancer.recreate_request then
             balancer.recreate_request()

apisix/init.lua

@@ -518,8 +518,8 @@ function _M.http_access_phase()
 
     set_upstream_headers(api_ctx, server)
 
-    -- run the balancer phase in access phase first to avoid always reinit request
-    common_phase("balancer")
+    -- run the before_proxy method in access phase first to avoid always reinit request
+    common_phase("before_proxy")
 
     local ref = ctxdump.stash_ngx_ctx()
     core.log.info("stash ngx ctx: ", ref)
@@ -913,8 +913,8 @@ function _M.stream_preread_phase()
 
     api_ctx.picked_server = server
 
-    -- run the balancer phase in preread phase first to avoid always reinit request
-    common_phase("balancer")
+    -- run the before_proxy method in preread phase first to avoid always reinit request
+    common_phase("before_proxy")
 end
 
 

apisix/plugins/serverless/init.lua

@@ -113,7 +113,7 @@ return function(plugin_name, priority)
         call_funcs('access', conf, ctx)
     end
 
-    function _M.balancer(conf, ctx)
+    function _M.before_proxy(conf, ctx)
         call_funcs('balancer', conf, ctx)
     end