optimize: used lua table to cache the ngx variable.

lua/apisix.lua

@@ -43,7 +43,7 @@ local function run_plugin(phase, filter_plugins, api_ctx)
 
     for i = 1, #filter_plugins, 2 do
         local phase_fun = filter_plugins[i][phase]
-        if  phase_fun then
+        if phase_fun then
             local code, body = phase_fun(filter_plugins[i + 1], api_ctx)
             if phase ~= "log" and type(code) == "number" or body then
                 core.response.exit(code, body)
@@ -62,9 +62,10 @@ function _M.rewrite_phase()
         api_ctx = new_tab(0, 32)
     end
 
-    local method = core.request.var(api_ctx, "method")
-    local uri = core.request.var(api_ctx, "uri")
-    -- local host = core.request.var(api_ctx, "host") -- todo: support host
+    core.ctx.set_vars_meta(api_ctx)
+    local method = api_ctx.var["method"]
+    local uri =  api_ctx.var["uri"]
+    -- local host = api_ctx.var["host"] -- todo: support host
 
     -- run the api router
     local api_router = plugin.api_router()

lua/apisix/core.lua

@@ -57,4 +57,5 @@ return {
     typeof   = require("apisix.core.typeof"),
     lrucache = require("apisix.core.lrucache"),
     schema   = require("apisix.core.schema"),
+    ctx      = require("apisix.core.ctx"),
 }

lua/apisix/core/ctx.lua

@@ -0,0 +1,40 @@
+local new_tab = require("table.new")
+local ngx_var = ngx.var
+
+
+local _M = {version = 0.1}
+
+
+do
+    local var_methods = {
+        ["method"] = ngx.req.get_method
+    }
+
+    local mt = {
+        __index = function(t, name)
+            local val
+            local method = var_methods[name]
+            if method then
+                val = method()
+
+            else
+                val = ngx_var[name]
+            end
+
+            if val then
+                t[name] = val
+            end
+
+            return val
+        end
+    }
+
+function _M.set_vars_meta(ctx)
+    ctx.var = new_tab(0, 32)
+    setmetatable(ctx.var, mt)
+end
+
+end -- do
+
+
+return _M

lua/apisix/core/request.lua

@@ -2,53 +2,25 @@
 
 local ngx = ngx
 local get_headers = ngx.req.get_headers
-local ngx_var = ngx.var
-local new_tab = require("table.new")
-local var_methods = {
-    -- todo: support more type
-    method = ngx.req.get_method
-}
 
 
 local _M = {version = 0.1}
 
 
-function _M.header(ctx, name)
+local function _headers(ctx)
     local headers = ctx.headers
     if not headers then
         headers = get_headers()
         ctx.headers = headers
     end
 
-    return ctx.headers[name]
+    return headers
 end
+_M.headers = _headers
 
 
-function _M.var(ctx, name)
-    local vars = ctx.vars
-    if not vars then
-        vars = new_tab(0, 8)
-        ctx.vars = vars
-    end
-
-    local val = vars[name]
-    if val then
-        return val
-    end
-
-    -- todo: support more data type
-    local method = var_methods[name]
-    if method then
-        val = method()
-    else
-        val = ngx_var[name]
-    end
-
-    if val then
-        vars[name] = val
-    end
-
-    return val
+function _M.header(ctx, name)
+    return _headers(ctx)[name]
 end
 
 

lua/apisix/plugin.lua

@@ -120,25 +120,23 @@ end
 
 
 function _M.merge_service_route(service_conf, route_conf)
-    -- core.log.warn("base conf: ", core.json.encode(base_conf))
-    -- core.log.warn("new  conf: ", core.json.encode(new_conf))
-    local new_conf = false
-    if service_conf.plugin_config and
-       core.table.nkeys(service_conf.plugin_config) then
-        for name, conf in pairs(service_conf.plugin_config) do
-            route_conf.plugin_config[name] = conf
+    local changed = false
+    if route_conf.value.plugin_config and
+       core.table.nkeys(route_conf.value.plugin_config) then
+        for name, conf in pairs(route_conf.value.plugin_config) do
+            service_conf.value.plugin_config[name] = conf
         end
-        new_conf = true
+        changed = true
     end
 
-    if service_conf.upstream and core.table.nkeys(service_conf.upstream) then
-        route_conf.upstream = service_conf.upstream
-        new_conf = true
+    if route_conf.upstream and core.table.nkeys(route_conf.upstream) then
+        service_conf.upstream = route_conf.upstream
+        changed = true
     end
 
     route_conf.service = service_conf.value
 
-    return service_conf, new_conf
+    return service_conf, changed
 end
 
 

lua/apisix/plugins/limit-count.lua

@@ -27,7 +27,7 @@ function _M.access(conf, ctx)
     local limit = core.lrucache.plugin_ctx(plugin_name, ctx,
                                            create_limit_obj, conf)
 
-    local key = core.request.var(ctx, conf.key)
+    local key = ctx.var[conf.key]
     if not key or key == "" then
         key = ""
         core.log.warn("fetched empty string value as key to limit the request ",

lua/apisix/plugins/limit-req.lua

@@ -25,7 +25,7 @@ function _M.access(conf, ctx)
     local limit_ins = core.lrucache.plugin_ctx(plugin_name, ctx,
                                                create_limit_obj, conf)
 
-    local key = core.request.var(ctx, conf.key)
+    local key = ctx.var[conf.key]
     if not key or key == "" then
         key = ""
         core.log.warn("fetched empty string value as key to limit the request ",

lua/apisix/plugins/prometheus/exporter.lua

@@ -23,8 +23,8 @@ do
 
 function _M.log(conf, ctx)
     core.table.clear(tmp_tab)
-    tmp_tab[1] = ngx.status
-    tmp_tab[2] = ngx.var.host
+    tmp_tab[1] = ctx.var.status
+    tmp_tab[2] = ctx.var.host
     metrics.status:inc(1, tmp_tab)
 
     core.log.warn("hit prometheuse plugin")