optimize: returns a fetch function when creating a new lrucache obj…

…ect, which can be used directly to get cached data. (#66)

* optimize: returns a fetch function when creating a new `lrucache`
object, which can be used directly to get cached data.
* test: added test case for `core.lrucache` library.

.gitignore

@@ -45,3 +45,4 @@ logs/*.pid
 t/servroot
 go
 \.*
+conf/apisix.uid

lua/apisix/balancer.lua

@@ -4,10 +4,7 @@ local balancer = require("ngx.balancer")
 local upstreams_etcd
 local error = error
 local module_name = "balancer"
-local lrucache = core.lrucache.new{
-        plugin_ttl = 300,
-        plugin_count = 256
-    }
+local lrucache_get = core.lrucache.new({ttl = 300, count = 256})
 
 
 local _M = {
@@ -17,8 +14,8 @@ local _M = {
 
 
 local function create_server_picker(typ, nodes)
-    -- core.log.info("create create_obj, type: ", typ,
-    --               " nodes: ", core.json.encode(nodes))
+    core.log.info("create create_obj, type: ", typ,
+                  " nodes: ", core.json.delay_encode(nodes))
 
     if typ == "roundrobin" then
         return roundrobin:new(nodes)
@@ -61,7 +58,7 @@ function _M.run(route, ctx)
         key = upstream.type .. "#route_" .. route.value.id
     end
 
-    local server_picker = lrucache:plugin(module_name, key, version,
+    local server_picker = lrucache_get(key, version,
                             create_server_picker, upstream.type, upstream.nodes)
     if not server_picker then
         error("failed to fetch server picker")

lua/apisix/consumer.lua

@@ -1,6 +1,5 @@
 local lrucache = require("apisix.core.lrucache")
 local config   = require("apisix.core.config_etcd")
-local log = require("apisix.core.log")
 local insert_tab = table.insert
 local consumers
 local error = error

lua/apisix/core/lrucache.lua

@@ -2,7 +2,6 @@
 -- only support to cache lua table object
 
 local lru_new = require("resty.lrucache").new
-local setmetatable = setmetatable
 -- todo: support to config it in YAML.
 local GLOBAL_TTL = 60 * 60          -- 60 min
 local GLOBAL_ITEMS_COUNT = 1024
@@ -82,29 +81,34 @@ function _M.plugin_ctx(plugin_name, api_ctx, create_obj_fun, ...)
 end
 
 
-local function _obj_plugin_ctx(self, plugin_name, api_ctx, create_obj_fun, ...)
-    local key = api_ctx.conf_type .. "#" .. api_ctx.conf_id
-    return _plugin(self.plugin_count, self.plugin_ttl, plugin_name, key,
-                   api_ctx.conf_version, create_obj_fun, ...)
-end
-
-
-local function _obj_plugin(self, plugin_name, key, version, create_obj_fun, ...)
-    return _plugin(self.plugin_count, self.plugin_ttl, plugin_name, key,
-                   version, create_obj_fun, ...)
-end
-
-
 function _M.new(opts)
-    local plugin_count = opts and opts.plugin_count or PLUGIN_ITEMS_COUNT
-    local plugin_ttl = opts and opts.plugin_ttl or PLUGIN_TTL
-
-    return setmetatable({
-        plugin_count = plugin_count,
-        plugin_ttl = plugin_ttl,
-        plugin_ctx = _obj_plugin_ctx,
-        plugin = _obj_plugin,
-    }, mt)
+    local item_count = opts and opts.count or GLOBAL_ITEMS_COUNT
+    local item_ttl = opts and opts.ttl or GLOBAL_TTL
+
+    local lru_obj = lru_new(item_count)
+
+    return function (key, version, create_obj_fun, ...)
+        local obj, stale_obj = lru_obj:get(key)
+        if obj and obj._cache_ver == version then
+            return obj
+        end
+
+        if stale_obj and stale_obj._cache_ver == version then
+            lru_obj:set(key, obj, item_ttl)
+            return stale_obj
+        end
+
+        local err
+        obj, err = create_obj_fun(...)
+        if type(obj) == 'table' then
+            obj._cache_ver = version
+            lru_obj:set(key, obj, item_ttl)
+        else
+            log.warn('only support to cache Lua table object with lrucache')
+        end
+
+        return obj, err
+    end
 end
 
 

t/core-json.t

@@ -27,6 +27,7 @@ GET /t
 encode: {"test":"test"}
 data: test
 --- no_error_log
+[error]
 
 
 
@@ -70,3 +71,4 @@ GET /t
 --- response_body_like eval
 qr/\{"test":"test","fun":"function: 0x[0-9a-f]+"}/
 --- no_error_log
+[error]

t/core-lrucache.t

@@ -0,0 +1,121 @@
+use t::APISix 'no_plan';
+
+repeat_each(1);
+no_long_string();
+no_root_location();
+log_level("info");
+
+run_tests;
+
+__DATA__
+
+=== TEST 1: sanity
+--- config
+    location /t {
+        content_by_lua_block {
+            local core = require("apisix.core")
+
+            local idx = 0
+            local function create_obj()
+                idx = idx + 1
+                return {idx = idx}
+            end
+
+            local obj = core.lrucache.global("key", nil, create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = core.lrucache.global("key", nil, create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = core.lrucache.global("key", "1", create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+        }
+    }
+--- request
+GET /t
+--- response_body
+obj: {"idx":1}
+obj: {"idx":1}
+obj: {"idx":2,"_cache_ver":"1"}
+--- no_error_log
+[error]
+
+
+
+=== TEST 2: plugin
+--- config
+    location /t {
+        content_by_lua_block {
+            local core = require("apisix.core")
+
+            local idx = 0
+            local function create_obj()
+                idx = idx + 1
+                return {idx = idx}
+            end
+
+            local obj = core.lrucache.plugin("plugin-a", "key", nil, create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = core.lrucache.plugin("plugin-a", "key", nil, create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = core.lrucache.plugin("plugin-a", "key", "1", create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = core.lrucache.plugin("plugin-b", "key", "1", create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+        }
+    }
+--- request
+GET /t
+--- response_body
+obj: {"idx":1}
+obj: {"idx":1}
+obj: {"idx":2,"_cache_ver":"1"}
+obj: {"idx":3,"_cache_ver":"1"}
+--- no_error_log
+[error]
+
+
+
+=== TEST 3: new
+--- config
+    location /t {
+        content_by_lua_block {
+            local core = require("apisix.core")
+
+            local idx = 0
+            local function create_obj()
+                idx = idx + 1
+                return {idx = idx}
+            end
+
+            local lru_get = core.lrucache.new()
+
+            local obj = lru_get("key", nil, create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = lru_get("key", nil, create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = lru_get("key", "1", create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = lru_get("key", "1", create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+
+            obj = lru_get("key-different", "1", create_obj)
+            ngx.say("obj: ", core.json.encode(obj))
+        }
+    }
+--- request
+GET /t
+--- response_body
+obj: {"idx":1}
+obj: {"idx":1}
+obj: {"idx":2,"_cache_ver":"1"}
+obj: {"idx":2,"_cache_ver":"1"}
+obj: {"idx":3,"_cache_ver":"1"}
+--- no_error_log
+[error]