diff options
| author |   HuabingZhao <zhaohuabing@zte.com.cn> | 2016-08-13 14:10:39 +0800 |
|---|---|---|
| committer |   HuabingZhao <zhao.huabing@zte.com.cn> | 2016-08-13 14:56:36 +0800 |
| commit | 1ae0c8d11018ac804be96062c34fcf0d9015ef35 (patch) | |
| tree | f36880d9f409807c30d2927070c8b5dc4168843b /openresty-ext/src/assembly/resources/openresty/nginx/luaext/lib/tools/db_cache.lua | |
| parent | 29c0018a50104f18b34277cc01720c0b3e401212 (diff) | |
Initial code import
Change-Id: I839b84e5600aedece6c33deb16bec1bf9dbb61df
Signed-off-by: HuabingZhao <zhao.huabing@zte.com.cn>
Diffstat (limited to 'openresty-ext/src/assembly/resources/openresty/nginx/luaext/lib/tools/db_cache.lua')
| -rw-r--r-- | openresty-ext/src/assembly/resources/openresty/nginx/luaext/lib/tools/db_cache.lua | 54 |
1 files changed, 54 insertions, 0 deletions
diff --git a/openresty-ext/src/assembly/resources/openresty/nginx/luaext/lib/tools/db_cache.lua b/openresty-ext/src/assembly/resources/openresty/nginx/luaext/lib/tools/db_cache.lua new file mode 100644 index 0000000..7f40590 --- /dev/null +++ b/openresty-ext/src/assembly/resources/openresty/nginx/luaext/lib/tools/db_cache.lua @@ -0,0 +1,54 @@ +--[[
+
+ Copyright (C) 2016 ZTE, Inc. and others. All rights reserved. (ZTE)
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+--]]
+
+-- db cache over LRUCache， used within one worker processes
+local _M = {}
+_M._VERSION = '1.0.0'
+
+local lrucache = require "resty.lrucache"
+
+local EMPTY_DATA = '_EMPTY_'
+
+-- we need to initialize the cache on the lua module level so that
+-- it can be shared by all the requests served by each nginx worker process:
+local cache,err = lrucache.new(200) -- allow up to 200 items in the cache
+if not cache then
+ return ngx.log(ngx.ERR,"failed to create the cache: " .. (err or "unknown"))
+end
+
+function _M.get(key)
+ return cache:get(key)
+end
+
+function _M.set(key,value)
+ return _M:set(key, value, nil)
+end
+
+function _M.set(key,value,ttl)
+ if not value then
+ value = EMPTY_DATA
+ end
+ return cache:set(key, value, ttl)
+end
+
+-- check if the data returned by get() is considered empty
+function _M.is_empty(data)
+ return data == EMPTY_DATA
+end
+
+return _M
\ No newline at end of file |