| -- |
| -- Licensed to the Apache Software Foundation (ASF) under one or more |
| -- contributor license agreements. See the NOTICE file distributed with |
| -- this work for additional information regarding copyright ownership. |
| -- The ASF licenses this file to You 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. |
| -- |
| local limit_conn_new = require("resty.limit.conn").new |
| local core = require("apisix.core") |
| local sleep = core.sleep |
| local plugin_name = "limit-conn" |
| |
| |
| local lrucache = core.lrucache.new({ |
| type = "plugin", |
| }) |
| |
| local schema = { |
| type = "object", |
| properties = { |
| conn = {type = "integer", exclusiveMinimum = 0}, |
| burst = {type = "integer", minimum = 0}, |
| default_conn_delay = {type = "number", exclusiveMinimum = 0}, |
| key = {type = "string", |
| enum = {"remote_addr", "server_addr", "http_x_real_ip", |
| "http_x_forwarded_for", "consumer_name"}, |
| }, |
| rejected_code = { |
| type = "integer", minimum = 200, maximum = 599, default = 503 |
| }, |
| }, |
| required = {"conn", "burst", "default_conn_delay", "key"} |
| } |
| |
| |
| local _M = { |
| version = 0.1, |
| priority = 1003, |
| name = plugin_name, |
| schema = schema, |
| } |
| |
| function _M.check_schema(conf) |
| local ok, err = core.schema.check(schema, conf) |
| if not ok then |
| return false, err |
| end |
| |
| return true |
| end |
| |
| local function create_limit_obj(conf) |
| core.log.info("create new limit-conn plugin instance") |
| return limit_conn_new("plugin-limit-conn", conf.conn, conf.burst, |
| conf.default_conn_delay) |
| end |
| |
| |
| function _M.access(conf, ctx) |
| core.log.info("ver: ", ctx.conf_version) |
| local lim, err = lrucache(conf, nil, create_limit_obj, conf) |
| if not lim then |
| core.log.error("failed to instantiate a resty.limit.conn object: ", err) |
| return 500 |
| end |
| |
| local key = (ctx.var[conf.key] or "") .. ctx.conf_type .. ctx.conf_version |
| core.log.info("limit key: ", key) |
| |
| local delay, err = lim:incoming(key, true) |
| if not delay then |
| if err == "rejected" then |
| return conf.rejected_code |
| end |
| |
| core.log.error("failed to limit req: ", err) |
| return 500 |
| end |
| |
| if lim:is_committed() then |
| if not ctx.limit_conn then |
| ctx.limit_conn = core.tablepool.fetch("plugin#limit-conn", 0, 6) |
| end |
| |
| core.table.insert_tail(ctx.limit_conn, lim, key, delay) |
| end |
| |
| if delay >= 0.001 then |
| sleep(delay) |
| end |
| end |
| |
| |
| function _M.log(conf, ctx) |
| local limit_conn = ctx.limit_conn |
| if not limit_conn then |
| return |
| end |
| |
| for i = 1, #limit_conn, 3 do |
| local lim = limit_conn[i] |
| local key = limit_conn[i + 1] |
| local delay = limit_conn[i + 2] |
| |
| local latency |
| if ctx.proxy_passed then |
| latency = ctx.var.upstream_response_time |
| else |
| latency = ctx.var.request_time - delay |
| end |
| |
| core.log.debug("request latency is ", latency) -- for test |
| |
| local conn, err = lim:leaving(key, latency) |
| if not conn then |
| core.log.error("failed to record the connection leaving request: ", |
| err) |
| break |
| end |
| end |
| |
| core.tablepool.release("plugin#limit-conn", limit_conn) |
| return |
| end |
| |
| |
| return _M |