lua-resty-healthcheck
A health check library for OpenResty.
Status
This library is still under early development.
Synopsis
http { lua_shared_dict test_shm 8m; lua_shared_dict my_worker_events 8m; init_worker_by_lua_block { local we = require "resty.worker.events" local ok, err = we.configure{ shm = "my_worker_events", interval = 0.1, } if not ok then ngx.log(ngx.ERR, "failed to configure worker events: ", err) return end ngx.timer.at(0, function() local healthcheck = require("resty.healthcheck") local checker = healthcheck.new({ name = "test_checker", shm_name = "test_shm", checks = { active = { http_request = "GET /status HTTP/1.0\r\nHost: example.com\r\n\r\n", healthy = { interval = 0.5 }, unhealthy = { interval = 0.5 } } } }) local handler = function(target, eventname, sourcename, pid) ngx.log(ngx.DEBUG,"Event from: ", sourcename) if eventname == checker.events.remove -- a target was removed ngx.log(ngx.DEBUG,"Target removed: ", target.ip, ":", target.port, " ", target.hostname) elseif eventname == checker.events.healthy -- target changed state, or was added ngx.log(ngx.DEBUG,"Target switched to healthy: ", target.ip, ":", target.port, " ", target.hostname) elseif eventname == checker.events.unhealthy -- target changed state, or was added ngx.log(ngx.DEBUG,"Target switched to unhealthy: ", target.ip, ":", target.port, " ", target.hostname) else -- unknown event end end we.register(handler, checker.EVENT_SOURCE) local ok, err = checker:add_target("127.0.0.1", 2112) if not ok then ngx.log(ngx.ERR, err) end local ok, err = checker:add_target("127.0.0.1", 5150) if not ok then ngx.log(ngx.ERR, err) end end) } }
Description
This library supports performing active and passive health checks on arbitrary hosts.
Control of the library happens via its programmatic API. Consumption of its events happens via the lua-resty-worker-events library.
Targets are added using checker:add_target(host, port)
.
Changes in status ("healthy" or "unhealthy") are broadcasted via worker-events.
Active checks are executed in the background based on the specified timer intervals.
For passive health checks, the library receives explicit notifications via its
programmatic API using functions such as checker:report_http_status(host, port, status)
.
See the online LDoc documentation for the complete API.
History
0.4.0 (20-Mar-2017)
- Correct setting of defaults in
http_statuses
- Type and bounds checking to
checks
table
0.3.0 (18-Dec-2017)
- Disable individual checks by setting their counters to 0
0.2.0 (30-Nov-2017)
- Adds
set_target_status
0.1.0 (27-Nov-2017) Initial release
- Initial upload
Copyright and License
Copyright 2017 Kong Inc.
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.