feat: server info

apisix/admin/init.lua

@@ -18,6 +18,7 @@ local require = require
 local core = require("apisix.core")
 local route = require("resty.radixtree")
 local plugin = require("apisix.plugin")
+
 local ngx = ngx
 local get_method = ngx.req.get_method
 local ngx_time = ngx.time
@@ -29,6 +30,7 @@ local reload_event = "/apisix/admin/plugins/reload"
 local ipairs = ipairs
 local error = error
 local events
+
 local MAX_REQ_BODY = 1024 * 1024 * 1.5      -- 1.5 MiB
 
 

apisix/cli/ngx_tpl.lua

@@ -111,6 +111,7 @@ http {
                       .. [=[$prefix/deps/lib/lua/5.1/?.so;;]=]
                       .. [=[{*lua_cpath*};";
 
+    lua_shared_dict internal_status      10m;
     lua_shared_dict plugin-limit-req     10m;
     lua_shared_dict plugin-limit-count   10m;
     lua_shared_dict prometheus-metrics   10m;

apisix/core/utils.lua

@@ -14,28 +14,36 @@
 -- See the License for the specific language governing permissions and
 -- limitations under the License.
 --
-local table    = require("apisix.core.table")
-local ngx_re   = require("ngx.re")
-local resolver = require("resty.dns.resolver")
-local ipmatcher= require("resty.ipmatcher")
-local ffi      = require("ffi")
-local base     = require("resty.core.base")
+local table     = require("apisix.core.table")
+local log       = require("apisix.core.log")
+local ngx_re    = require("ngx.re")
+local resolver  = require("resty.dns.resolver")
+local ipmatcher = require("resty.ipmatcher")
+local ffi       = require("ffi")
+local base      = require("resty.core.base")
+
 local open     = io.open
 local math     = math
 local sub_str  = string.sub
 local str_byte = string.byte
 local tonumber = tonumber
 local type     = type
 local C        = ffi.C
-local ffi_string = ffi.string
+
+local ffi_string     = ffi.string
 local get_string_buf = base.get_string_buf
-local exiting = ngx.worker.exiting
-local ngx_sleep    = ngx.sleep
+local exiting        = ngx.worker.exiting
+local ngx_sleep      = ngx.sleep
+
+local hostname
 local max_sleep_interval = 1
+local max_hostname_len = 256
 
 ffi.cdef[[
     int ngx_escape_uri(char *dst, const char *src,
         size_t size, int type);
+    int gethostname(char *name, size_t len);
+    int strlen(const char *s);
 ]]
 
 
@@ -203,6 +211,26 @@ function _M.validate_header_value(value)
 end
 
 
+function _M.gethostname()
+    if hostname then
+        return hostname
+    end
+
+    local buf = get_string_buf(max_hostname_len)
+
+    if C.gethostname(buf, max_hostname_len) == 0 then
+        buf[max_hostname_len - 1] = str_byte('\0')
+        hostname = ffi_string(buf, ffi.C.strlen(buf))
+
+    else
+        log.alert("ffi.C.gethostname() failed")
+        hostname = "unknown"
+    end
+
+    return hostname
+end
+
+
 local function sleep(sec)
     if sec <= max_sleep_interval then
         return ngx_sleep(sec)

apisix/init.lua

@@ -111,6 +111,7 @@ function _M.http_init_worker()
 
     require("apisix.debug").init_worker()
     require("apisix.upstream").init_worker()
+    require("apisix.server_info").init_worker()
 
     local_conf = core.config.local_conf()
     local dns_resolver_valid = local_conf and local_conf.apisix and

apisix/plugins/server-info.lua

@@ -0,0 +1,67 @@
+--
+-- 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 server_info = require("apisix.server_info")
+local core = require("apisix.core")
+
+local plugin_name = "server-info"
+local schema = {
+    type = "object",
+    additionalProperties = false,
+}
+
+
+local _M = {
+    version = 0.1,
+    priority = 1000,
+    name = plugin_name,
+    schema = schema,
+}
+
+
+local function get_server_info()
+    local server_info, err = server_info.get()
+    if not server_info then
+        core.log.error("failed to get server_info: ", err)
+        return 500, err
+    end
+
+    return 200, core.json.encode(server_info)
+end
+
+
+function _M.check_schema(conf)
+    local ok, err = core.schema.check(schema, conf)
+    if not ok then
+        return false, err
+    end
+
+    return true
+end
+
+
+function _M.api()
+    return {
+        {
+            methods = {"GET"},
+            uri = "/apisix/server_info",
+            handler = get_server_info,
+        },
+    }
+end
+
+
+return _M

apisix/server_info.lua

@@ -0,0 +1,168 @@
+--
+-- 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 require = require
+local core = require("apisix.core")
+
+local type = type
+local ngx_time = ngx.time
+
+local boot_time = os.time()
+local internal_status = ngx.shared.internal_status
+
+local _M = {}
+
+if not internal_status then
+    error("lua_shared_dict \"internal_status\" not configured")
+end
+
+
+local function is_privileged()
+    local process_type = require("ngx.process").type()
+    return process_type == "privileged agent" or process_type == "single"
+end
+
+-- server information will be saved into shared memory only if the key
+-- "server_info" not exist if excl is true.
+local function save(data, excl)
+    local handler = excl and internal_status.add or internal_status.set
+
+    local ok, err = handler(internal_status, "server_info", data)
+    if not ok then
+        if excl and err == "exists" then
+            return true
+        end
+
+        return nil, err
+    end
+
+    return true
+end
+
+
+local function encode_and_save(server_info, excl)
+    local data, err = core.json.encode(server_info)
+    if not data then
+        return nil, err
+    end
+
+    return save(data, excl)
+end
+
+
+local function report()
+    local server_info, err = _M.get()
+    if not server_info then
+        core.log.error("failed to get server_info: ", err)
+        return nil, err
+    end
+
+    if server_info.etcd_version == "unknown" then
+        local res, err = core.etcd.server_version()
+        if not res then
+            core.log.error("failed to fetch etcd version: ", err)
+            return nil, err
+
+        elseif type(res.body) ~= "table" then
+            core.log.error("failed to fetch etcd version: bad version info")
+            return nil, "bad etcd version info"
+        else
+            server_info.etcd_version = res.body.etcdcluster
+        end
+    end
+
+    server_info.last_report_time = ngx_time()
+
+    local data, err = core.json.encode(server_info)
+    if not data then
+        core.log.error("failed to encode server_info: ", err)
+        return nil, err
+    end
+
+    local key = "/data_plane/server_info/" .. server_info.id
+    local ok, err = core.etcd.set(key, data, 180)
+    if not ok then
+        core.log.error("failed to report server info to etcd: ", err)
+        return nil, err
+    end
+
+    local ok, err = save(data, false)
+    if not ok then
+        core.log.error("failed to encode and save server info: ", err)
+        return nil, err
+    end
+end
+
+
+local function uninitialized_server_info()
+    return {
+        etcd_version     = "unknown",
+        hostname         = core.utils.gethostname(),
+        id               = core.id.get(),
+        version          = core.version.VERSION,
+        up_time          = ngx_time() - boot_time,
+        last_report_time = -1,
+    }
+end
+
+
+function _M.init_worker()
+    if not is_privileged() then
+        return
+    end
+
+    local ok, err = encode_and_save(uninitialized_server_info(), true)
+    if not ok then
+        core.log.error("failed to encode and save server info: ", err)
+    end
+
+    local opts = {
+        check_interval = 5, -- in seconds
+    }
+
+    if core.config ~= require("apisix.core.config_etcd") then
+        return
+    end
+
+    -- only launch timer to report server info when config cener is etcd.
+    local timer, err = core.timer.new("server info", report, opts)
+    if not timer then
+        core.log.error("failed to create timer to report server info ", err)
+    end
+end
+
+
+function _M.get()
+    local data, err = internal_status:get("server_info")
+    if err ~= nil then
+        return nil, err
+    end
+
+    if not data then
+        return uninitialized_server_info()
+    end
+
+    local server_info, err = core.json.decode(data)
+    if not server_info then
+        return nil, err
+    end
+
+    server_info.up_time = ngx_time() - boot_time
+    return server_info
+end
+
+
+return _M

conf/config-default.yaml

@@ -215,6 +215,7 @@ plugins:                          # plugin list
   - sls-logger
   - hmac-auth
   - api-breaker
+  - server-info
 
 stream_plugins:
   - mqtt-proxy