optimize: use buffer for plugin syslog. (#1551)

Author: Ayeshmantha Perera

apisix/plugins/syslog.lua

@@ -16,23 +16,28 @@
 --
 local core = require("apisix.core")
 local log_util = require("apisix.utils.log-util")
+local batch_processor = require("apisix.utils.batch-processor")
 local logger_socket = require("resty.logger.socket")
 local plugin_name = "syslog"
 local ngx = ngx
+local buffers = {}
 
 local schema = {
     type = "object",
     properties = {
         host = {type = "string"},
         port = {type = "integer"},
+        name = {type = "string", default = "sys logger"},
         flush_limit = {type = "integer", minimum = 1, default = 4096},
         drop_limit = {type = "integer", default = 1048576},
         timeout = {type = "integer", minimum = 1, default = 3},
         sock_type = {type = "string", default = "tcp"},
-        max_retry_times = {type = "integer", minimum = 1, default = 3},
-        retry_interval = {type = "integer", minimum = 10, default = 100},
+        max_retry_times = {type = "integer", minimum = 1, default = 1},
+        retry_interval = {type = "integer", minimum = 0, default = 1},
         pool_size = {type = "integer", minimum = 5, default = 5},
         tls = {type = "boolean", default = false},
+        batch_max_size = {type = "integer", minimum = 1, default = 1000},
+        buffer_duration = {type = "integer", minimum = 1, default = 60},
     },
     required = {"host", "port"}
 }
@@ -59,14 +64,9 @@ function _M.flush_syslog(logger)
     end
 end
 
--- log phase in APISIX
-function _M.log(conf)
-    local entry = log_util.get_full_log(ngx)
-
-    if not entry.route_id then
-        core.log.error("failed to obtain the route id for sys logger")
-        return
-    end
+local function send_syslog_data(conf, log_message)
+    local err_msg
+    local res = true
 
     -- fetch api_ctx
     local api_ctx = ngx.ctx.api_ctx
@@ -91,14 +91,72 @@ function _M.log(conf)
         })
 
     if not logger then
-        core.log.error("failed when initiating the sys logger processor", err)
+        res = false
+        err_msg = "failed when initiating the sys logger processor".. err
     end
 
     -- reuse the logger object
-    local ok, err = logger:log(core.json.encode(entry))
+    local ok, err = logger:log(core.json.encode(log_message))
     if not ok then
-        core.log.error("failed to log message", err)
+        res = false
+        err_msg = "failed to log message" .. err
+    end
+
+    return res, err_msg
+end
+
+-- log phase in APISIX
+function _M.log(conf)
+    local entry = log_util.get_full_log(ngx)
+
+    if not entry.route_id then
+        core.log.error("failed to obtain the route id for sys logger")
+        return
     end
+
+    local log_buffer = buffers[entry.route_id]
+
+    if log_buffer then
+        log_buffer:push(entry)
+        return
+    end
+
+    -- Generate a function to be executed by the batch processor
+    local func = function(entries, batch_max_size)
+        local data, err
+        if batch_max_size == 1 then
+            data, err = core.json.encode(entries[1]) -- encode as single {}
+        else
+            data, err = core.json.encode(entries) -- encode as array [{}]
+        end
+
+        if not data then
+            return false, 'error occurred while encoding the data: ' .. err
+        end
+
+        return send_syslog_data(conf, data)
+    end
+
+    local config = {
+        name = conf.name,
+        retry_delay = conf.retry_interval,
+        batch_max_size = conf.batch_max_size,
+        max_retry_count = conf.max_retry_times,
+        buffer_duration = conf.buffer_duration,
+        inactive_timeout = conf.timeout,
+    }
+
+    local err
+    log_buffer, err = batch_processor:new(func, config)
+
+    if not log_buffer then
+        core.log.error("error when creating the batch processor: ", err)
+        return
+    end
+
+    buffers[entry.route_id] = log_buffer
+    log_buffer:push(entry)
+
 end
 
 return _M