From 3300f4d19bb9d3ca08ea6e3e17ede71cea7eeb80 Mon Sep 17 00:00:00 2001
From: Ayeshmantha Perera <akayeshmantha@apache.org>
Date: Mon, 11 May 2020 10:28:24 +0200
Subject: [PATCH] bugfix: removed stale object in sys log. (#1557)

---
 apisix/plugins/kafka-logger.lua |  2 +-
 apisix/plugins/syslog.lua       | 26 ++++++++++++++++++++++++++
 apisix/plugins/tcp-logger.lua   |  2 +-
 apisix/plugins/udp-logger.lua   |  2 +-
 4 files changed, 29 insertions(+), 3 deletions(-)

diff --git a/apisix/plugins/kafka-logger.lua b/apisix/plugins/kafka-logger.lua
index 1641c5e1..e88cf7ca 100644
--- a/apisix/plugins/kafka-logger.lua
+++ b/apisix/plugins/kafka-logger.lua
@@ -93,7 +93,7 @@ local function send_kafka_data(conf, log_message)
     end
 end
 
-
+-- remove stale objects from the memory after timer expires
 local function remove_stale_objects(premature)
     if premature then
         return
diff --git a/apisix/plugins/syslog.lua b/apisix/plugins/syslog.lua
index 270b719b..f633f3ce 100644
--- a/apisix/plugins/syslog.lua
+++ b/apisix/plugins/syslog.lua
@@ -21,6 +21,10 @@ local logger_socket = require("resty.logger.socket")
 local plugin_name = "syslog"
 local ngx = ngx
 local buffers = {}
+local ipairs   = ipairs
+local stale_timer_running = false;
+local timer_at = ngx.timer.at
+local tostring = tostring
 
 local schema = {
     type = "object",
@@ -105,6 +109,22 @@ local function send_syslog_data(conf, log_message)
     return res, err_msg
 end
 
+-- remove stale objects from the memory after timer expires
+local function remove_stale_objects(premature)
+    if premature then
+        return
+    end
+
+    for key, batch in ipairs(buffers) do
+        if #batch.entry_buffer.entries == 0 and #batch.batch_to_process == 0 then
+            core.log.debug("removing batch processor stale object, route id:", tostring(key))
+            buffers[key] = nil
+        end
+    end
+
+    stale_timer_running = false
+end
+
 -- log phase in APISIX
 function _M.log(conf)
     local entry = log_util.get_full_log(ngx)
@@ -116,6 +136,12 @@ function _M.log(conf)
 
     local log_buffer = buffers[entry.route_id]
 
+    if not stale_timer_running then
+        -- run the timer every 30 mins if any log is present
+        timer_at(1800, remove_stale_objects)
+        stale_timer_running = true
+    end
+
     if log_buffer then
         log_buffer:push(entry)
         return
diff --git a/apisix/plugins/tcp-logger.lua b/apisix/plugins/tcp-logger.lua
index 424b6933..197f424d 100644
--- a/apisix/plugins/tcp-logger.lua
+++ b/apisix/plugins/tcp-logger.lua
@@ -97,7 +97,7 @@ local function send_tcp_data(conf, log_message)
     return res, err_msg
 end
 
-
+-- remove stale objects from the memory after timer expires
 local function remove_stale_objects(premature)
     if premature then
         return
diff --git a/apisix/plugins/udp-logger.lua b/apisix/plugins/udp-logger.lua
index 957e732f..119d3159 100644
--- a/apisix/plugins/udp-logger.lua
+++ b/apisix/plugins/udp-logger.lua
@@ -80,7 +80,7 @@ local function send_udp_data(conf, log_message)
     return res, err_msg
 end
 
-
+-- remove stale objects from the memory after timer expires
 local function remove_stale_objects(premature)
     if premature then
         return