fix: the prometheus lables are inconsistent when using the same batch-processor instance on multi plugins

apisix/utils/batch-processor.lua

@@ -54,6 +54,15 @@ local function schedule_func_exec(self, delay, batch)
 end
 
 
+local function set_metrics(self, count)
+    -- add batch metric for every route
+    if batch_metrics and self.name and self.route_id and self.server_addr then
+        self.label = {self.name, self.route_id, self.server_addr}
+        batch_metrics:set(count, self.label)
+    end
+end
+
+
 function execute_func(premature, self, batch)
     if premature then
         return
@@ -160,11 +169,7 @@ function batch_processor:push(entry)
 
     local entries = self.entry_buffer.entries
     table.insert(entries, entry)
-    -- add batch metric for every route
-    if batch_metrics  then
-        self.label = {self.name, self.route_id, self.server_addr}
-        batch_metrics:set(#entries, self.label)
-    end
+    set_metrics(self, #entries)
 
     if #entries == 1 then
         self.first_entry_t = now()
@@ -190,10 +195,7 @@ function batch_processor:process_buffer()
             "buffercount[", #self.entry_buffer.entries ,"]")
         self.batch_to_process[#self.batch_to_process + 1] = self.entry_buffer
         self.entry_buffer = {entries = {}, retry_count = 0}
-        if batch_metrics then
-            self.label = {self.name, self.route_id, self.server_addr}
-            batch_metrics:set(0, self.label)
-        end
+        set_metrics(self, 0)
     end
 
     for _, batch in ipairs(self.batch_to_process) do

t/plugin/prometheus3.t

@@ -30,6 +30,19 @@ repeat_each(1);
 no_long_string();
 no_shuffle();
 no_root_location();
+
+add_block_preprocessor(sub {
+    my ($block) = @_;
+
+    if (!$block->request) {
+        $block->set_value("request", "GET /t");
+    }
+
+    if ((!defined $block->error_log) && (!defined $block->no_error_log)) {
+        $block->set_value("no_error_log", "[error]");
+    }
+});
+
 run_tests;
 
 __DATA__
@@ -74,12 +87,8 @@ __DATA__
             ngx.say(body)
         }
     }
---- request
-GET /t
 --- response_body
 passed
---- no_error_log
-[error]
 
 
 
@@ -88,5 +97,105 @@ passed
 ["GET /hello", "GET /apisix/prometheus/metrics"]
 --- error_code eval
 [200, 200]
---- no_error_log
-[error]
+
+
+
+=== TEST 3: apisix_batch_process_entries, mess with global rules
+--- config
+    location /t {
+        content_by_lua_block {
+            local t = require("lib.test_admin").test
+            local code, body = t('/apisix/admin/routes/1',
+                 ngx.HTTP_PUT,
+                 [[{
+                        "plugins": {
+                            "prometheus": {}
+                        },
+                        "upstream": {
+                            "nodes": {
+                                "127.0.0.1:1980": 1
+                            },
+                            "type": "roundrobin"
+                        },
+                        "uri": "/batch-process-metrics-aa"
+                }]]
+                )
+            if code >= 300 then
+                ngx.status = code
+                ngx.say(body)
+                return
+            end
+
+            local code, body = t('/apisix/admin/plugin_metadata/error-log-logger',
+                ngx.HTTP_PUT,
+                [[{
+                    "tcp": {
+                        "host": "127.0.0.1",
+                        "port": 1999
+                    },
+                    "max_retry_count": 1000,
+                    "level": "NOTICE"
+                }]]
+                )
+            if code >= 300 then
+                ngx.status = code
+                ngx.say(body)
+                return
+            end
+
+            local code, body = t('/apisix/admin/global_rules/1',
+                 ngx.HTTP_PUT,
+                 [[{
+                        "plugins": {
+                            "http-logger": {
+                                "uri": "http://127.0.0.1:1979"
+                            }
+                        }
+                }]]
+                )
+
+            if code >= 300 then
+                ngx.status = code
+            end
+            ngx.say(body)
+        }
+    }
+--- response_body
+passed
+
+
+
+=== TEST 4: check metrics
+--- yaml_config
+plugins:
+  - error-log-logger
+  - prometheus
+  - http-logger
+--- request
+GET /t
+--- config
+    location /t {
+        content_by_lua_block {
+            local http = require "resty.http"
+            local httpc = http.new()
+            local uri = "http://127.0.0.1:" .. ngx.var.server_port
+                        .. "/batch-process-metrics-aa"
+            local res, err = httpc:request_uri(uri, {method = "GET"})
+            if not res then
+                ngx.say(err)
+                return
+            end
+
+            ngx.sleep(2)
+            local uri = "http://127.0.0.1:" .. ngx.var.server_port
+                        .. "/apisix/prometheus/metrics"
+            local res, err = httpc:request_uri(uri, {method = "GET"})
+            if not res then
+                ngx.say(err)
+                return
+            end
+            ngx.say(res.body)
+        }
+    }
+--- response_body_like eval
+qr/apisix_batch_process_entries\{name="http logger",route_id="1",server_addr="127.0.0.1"\} \d+/