fix(prometheus): disable features when plugin is turned off

apisix/plugin.lua

@@ -97,6 +97,29 @@ local function check_disable(plugin_conf)
     return plugin_conf._meta.disable
 end
 
+--- check if the plugin is disabled with metatable
+--- if the plugin_conf is nil, return true
+--- if the plugin_conf._meta is nil, return true (enable default)
+--- if the plugin_conf._meta.disable is nil, return false
+--- true means plugin is disabled, false means plugin is enabled
+local function check_disable_with_metatable(plugin_conf)
+    if not plugin_conf then
+        return true
+    end
+
+    if not plugin_conf._meta then
+        return false
+    end
+
+    if type(plugin_conf._meta) ~= "table" then
+        return true
+    end
+
+    return plugin_conf._meta.disable
+end
+
+_M.check_disable_with_metatable = check_disable_with_metatable
+
 local PLUGIN_TYPE_HTTP = 1
 local PLUGIN_TYPE_STREAM = 2
 local PLUGIN_TYPE_HTTP_WASM = 3

apisix/utils/batch-processor.lua

@@ -15,6 +15,7 @@
 -- limitations under the License.
 --
 local core = require("apisix.core")
+local plugin = require("apisix.plugin")
 local setmetatable = setmetatable
 local timer_at = ngx.timer.at
 local ipairs = ipairs
@@ -184,8 +185,9 @@ function batch_processor:push(entry)
         return
     end
 
-    if prometheus and prometheus.get_prometheus() and not batch_metrics and self.name
-       and self.route_id and self.server_addr then
+    if not plugin.check_disable_with_metatable(plugin.get("prometheus"))
+        and not batch_metrics and self.name
+        and self.route_id and self.server_addr then
         batch_metrics = prometheus.get_prometheus():gauge("batch_process_entries",
                                                           "batch process remaining entries",
                                                           {"name", "route_id", "server_addr"})

t/xrpc/prometheus.t

@@ -271,3 +271,32 @@ passed
 GET /apisix/prometheus/metrics
 --- response_body eval
 qr/apisix_redis_commands_total\{route="1",command="hmset"\} 1/
+
+
+
+=== TEST 9: remove public API route and test route
+--- config
+    location /t {
+        content_by_lua_block {
+            local t = require("lib.test_admin").test
+            local code, body = t('/apisix/admin/routes/1',
+                ngx.HTTP_DELETE
+            )
+            if code >= 300 then
+                ngx.status = code
+            end
+            ngx.say(body)
+        }
+    }
+--- response_body
+passed
+
+
+
+=== TEST 10: fetch the prometheus metric data while prometheus plugin is disabled
+--- yaml_config
+plugins:
+  - limit-count
+--- request
+GET /apisix/prometheus/metrics
+--- error_code: 404