fix(prometheus): add a toggle switch for wasm metrics export

Kong · Dec 2, 2024 · f3dcb8f · f3dcb8f
1 parent 35aa605
commit f3dcb8f
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Showing 5 changed files with 31 additions and 3 deletions.
diff --git a/kong/clustering/compat/removed_fields.lua b/kong/clustering/compat/removed_fields.lua
@@ -228,4 +228,11 @@ return {
       "queue.concurrency_limit",
     },
   },
+
+  -- Any dataplane older than 3.8.0
+  [3009000000] = {
+    prometheus = {
+      "wasm_metrics",
+    },
+  },
 }
diff --git a/kong/plugins/prometheus/exporter.lua b/kong/plugins/prometheus/exporter.lua
@@ -206,7 +206,19 @@ end
 
 
 local function configure(configs)
-  IS_PROMETHEUS_ENABLED = configs ~= nil
+  IS_PROMETHEUS_ENABLED = false
+  wasm.set_enabled(false)
+
+  if configs ~= nil then
+    IS_PROMETHEUS_ENABLED = true
+
+    for i = 1, #configs do
+      if configs[i].wasm_metrics then
+        wasm.set_enabled(true)
+        break
+      end
+    end
+  end
 end
 
 

diff --git a/kong/plugins/prometheus/schema.lua b/kong/plugins/prometheus/schema.lua
@@ -22,6 +22,7 @@ return {
           { latency_metrics = { description = "A boolean value that determines if latency metrics should be collected. If enabled, `kong_latency_ms`, `upstream_latency_ms` and `request_latency_ms` metrics will be exported.", type = "boolean", default = false }, },
           { bandwidth_metrics = { description = "A boolean value that determines if bandwidth metrics should be collected. If enabled, `bandwidth_bytes` and `stream_sessions_total` metrics will be exported.", type = "boolean", default = false }, },
           { upstream_health_metrics = { description = "A boolean value that determines if upstream metrics should be collected. If enabled, `upstream_target_health` metric will be exported.", type = "boolean", default = false }, },
+          { wasm_metrics = { description = "A boolean value that determines if Wasm metrics should be collected.", type = "boolean", default = false }, },
         },
         custom_validator = validate_shared_dict,
     }, },

diff --git a/kong/plugins/prometheus/wasmx.lua b/kong/plugins/prometheus/wasmx.lua
@@ -18,6 +18,7 @@ local _M = {}
 local FLUSH_EVERY = 100
 local GET_METRIC_OPTS = { prefix = false }
 
+local export_enabled = false
 
 local metrics_data_buf = buf_new()
 local labels_serialization_buf = buf_new()
@@ -181,7 +182,7 @@ end
 
 
 _M.metrics_data = function()
-  if not wasm.enabled() then
+  if not export_enabled or not wasm.enabled() then
     return
   end
 
@@ -231,4 +232,8 @@ _M.metrics_data = function()
 end
 
 
+function _M.set_enabled(enabled)
+  export_enabled = enabled
+end
+
 return _M
diff --git a/spec/03-plugins/26-prometheus/09-wasmx_spec.lua b/spec/03-plugins/26-prometheus/09-wasmx_spec.lua
@@ -90,7 +90,10 @@ for _, strategy in helpers.each_strategy() do
       add_filter_to_service(bp, "tests", service)
       add_filter_to_service(bp, "tests", service2)
 
-      bp.plugins:insert({ name = "prometheus" })
+      assert(bp.plugins:insert({
+        name = "prometheus",
+        config = { wasm_metrics = true },
+      }))
 
       assert(helpers.start_kong({
         nginx_conf = "spec/fixtures/custom_nginx.template",