fix(datadog): fix a bug that datalog plugin is not triggered for serv…

…iceless routes (#12068)

fix a bug that datadog plugin is not triggered for serviceless routes.

In this PR, the datadog plugin can be triggered even if the serviceless routes are hit, and the value of tag name for the metric data is set to an empty string which is still a valid tag for datadog.


FTI-5576

changelog/unreleased/kong/serviceless-routes-still-trigger-datalog-plugin.yml

@@ -0,0 +1,3 @@
+message: "**Datadog**: Fix a bug that datadog plugin is not triggered for serviceless routes. In this fix, datadog plugin is always triggered, and the value of tag `name`(service_name) is set as an empty value."
+type: bugfix
+scope: Plugin

kong/plugins/datadog/handler.lua

@@ -56,10 +56,6 @@ local function send_entries_to_datadog(conf, messages)
   end
 
   for _, message in ipairs(messages) do
-    local name = gsub(message.service.name ~= null and
-                      message.service.name or message.service.host,
-                      "%.", "_")
-
     local stat_name  = {
       request_size     = "request.size",
       response_size    = "response.size",
@@ -87,8 +83,10 @@ local function send_entries_to_datadog(conf, messages)
       local get_consumer_id = get_consumer_id[metric_config.consumer_identifier]
       local consumer_id     = get_consumer_id and get_consumer_id(message.consumer) or nil
       local tags            = compose_tags(
-              name, message.response and message.response.status or "-",
-              consumer_id, metric_config.tags, conf)
+                                message.service and gsub(message.service.name ~= null and
+                                message.service.name or message.service.host, "%.", "_") or "",
+                                message.response and message.response.status or "-",
+                                consumer_id, metric_config.tags, conf)
 
       logger:send_statsd(stat_name, stat_value,
                          logger.stat_types[metric_config.stat_type],
@@ -107,12 +105,7 @@ local DatadogHandler = {
   VERSION = kong_meta.version,
 }
 
-
 function DatadogHandler:log(conf)
-  if not ngx.ctx.service then
-    return
-  end
-
   local ok, err = Queue.enqueue(
     Queue.get_plugin_params("datadog", conf),
     send_entries_to_datadog,

spec/03-plugins/08-datadog/01-log_spec.lua

@@ -1,8 +1,10 @@
 local helpers = require "spec.helpers"
 local cjson = require "cjson"
+local stringx = require "pl.stringx"
 
 
 describe("Plugin: datadog (log)", function()
+  local DEFAULT_METRICS_COUNT = 6
 
   lazy_setup(function()
     helpers.setenv('KONG_DATADOG_AGENT_HOST', 'localhost')
@@ -93,6 +95,11 @@ describe("Plugin: datadog (log)", function()
           }
         }
 
+        local route9 = bp.routes:insert {
+          paths = { "/serviceless" },
+          no_service = true,
+        }
+
         bp.plugins:insert {
           name     = "key-auth",
           route = { id = route1.id },
@@ -237,6 +244,25 @@ describe("Plugin: datadog (log)", function()
           },
         }
 
+        bp.plugins:insert {
+          name     = "datadog",
+          route    = { id = route9.id },
+          config   = {
+            host             = "127.0.0.1",
+            port             = 9999,
+            queue_size       = 2,
+          },
+        }
+
+        bp.plugins:insert {
+          name     = "request-termination",
+          route    = { id = route9.id },
+          config   = {
+            status_code = 200,
+            message     = "OK",
+          }
+        }
+
         assert(helpers.start_kong({
           database   = strategy,
           nginx_conf = "spec/fixtures/custom_nginx.template",
@@ -245,17 +271,23 @@ describe("Plugin: datadog (log)", function()
 
         proxy_client = helpers.proxy_client()
       end)
+
       lazy_teardown(function()
+        helpers.stop_kong()
+      end)
+
+      before_each(function()
+        proxy_client = helpers.proxy_client()
+      end)
+
+      after_each(function()
         if proxy_client then
           proxy_client:close()
         end
-
-
-        helpers.stop_kong()
       end)
 
       it("logs metrics over UDP", function()
-        local thread = helpers.udp_server(9999, 6)
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT)
 
         local res = assert(proxy_client:send {
           method  = "GET",
@@ -268,7 +300,7 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
         assert.contains("kong.request.count:1|c|#name:dd1,status:200,consumer:bar,app:kong" , gauges)
         assert.contains("kong.latency:%d+|ms|#name:dd1,status:200,consumer:bar,app:kong", gauges, true)
         assert.contains("kong.request.size:%d+|ms|#name:dd1,status:200,consumer:bar,app:kong", gauges, true)
@@ -278,7 +310,7 @@ describe("Plugin: datadog (log)", function()
       end)
 
       it("logs metrics over UDP #grpc", function()
-        local thread = helpers.udp_server(9999, 6)
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT)
 
         local grpc_cleint = assert(helpers.proxy_client_grpc())
 
@@ -293,7 +325,7 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
         assert.contains("kong.request.count:1|c|#name:grpc,status:200,consumer:bar,app:kong" , gauges)
         assert.contains("kong.latency:%d+|ms|#name:grpc,status:200,consumer:bar,app:kong", gauges, true)
         assert.contains("kong.request.size:%d+|ms|#name:grpc,status:200,consumer:bar,app:kong", gauges, true)
@@ -303,7 +335,7 @@ describe("Plugin: datadog (log)", function()
       end)
 
       it("logs metrics over UDP with custom prefix", function()
-        local thread = helpers.udp_server(9999, 6)
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT)
 
         local res = assert(proxy_client:send {
           method  = "GET",
@@ -316,7 +348,7 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
         assert.contains("prefix.request.count:1|c|#name:dd4,status:200,consumer:bar,app:kong",gauges)
         assert.contains("prefix.latency:%d+|ms|#name:dd4,status:200,consumer:bar,app:kong", gauges, true)
         assert.contains("prefix.request.size:%d+|ms|#name:dd4,status:200,consumer:bar,app:kong", gauges, true)
@@ -326,7 +358,7 @@ describe("Plugin: datadog (log)", function()
       end)
 
       it("logs metrics over UDP with custom tag names", function()
-        local thread = helpers.udp_server(9999, 6)
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT)
 
         local res = assert(proxy_client:send {
           method  = "GET",
@@ -339,7 +371,7 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
         assert.contains("kong.request.count:1|c|#upstream:dd6,http_status:200,user:bar,app:kong",gauges)
         assert.contains("kong.latency:%d+|ms|#upstream:dd6,http_status:200,user:bar,app:kong", gauges, true)
         assert.contains("kong.request.size:%d+|ms|#upstream:dd6,http_status:200,user:bar,app:kong", gauges, true)
@@ -387,7 +419,7 @@ describe("Plugin: datadog (log)", function()
       end)
 
       it("logs metrics to host/port defined via environment variables", function()
-        local thread = helpers.udp_server(9999, 6)
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT)
 
         local res = assert(proxy_client:send {
           method  = "GET",
@@ -400,7 +432,7 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
         assert.contains("kong.request.count:1|c|#name:dd5,status:200,consumer:bar,app:kong" , gauges)
         assert.contains("kong.latency:%d+|ms|#name:dd5,status:200,consumer:bar,app:kong", gauges, true)
         assert.contains("kong.request.size:%d+|ms|#name:dd5,status:200,consumer:bar,app:kong", gauges, true)
@@ -410,7 +442,7 @@ describe("Plugin: datadog (log)", function()
       end)
 
       it("logs metrics in several batches", function()
-        local thread = helpers.udp_server(9999, 6)
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT)
 
         local res = assert(proxy_client:send {
           method  = "GET",
@@ -423,7 +455,7 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
         assert.contains("kong.request.count:1|c|#name:dd7,status:200,consumer:bar,app:kong" , gauges)
         assert.contains("kong.latency:%d+|ms|#name:dd7,status:200,consumer:bar,app:kong", gauges, true)
         assert.contains("kong.request.size:%d+|ms|#name:dd7,status:200,consumer:bar,app:kong", gauges, true)
@@ -448,7 +480,7 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
       end)
 
       it("should not return a runtime error (regression)", function()
@@ -476,9 +508,9 @@ describe("Plugin: datadog (log)", function()
 
         thread:join()
       end)
-      
+
       it("referenceable fields works", function()
-        local thread = helpers.udp_server(9999, 6, 6)
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT, 6)
         local another_proxy_client = helpers.proxy_client()
 
         local res = assert(another_proxy_client:send {
@@ -493,7 +525,32 @@ describe("Plugin: datadog (log)", function()
 
         local ok, gauges = thread:join()
         assert.True(ok)
-        assert.equal(6, #gauges)
+        assert.equal(DEFAULT_METRICS_COUNT, #gauges)
+      end)
+
+      it("datadog plugin is triggered for serviceless routes", function()
+        local thread = helpers.udp_server(9999, DEFAULT_METRICS_COUNT)
+        local res = assert(proxy_client:send {
+          method  = "GET",
+          path    = "/serviceless",
+        })
+
+        local body = assert.res_status(200, res)
+        assert.equals(body, '{"message":"OK"}')
+
+        local ok, gauges = thread:join()
+        assert.True(ok)
+        assert.equals(DEFAULT_METRICS_COUNT, #gauges)
+
+        for _, g in ipairs(gauges) do
+          -- tags start with `#`
+          local tmp = stringx.split(g, '#')
+          local tag_idx = #tmp
+          assert(tag_idx == 2, "Error: missing tags")
+          local tags = tmp[tag_idx]
+          assert(tags, "Error: missing tags")
+          assert(string.match(tags, "name:,"), "Error: the value of `name` must be an empty string for serviceless routes")
+        end
       end)
     end)
   end