feature(datadog) Add resp-size metric

kong/plugins/datadog/handler.lua

@@ -12,25 +12,28 @@ local string_gsub = string.gsub
 local pairs = pairs
 local NGX_ERR = ngx.ERR
 
-local function request_counter(api_name, logger)
-  local stat = api_name..".request.count"
-  logger:counter(stat, 1, 1)
-end
-
-local function status_counter(api_name, message, logger)
-  local stat = api_name..".request.status."..message.response.status
-  logger:counter(stat, 1, 1)
-end
-
-local function request_size_gauge(api_name, message, logger)
-  local stat = api_name..".request.size"
-  logger:gauge(stat, message.request.size, 1)
-end
-
-local function latency_gauge(api_name, message, logger)
-  local stat = api_name..".latency"
-  logger:gauge(stat, message.latencies.request, 1)
-end
+local gauges = {
+  request_size = function (api_name, message, logger)
+    local stat = api_name..".request.size"
+    logger:gauge(stat, message.request.size, 1)
+  end,
+  response_size = function (api_name, message, logger)
+    local stat = api_name..".response.size"
+    logger:gauge(stat, message.response.size, 1)
+  end,
+  status_count = function (api_name, message, logger)
+    local stat = api_name..".request.status."..message.response.status
+    logger:counter(stat, 1, 1)
+  end,
+  latency = function (api_name, message, logger)
+    local stat = api_name..".latency"
+    logger:gauge(stat, message.latencies.request, 1)
+  end,
+  request_count = function (api_name, message, logger)
+    local stat = api_name..".request.count"
+    logger:counter(stat, 1, 1)
+  end
+}
 
 local function log(premature, conf, message)
   if premature then return end
@@ -43,17 +46,9 @@ local function log(premature, conf, message)
 
   local api_name = string_gsub(message.api.name, "%.", "_")
   for _, metric in pairs(conf.metrics) do
-    if metric == "request_size" then
-      request_size_gauge(api_name, message, logger)
-    end
-    if metric == "status_count" then
-      status_counter(api_name, message, logger)
-    end
-    if metric == "latency" then
-      latency_gauge(api_name, message, logger)
-    end
-    if metric == "request_count" then
-      request_counter(api_name, logger)
+    local gauge = gauges[metric]
+    if gauge ~= nil then
+      gauge(api_name, message, logger)
     end
   end
 

kong/plugins/datadog/schema.lua

@@ -2,7 +2,7 @@ return {
   fields = {
     host = {required = true, type = "string", default = "localhost"},
     port = {required = true, type = "number", default = 8125},
-    metrics = {required = true, type = "array", enum = {"request_count", "latency", "request_size", "status_count"}, default = {"request_count", "latency", "request_size", "status_count"}}, 
+    metrics = {required = true, type = "array", enum = {"request_count", "latency", "request_size", "status_count", "response_size"}, default = {"request_count", "latency", "request_size", "status_count", "response_size"}}, 
     timeout = {type = "number", default = 10000}
   }
 }

spec/plugins/datadog/log_spec.lua

@@ -15,14 +15,16 @@ describe("Datadog Plugin", function()
         {request_host = "logging2.com", upstream_url = "http://mockbin.com"},
         {request_host = "logging3.com", upstream_url = "http://mockbin.com"},
         {request_host = "logging4.com", upstream_url = "http://mockbin.com"},
-        {request_host = "logging5.com", upstream_url = "http://mockbin.com"}
+        {request_host = "logging5.com", upstream_url = "http://mockbin.com"},
+        {request_host = "logging6.com", upstream_url = "http://mockbin.com"},
       },
       plugin = {
         {name = "datadog", config = {host = "127.0.0.1", port = UDP_PORT, metrics = {"request_count"}}, __api = 1},
         {name = "datadog", config = {host = "127.0.0.1", port = UDP_PORT, metrics = {"latency"}}, __api = 2},
         {name = "datadog", config = {host = "127.0.0.1", port = UDP_PORT, metrics = {"status_count"}}, __api = 3},
         {name = "datadog", config = {host = "127.0.0.1", port = UDP_PORT, metrics = {"request_size"}}, __api = 4},
-        {name = "datadog", config = {host = "127.0.0.1", port = UDP_PORT}, __api = 5}
+        {name = "datadog", config = {host = "127.0.0.1", port = UDP_PORT}, __api = 5},
+        {name = "datadog", config = {host = "127.0.0.1", port = UDP_PORT, metrics = {"response_size"}}, __api = 6},
       }
     }
     spec_helper.start_kong()
@@ -56,7 +58,7 @@ describe("Datadog Plugin", function()
     assert.equal("kong.logging3_com.request.status.200:1|c", res)
   end)
 
-  it("#ci should log to UDP when metrics is request_size", function()
+  it("should log to UDP when metrics is request_size", function()
     local thread = spec_helper.start_udp_server(UDP_PORT) -- Starting the mock UDP server
 
     local _, status = http_client.get(STUB_GET_URL, nil, {host = "logging4.com"})
@@ -65,8 +67,11 @@ describe("Datadog Plugin", function()
     local ok, res = thread:join()
     assert.True(ok)
     assert.truthy(res)
-    -- 113 locally but 111 on travis
-    assert.equal("kong.logging4_com.request.size:113|g", res)
+    local message = {}
+    for w in string.gmatch(res,"kong.logging4_com.request.size:%d*|g") do
+      table.insert(message, w)
+    end
+    assert.equal(1, #message)
   end)
 
   it("should log to UDP when metrics is latency", function()
@@ -98,4 +103,20 @@ describe("Datadog Plugin", function()
     assert.truthy(res)
     assert.equal("kong.logging5_com.request.count:1|c", res)
   end)
+
+  it("should log to UDP when metrics is response_size", function()
+    local thread = spec_helper.start_udp_server(UDP_PORT) -- Starting the mock UDP server
+
+    local _, status = http_client.get(STUB_GET_URL, nil, {host = "logging6.com"})
+    assert.equal(200, status)
+
+    local ok, res = thread:join()
+    assert.True(ok)
+    assert.truthy(res)
+    local message = {}
+    for w in string.gmatch(res,"kong.logging6_com.response.size:%d*|g") do
+      table.insert(message, w)
+    end
+    assert.equal(1, #message)
+  end)
 end)