From 90b729d29d8411f5f93b132c7193adee7750eee0 Mon Sep 17 00:00:00 2001
From: Amnon Heiman <amnon@scylladb.com>
Date: Mon, 19 Dec 2016 13:00:57 +0200
Subject: [PATCH] http: Move metrics registration to the metrics layer

This changes the http metrics registration to use the metrics
registration instead of the collectd.

This is a resubmission of the patch with the updated API.

Message-Id: <1482145257-31726-1-git-send-email-amnon@scylladb.com>
---
 http/httpd.cc | 26 ++++++++------------------
 http/httpd.hh |  4 ++--
 2 files changed, 10 insertions(+), 20 deletions(-)

diff --git a/http/httpd.cc b/http/httpd.cc
index 5d99ace34b8..be9465ba674 100644
--- a/http/httpd.cc
+++ b/http/httpd.cc
@@ -26,7 +26,7 @@
 #include "core/distributed.hh"
 #include "core/queue.hh"
 #include "core/future-util.hh"
-#include "core/scollectd.hh"
+#include "core/metrics.hh"
 #include <iostream>
 #include <algorithm>
 #include <unordered_map>
@@ -41,22 +41,12 @@ using namespace std::chrono_literals;
 
 namespace httpd {
 http_stats::http_stats(http_server& server)
-    : _regs{
-        scollectd::add_polled_metric(
-            scollectd::type_instance_id("httpd", scollectd::per_cpu_plugin_instance,
-                    "connections", "http-connections"),
-            scollectd::make_typed(scollectd::data_type::DERIVE,
-                    [&server] { return server.total_connections(); })),
-        scollectd::add_polled_metric(
-            scollectd::type_instance_id("httpd", scollectd::per_cpu_plugin_instance,
-                    "current_connections", "current"),
-            scollectd::make_typed(scollectd::data_type::GAUGE,
-                    [&server] { return server.current_connections(); })),
-        scollectd::add_polled_metric(
-            scollectd::type_instance_id("httpd", scollectd::per_cpu_plugin_instance,
-                    "http_requests", "served"),
-            scollectd::make_typed(scollectd::data_type::DERIVE,
-                    [&server] { return server.requests_served(); })),
-    } {
+ {
+    namespace sm = seastar::metrics;
+    _metric_groups.add_group("httpd", {
+            sm::make_derive("connections_total", [&server] { return server.total_connections(); }, sm::description("The total number of connections opened")),
+            sm::make_gauge("connections_current", [&server] { return server.current_connections(); }, sm::description("The current number of open  connections")),
+            sm::make_derive("requests_served", [&server] { return server.requests_served(); }, sm::description("The total number of http requests served"))
+    });
 }
 }
diff --git a/http/httpd.hh b/http/httpd.hh
index 92acb2776cd..78954c5637a 100644
--- a/http/httpd.hh
+++ b/http/httpd.hh
@@ -32,7 +32,7 @@
 #include "core/distributed.hh"
 #include "core/queue.hh"
 #include "core/future-util.hh"
-#include "core/scollectd.hh"
+#include "core/metrics_registration.hh"
 #include <iostream>
 #include <algorithm>
 #include <unordered_map>
@@ -53,7 +53,7 @@ class http_stats;
 using namespace std::chrono_literals;
 
 class http_stats {
-    scollectd::registrations _regs;
+    seastar::metrics::metric_groups _metric_groups;
 public:
     http_stats(http_server& server);
 };