From d7226fcc454a96b664a7f567b4bf04338ac7ccf2 Mon Sep 17 00:00:00 2001
From: Avan Thakkar <athakkar@redhat.com>
Date: Mon, 1 Aug 2022 12:20:53 +0530
Subject: [PATCH] exporter: per node metric exporter

Fixes: https://tracker.ceph.com/issues/55046

Signed-off-by: Pere Diaz Bou <pdiazbou@redhat.com>
Signed-off-by: Avan Thakkar <athakkar@redhat.com>
---
 ceph.spec.in                             |  12 +
 src/CMakeLists.txt                       |   3 +
 src/common/options/CMakeLists.txt        |   1 +
 src/common/options/build_options.cc      |   2 +
 src/common/options/ceph-exporter.yaml.in |  54 ++++
 src/common/subsys.h                      |   1 +
 src/exporter/CMakeLists.txt              |  10 +
 src/exporter/DaemonMetricCollector.cc    | 391 +++++++++++++++++++++++
 src/exporter/DaemonMetricCollector.h     | 104 ++++++
 src/exporter/ceph_exporter.cc            |  65 ++++
 src/exporter/http_server.cc              | 169 ++++++++++
 src/exporter/http_server.h               |   5 +
 src/exporter/util.cc                     |  48 +++
 src/exporter/util.h                      |  22 ++
 14 files changed, 887 insertions(+)
 create mode 100644 src/common/options/ceph-exporter.yaml.in
 create mode 100644 src/exporter/CMakeLists.txt
 create mode 100644 src/exporter/DaemonMetricCollector.cc
 create mode 100644 src/exporter/DaemonMetricCollector.h
 create mode 100644 src/exporter/ceph_exporter.cc
 create mode 100644 src/exporter/http_server.cc
 create mode 100644 src/exporter/http_server.h
 create mode 100644 src/exporter/util.cc
 create mode 100644 src/exporter/util.h

diff --git a/ceph.spec.in b/ceph.spec.in
index 136b033b267..ff92857b5e8 100644
--- a/ceph.spec.in
+++ b/ceph.spec.in
@@ -736,6 +736,15 @@ Requires:	libcephfs2 = %{_epoch_prefix}%{version}-%{release}
 %description -n cephfs-mirror
 Daemon for mirroring CephFS snapshots between Ceph clusters.
 
+%package -n ceph-exporter
+Summary: Daemon for exposing perf counters as Prometheus metrics
+%if 0%{?suse_version}
+Group:		System/Filesystems
+%endif
+Requires:	ceph-base = %{_epoch_prefix}%{version}-%{release}
+%description -n ceph-exporter
+Daemon for exposing perf counters as Prometheus metrics
+
 %package -n rbd-fuse
 Summary:	Ceph fuse-based client
 %if 0%{?suse_version}
@@ -1998,6 +2007,9 @@ if [ $1 -ge 1 ] ; then
   fi
 fi
 
+%files -n ceph-exporter
+%{_bindir}/ceph-exporter
+
 %files -n rbd-fuse
 %{_bindir}/rbd-fuse
 %{_mandir}/man8/rbd-fuse.8*
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 807386fa6d9..723ed439fd2 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -606,6 +606,7 @@ endif(NOT WITH_SYSTEM_ROCKSDB)
 
 if(WITH_MGR)
   add_subdirectory(mgr)
+  add_subdirectory(exporter)
 endif()
 
 set(librados_config_srcs
@@ -903,6 +904,7 @@ add_custom_target(vstart-base DEPENDS
     ceph-mon
     ceph-authtool
     ceph-conf
+    ceph-exporter
     monmaptool
     crushtool
     rados)
@@ -915,6 +917,7 @@ endif()
 
 if (WITH_MGR)
   add_dependencies(vstart-base ceph-mgr)
+  add_dependencies(vstart-base ceph-exporter)
 endif()
 
 add_custom_target(vstart DEPENDS vstart-base)
diff --git a/src/common/options/CMakeLists.txt b/src/common/options/CMakeLists.txt
index d2104a0dad2..da24c673f6b 100644
--- a/src/common/options/CMakeLists.txt
+++ b/src/common/options/CMakeLists.txt
@@ -93,6 +93,7 @@ add_options(osd)
 add_options(rbd)
 add_options(rbd-mirror)
 add_options(immutable-object-cache)
+add_options(ceph-exporter)
 
 # if set to empty string, system default luarocks package location (if exist) will be used
 set(rgw_luarocks_location "")
diff --git a/src/common/options/build_options.cc b/src/common/options/build_options.cc
index 001fac90287..867fc2efd7e 100644
--- a/src/common/options/build_options.cc
+++ b/src/common/options/build_options.cc
@@ -18,6 +18,7 @@ std::vector<Option> get_immutable_object_cache_options();
 std::vector<Option> get_mds_options();
 std::vector<Option> get_mds_client_options();
 std::vector<Option> get_cephfs_mirror_options();
+std::vector<Option> get_ceph_exporter_options();
 
 std::vector<Option> build_options()
 {
@@ -46,6 +47,7 @@ std::vector<Option> build_options()
   ingest(get_mds_options(), "mds");
   ingest(get_mds_client_options(), "mds_client");
   ingest(get_cephfs_mirror_options(), "cephfs-mirror");
+  ingest(get_ceph_exporter_options(), "ceph-exporter");
 
   return result;
 }
diff --git a/src/common/options/ceph-exporter.yaml.in b/src/common/options/ceph-exporter.yaml.in
new file mode 100644
index 00000000000..798a185e96b
--- /dev/null
+++ b/src/common/options/ceph-exporter.yaml.in
@@ -0,0 +1,54 @@
+# -*- mode: YAML -*-
+---
+
+options:
+- name: exporter_sock_dir
+  type: str
+  level: advanced
+  desc: The path to ceph daemons socket files dir
+  default: /var/run/ceph/
+  services:
+  - ceph-exporter
+  flags:
+  - runtime
+- name: exporter_addr
+  type: str
+  level: advanced
+  desc: Host ip address where exporter is deployed
+  default: 0.0.0.0
+  services:
+  - ceph-exporter
+- name: exporter_http_port
+  type: int
+  level: advanced
+  desc: Port to deploy exporter on. Default is 9926
+  default: 9926
+  services:
+  - ceph-exporter
+- name: exporter_prio_limit
+  type: int
+  level: advanced
+  desc: Only perf counters greater than or equal to exporter_prio_limit are fetched
+  default: 5
+  services:
+  - ceph-exporter
+  flags:
+  - runtime
+- name: exporter_stats_period
+  type: int
+  level: advanced
+  desc: Time to wait before sending requests again to exporter server (seconds)
+  default: 5
+  services:
+  - ceph-exporter
+  flags:
+  - runtime
+- name: exporter_sort_metrics
+  type: bool
+  level: advanced
+  desc: If true it will sort the metrics and group them.
+  default: true
+  services:
+  - ceph-exporter
+  flags:
+  - runtime
diff --git a/src/common/subsys.h b/src/common/subsys.h
index 4afedb52300..431ec300d9b 100644
--- a/src/common/subsys.h
+++ b/src/common/subsys.h
@@ -98,3 +98,4 @@ SUBSYS(seastore_backref, 0, 5)
 SUBSYS(alienstore, 0, 5)
 SUBSYS(mclock, 1, 5)
 SUBSYS(cyanstore, 0, 5)
+SUBSYS(ceph_exporter, 1, 5)
diff --git a/src/exporter/CMakeLists.txt b/src/exporter/CMakeLists.txt
new file mode 100644
index 00000000000..0c0c03bf91d
--- /dev/null
+++ b/src/exporter/CMakeLists.txt
@@ -0,0 +1,10 @@
+set(exporter_srcs
+  ceph_exporter.cc
+  DaemonMetricCollector.cc
+  http_server.cc
+  util.cc
+  )
+add_executable(ceph-exporter ${exporter_srcs})
+target_link_libraries(ceph-exporter
+  global-static ceph-common)
+install(TARGETS ceph-exporter DESTINATION bin)
diff --git a/src/exporter/DaemonMetricCollector.cc b/src/exporter/DaemonMetricCollector.cc
new file mode 100644
index 00000000000..7f88113b990
--- /dev/null
+++ b/src/exporter/DaemonMetricCollector.cc
@@ -0,0 +1,391 @@
+#include "DaemonMetricCollector.h"
+#include "common/admin_socket_client.h"
+#include "common/debug.h"
+#include "common/hostname.h"
+#include "common/perf_counters.h"
+#include "global/global_init.h"
+#include "global/global_context.h"
+#include "common/split.h"
+#include "include/common_fwd.h"
+#include "util.h"
+
+#include <boost/json/src.hpp>
+#include <chrono>
+#include <filesystem>
+#include <iostream>
+#include <map>
+#include <memory>
+#include <regex>
+#include <string>
+#include <utility>
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_ceph_exporter
+
+using json_object = boost::json::object;
+using json_value = boost::json::value;
+using json_array = boost::json::array;
+
+void DaemonMetricCollector::request_loop(boost::asio::steady_timer &timer) {
+  timer.async_wait([&](const boost::system::error_code &e) {
+    std::cerr << e << std::endl;
+    update_sockets();
+    dump_asok_metrics();
+    auto stats_period = g_conf().get_val<int64_t>("exporter_stats_period");
+    // time to wait before sending requests again
+    timer.expires_from_now(std::chrono::seconds(stats_period));
+    request_loop(timer);
+  });
+}
+
+void DaemonMetricCollector::main() {
+  // time to wait before sending requests again
+
+  boost::asio::io_service io;
+  boost::asio::steady_timer timer{io, std::chrono::seconds(0)};
+  request_loop(timer);
+  io.run();
+}
+
+std::string DaemonMetricCollector::get_metrics() {
+  const std::lock_guard<std::mutex> lock(metrics_mutex);
+  return metrics;
+}
+
+template <class T>
+void add_metric(std::unique_ptr<MetricsBuilder> &builder, T value,
+                std::string name, std::string description, std::string mtype,
+                labels_t labels) {
+  builder->add(std::to_string(value), name, description, mtype, labels);
+}
+
+void add_double_or_int_metric(std::unique_ptr<MetricsBuilder> &builder,
+                              json_value value, std::string name,
+                              std::string description, std::string mtype,
+                              labels_t labels) {
+  if (value.is_int64()) {
+    int64_t v = value.as_int64();
+    add_metric(builder, v, name, description, mtype, labels);
+  } else if (value.is_double()) {
+    double v = value.as_double();
+    add_metric(builder, v, name, description, mtype, labels);
+  }
+}
+
+std::string boost_string_to_std(boost::json::string js) {
+  std::string res(js.data());
+  return res;
+}
+
+std::string quote(std::string value) { return "\"" + value + "\""; }
+
+bool is_hyphen(char ch) { return ch == '-'; }
+
+void DaemonMetricCollector::dump_asok_metrics() {
+  BlockTimer timer(__FILE__, __FUNCTION__);
+
+  std::vector<std::pair<std::string, int>> daemon_pids;
+
+  bool sort = g_conf().get_val<bool>("exporter_sort_metrics");
+  if (sort) {
+    builder = std::unique_ptr<OrderedMetricsBuilder>(new OrderedMetricsBuilder());
+  } else {
+    builder = std::unique_ptr<UnorderedMetricsBuilder>(new UnorderedMetricsBuilder());
+  }
+  for (auto &[daemon_name, sock_client] : clients) {
+    bool ok;
+    sock_client.ping(&ok);
+    if (!ok) {
+      continue;
+    }
+    std::string perf_dump_response = asok_request(sock_client, "perf dump", daemon_name);
+    if (perf_dump_response.size() == 0) {
+      continue;
+    }
+    std::string perf_schema_response = asok_request(sock_client, "perf schema", daemon_name);
+    if (perf_schema_response.size() == 0) {
+      continue;
+    }
+    std::string config_show = asok_request(sock_client, "config show", daemon_name);
+    json_object pid_file_json = boost::json::parse(config_show).as_object();
+    std::string pid_path =
+      boost_string_to_std(pid_file_json["pid_file"].as_string());
+    std::string pid_str = read_file_to_string(pid_path);
+    if (!pid_path.size()) {
+      continue;
+    }
+    daemon_pids.push_back({daemon_name, std::stoi(pid_str)});
+    json_object dump = boost::json::parse(perf_dump_response).as_object();
+    json_object schema = boost::json::parse(perf_schema_response).as_object();
+    for (auto &perf : schema) {
+      auto sv = perf.key();
+      std::string perf_group = {sv.begin(), sv.end()};
+      json_object perf_group_object = perf.value().as_object();
+      for (auto &perf_counter : perf_group_object) {
+        auto sv1 = perf_counter.key();
+        std::string perf_name = {sv1.begin(), sv1.end()};
+        json_object perf_info = perf_counter.value().as_object();
+        auto prio_limit = g_conf().get_val<int64_t>("exporter_prio_limit");
+        if (perf_info["priority"].as_int64() <
+            prio_limit) {
+          continue;
+        }
+        std::string name = "ceph_" + perf_group + "_" + perf_name;
+        std::replace_if(name.begin(), name.end(), is_hyphen, '_');
+
+        // FIXME: test this, based on mgr_module perfpath_to_path_labels
+        auto labels_and_name = get_labels_and_metric_name(daemon_name, name);
+        labels_t labels = labels_and_name.first;
+        name = labels_and_name.second;
+
+        json_value perf_values = dump[perf_group].as_object()[perf_name];
+        dump_asok_metric(perf_info, perf_values, name, labels);
+      }
+    }
+  }
+  dout(10) << "Perf counters retrieved for " << clients.size() << " daemons." << dendl;
+  // get time spent on this function
+  timer.stop();
+  std::string scrap_desc("Time spent scraping and transforming perfcounters to metrics");
+  labels_t scrap_labels;
+  scrap_labels["host"] = quote(ceph_get_hostname());
+  scrap_labels["function"] = quote(__FUNCTION__);
+  add_metric(builder, timer.get_ms(), "ceph_exporter_scrape_time", scrap_desc,
+             "gauge", scrap_labels);
+
+  const std::lock_guard<std::mutex> lock(metrics_mutex);
+  get_process_metrics(daemon_pids);
+  metrics = builder->dump();
+}
+
+std::vector<std::string> read_proc_stat_file(std::string path) {
+  std::string stat = read_file_to_string(path);
+  std::vector<std::string> strings;
+  auto parts = ceph::split(stat);
+  strings.assign(parts.begin(), parts.end());
+  return strings;
+}
+
+struct pstat read_pid_stat(int pid) {
+  std::string stat_path("/proc/" + std::to_string(pid) + "/stat");
+  std::vector<std::string> stats = read_proc_stat_file(stat_path);
+  struct pstat stat;
+  stat.minflt = std::stoul(stats[9]);
+  stat.majflt = std::stoul(stats[11]);
+  stat.utime = std::stoul(stats[13]);
+  stat.stime = std::stoul(stats[14]);
+  stat.num_threads = std::stoul(stats[19]);
+  stat.start_time = std::stoul(stats[21]);
+  stat.vm_size = std::stoul(stats[22]);
+  stat.resident_size = std::stoi(stats[23]);
+  return stat;
+}
+
+void DaemonMetricCollector::get_process_metrics(std::vector<std::pair<std::string, int>> daemon_pids) {
+  std::string path("/proc");
+  std::stringstream ss;
+  for (auto &[daemon_name, pid] : daemon_pids) {
+    std::vector<std::string> uptimes = read_proc_stat_file("/proc/uptime");
+    struct pstat stat = read_pid_stat(pid);
+    int clk_tck = sysconf(_SC_CLK_TCK);
+    double start_time_seconds = stat.start_time / (double)clk_tck;
+    double user_time = stat.utime / (double)clk_tck;
+    double kernel_time = stat.stime / (double)clk_tck;
+    double total_time_seconds = user_time + kernel_time;
+    double uptime = std::stod(uptimes[0]);
+    double elapsed_time = uptime - start_time_seconds;
+    double idle_time = elapsed_time  - total_time_seconds;
+    double usage = total_time_seconds * 100 / elapsed_time;
+
+    labels_t labels;
+    labels["ceph_daemon"] = quote(daemon_name);
+    add_metric(builder, stat.minflt, "ceph_exporter_minflt_total",
+               "Number of minor page faults of daemon", "counter", labels);
+    add_metric(builder, stat.majflt, "ceph_exporter_majflt_total",
+               "Number of major page faults of daemon", "counter", labels);
+    add_metric(builder, stat.num_threads, "ceph_exporter_num_threads",
+               "Number of threads used by daemon", "gauge", labels);
+    add_metric(builder, usage, "ceph_exporter_cpu_usage", "CPU usage of a daemon",
+               "gauge", labels);
+
+    std::string cpu_time_desc = "Process time in kernel/user/idle mode";
+    labels_t cpu_total_labels;
+    cpu_total_labels["ceph_daemon"] = quote(daemon_name);
+    cpu_total_labels["mode"] = quote("kernel");
+    add_metric(builder, kernel_time, "ceph_exporter_cpu_total", cpu_time_desc,
+               "counter", cpu_total_labels);
+    cpu_total_labels["mode"] = quote("user");
+    add_metric(builder, user_time, "ceph_exporter_cpu_total", cpu_time_desc,
+               "counter", cpu_total_labels);
+    cpu_total_labels["mode"] = quote("idle");
+    add_metric(builder, idle_time, "ceph_exporter_cpu_total", cpu_time_desc,
+               "counter", cpu_total_labels);
+    add_metric(builder, stat.vm_size, "ceph_exporter_vm_size", "Virtual memory used in a daemon",
+               "gauge", labels);
+    add_metric(builder, stat.resident_size, "ceph_exporter_resident_size",
+               "Resident memory in a daemon", "gauge", labels);
+  }
+}
+
+std::string DaemonMetricCollector::asok_request(AdminSocketClient &asok,
+                                                std::string command, std::string daemon_name) {
+  std::string request("{\"prefix\": \"" + command + "\"}");
+  std::string response;
+  std::string err = asok.do_request(request, &response);
+  if (err.length() > 0 || response.substr(0, 5) == "ERROR") {
+    dout(1) << "command " << command << "failed for daemon " << daemon_name 
+      << "with error: " << err << dendl;
+    return "";
+  }
+  return response;
+}
+
+std::pair<labels_t, std::string>
+DaemonMetricCollector::get_labels_and_metric_name(std::string daemon_name,
+                                                  std::string metric_name) {
+  std::string new_metric_name;
+  labels_t labels;
+  new_metric_name = metric_name;
+  if (daemon_name.find("rgw") != std::string::npos) {
+    std::string tmp = daemon_name.substr(16, std::string::npos);
+    std::string::size_type pos = tmp.find('.');
+    labels["instance_id"] = quote("rgw." + tmp.substr(0, pos));
+  } else {
+    labels["ceph_daemon"] = quote(daemon_name);
+    if (daemon_name.find("rbd-mirror") != std::string::npos) {
+      std::regex re("^rbd_mirror_image_([^/]+)/(?:(?:([^/]+)/"
+                    ")?)(.*)\\.(replay(?:_bytes|_latency)?)$");
+      std::smatch match;
+      if (std::regex_search(daemon_name, match, re) == true) {
+        new_metric_name = "ceph_rbd_mirror_image_" + match.str(4);
+        labels["pool"] = quote(match.str(1));
+        labels["namespace"] = quote(match.str(2));
+        labels["image"] = quote(match.str(3));
+      }
+    }
+  }
+  return {labels, new_metric_name};
+}
+
+/*
+perf_values can be either a int/double or a json_object. Since
+   json_value is a wrapper of both we use that class.
+ */
+void DaemonMetricCollector::dump_asok_metric(json_object perf_info,
+                                             json_value perf_values,
+                                             std::string name,
+                                             labels_t labels) {
+  int64_t type = perf_info["type"].as_int64();
+  std::string metric_type =
+    boost_string_to_std(perf_info["metric_type"].as_string());
+  std::string description =
+    boost_string_to_std(perf_info["description"].as_string());
+
+  if (type & PERFCOUNTER_LONGRUNAVG) {
+    int64_t count = perf_values.as_object()["avgcount"].as_int64();
+    add_metric(builder, count, name + "_count", description, metric_type,
+               labels);
+    json_value sum_value = perf_values.as_object()["sum"];
+    add_double_or_int_metric(builder, sum_value, name + "_sum", description,
+                             metric_type, labels);
+  } else if (type & PERFCOUNTER_TIME) {
+    if (perf_values.is_int64()) {
+      double value = perf_values.as_int64() / 1000000000.0f;
+      add_metric(builder, value, name, description, metric_type, labels);
+    } else if (perf_values.is_double()) {
+      double value = perf_values.as_double() / 1000000000.0f;
+      add_metric(builder, value, name, description, metric_type, labels);
+    }
+  } else {
+    add_double_or_int_metric(builder, perf_values, name, description,
+                             metric_type, labels);
+  }
+}
+
+void DaemonMetricCollector::update_sockets() {
+  std::string sock_dir = g_conf().get_val<std::string>("exporter_sock_dir");
+  clients.clear();
+  std::filesystem::path sock_path = sock_dir;
+  if(!std::filesystem::is_directory(sock_path.parent_path())) {
+    dout(1) << "ERROR: No such directory exist" << sock_dir << dendl;
+    return;
+  }
+  for (const auto &entry :
+         std::filesystem::directory_iterator(sock_dir)) {
+    if (entry.path().extension() == ".asok") {
+      std::string daemon_socket_name = entry.path().filename().string();
+      std::string daemon_name =
+        daemon_socket_name.substr(0, daemon_socket_name.size() - 5);
+      if (clients.find(daemon_name) == clients.end() &&
+          !(daemon_name.find("mgr") != std::string::npos) &&
+          !(daemon_name.find("ceph-exporter") != std::string::npos)) {
+        AdminSocketClient sock(entry.path().string());
+        clients.insert({daemon_name, std::move(sock)});
+      }
+    }
+  }
+}
+
+void OrderedMetricsBuilder::add(std::string value, std::string name,
+                                std::string description, std::string mtype,
+                                labels_t labels) {
+
+  if (metrics.find(name) == metrics.end()) {
+    Metric metric(name, mtype, description);
+    metrics[name] = std::move(metric);
+  }
+  Metric &metric = metrics[name];
+  metric.add(labels, value);
+}
+
+std::string OrderedMetricsBuilder::dump() {
+  for (auto &[name, metric] : metrics) {
+    out += metric.dump() + "\n";
+  }
+  return out;
+}
+
+void UnorderedMetricsBuilder::add(std::string value, std::string name,
+                                  std::string description, std::string mtype,
+                                  labels_t labels) {
+
+  Metric metric(name, mtype, description);
+  metric.add(labels, value);
+  out += metric.dump() + "\n\n";
+}
+
+std::string UnorderedMetricsBuilder::dump() { return out; }
+
+void Metric::add(labels_t labels, std::string value) {
+  metric_entry entry;
+  entry.labels = labels;
+  entry.value = value;
+  entries.push_back(entry);
+}
+
+std::string Metric::dump() {
+  std::stringstream metric_ss;
+  metric_ss << "# HELP " << name << " " << description << "\n";
+  metric_ss << "# TYPE " << name << " " << mtype << "\n";
+  for (auto &entry : entries) {
+    std::stringstream labels_ss;
+    size_t i = 0;
+    for (auto &[label_name, label_value] : entry.labels) {
+      labels_ss << label_name << "=" << label_value;
+      if (i < entry.labels.size() - 1) {
+        labels_ss << ",";
+      }
+      i++;
+    }
+    metric_ss << name << "{" << labels_ss.str() << "} " << entry.value;
+    if (&entry != &entries.back()) {
+      metric_ss << "\n";
+    }
+  }
+  return metric_ss.str();
+}
+
+DaemonMetricCollector &collector_instance() {
+  static DaemonMetricCollector instance;
+  return instance;
+}
diff --git a/src/exporter/DaemonMetricCollector.h b/src/exporter/DaemonMetricCollector.h
new file mode 100644
index 00000000000..c8238669c41
--- /dev/null
+++ b/src/exporter/DaemonMetricCollector.h
@@ -0,0 +1,104 @@
+#pragma once
+
+#include "common/admin_socket_client.h"
+#include <map>
+#include <string>
+#include <vector>
+
+#include <boost/asio.hpp>
+#include <boost/json/object.hpp>
+#include <filesystem>
+#include <map>
+#include <string>
+#include <vector>
+
+struct pstat {
+  unsigned long utime;
+  unsigned long stime;
+  unsigned long minflt;
+  unsigned long majflt;
+  unsigned long start_time;
+  int num_threads;
+  unsigned long vm_size;
+  int resident_size;
+};
+
+class MetricsBuilder;
+class OrderedMetricsBuilder;
+class UnorderedMetricsBuilder;
+class Metric;
+
+typedef std::map<std::string, std::string> labels_t;
+
+class DaemonMetricCollector {
+public:
+  void main();
+  std::string get_metrics();
+
+private:
+  std::map<std::string, AdminSocketClient> clients;
+  std::string metrics;
+  std::mutex metrics_mutex;
+  std::unique_ptr<MetricsBuilder> builder;
+  void update_sockets();
+  void request_loop(boost::asio::steady_timer &timer);
+
+  void dump_asok_metrics();
+  void dump_asok_metric(boost::json::object perf_info,
+                        boost::json::value perf_values, std::string name,
+                        labels_t labels);
+  std::pair<labels_t, std::string>
+  get_labels_and_metric_name(std::string daemon_name, std::string metric_name);
+  void get_process_metrics(std::vector<std::pair<std::string, int>> daemon_pids);
+  std::string asok_request(AdminSocketClient &asok, std::string command, std::string daemon_name);
+};
+
+class Metric {
+private:
+  struct metric_entry {
+    labels_t labels;
+    std::string value;
+  };
+  std::string name;
+  std::string mtype;
+  std::string description;
+  std::vector<metric_entry> entries;
+
+public:
+  Metric(std::string name, std::string mtype, std::string description)
+      : name(name), mtype(mtype), description(description) {}
+  Metric(const Metric &) = default;
+  Metric() = default;
+  void add(labels_t labels, std::string value);
+  std::string dump();
+};
+
+class MetricsBuilder {
+public:
+  virtual ~MetricsBuilder() = default;
+  virtual std::string dump() = 0;
+  virtual void add(std::string value, std::string name, std::string description,
+                   std::string mtype, labels_t labels) = 0;
+
+protected:
+  std::string out;
+};
+
+class OrderedMetricsBuilder : public MetricsBuilder {
+private:
+  std::map<std::string, Metric> metrics;
+
+public:
+  std::string dump();
+  void add(std::string value, std::string name, std::string description,
+           std::string mtype, labels_t labels);
+};
+
+class UnorderedMetricsBuilder : public MetricsBuilder {
+public:
+  std::string dump();
+  void add(std::string value, std::string name, std::string description,
+           std::string mtype, labels_t labels);
+};
+
+DaemonMetricCollector &collector_instance();
diff --git a/src/exporter/ceph_exporter.cc b/src/exporter/ceph_exporter.cc
new file mode 100644
index 00000000000..70650ff87c6
--- /dev/null
+++ b/src/exporter/ceph_exporter.cc
@@ -0,0 +1,65 @@
+#include "common/ceph_argparse.h"
+#include "common/config.h"
+#include "exporter/DaemonMetricCollector.h"
+#include "exporter/http_server.h"
+#include "global/global_init.h"
+#include "global/global_context.h"
+
+#include <boost/thread/thread.hpp>
+#include <iostream>
+#include <map>
+#include <string>
+
+#define dout_context g_ceph_context
+
+static void usage() {
+  std::cout << "usage: ceph-exporter [options]\n"
+            << "options:\n"
+               "  --sock-dir:     The path to ceph daemons socket files dir\n"
+               "  --addrs:        Host ip address where exporter is deployed\n"
+               "  --port:         Port to deploy exporter on. Default is 9926\n"
+               "  --prio-limit:   Only perf counters greater than or equal to prio-limit are fetched. Default: 5\n"
+               "  --stats-period: Time to wait before sending requests again to exporter server (seconds). Default: 5s"
+            << std::endl;
+  generic_server_usage();
+}
+
+int main(int argc, char **argv) {
+
+  auto args = argv_to_vec(argc, argv);
+  if (args.empty()) {
+    std::cerr << argv[0] << ": -h or --help for usage" << std::endl;
+    exit(1);
+  }
+  if (ceph_argparse_need_usage(args)) {
+    usage();
+    exit(0);
+  }
+
+  auto cct = global_init(NULL, args, CEPH_ENTITY_TYPE_CLIENT,
+                         CODE_ENVIRONMENT_DAEMON, 0);
+  std::string val;
+  for (auto i = args.begin(); i != args.end();) {
+    if (ceph_argparse_double_dash(args, i)) {
+      break;
+    } else if (ceph_argparse_witharg(args, i, &val, "--sock-dir", (char *)NULL)) {
+      cct->_conf.set_val("exporter_sock_dir", val);
+    } else if (ceph_argparse_witharg(args, i, &val, "--addrs", (char *)NULL)) {
+      cct->_conf.set_val("exporter_addr", val);
+    } else if (ceph_argparse_witharg(args, i, &val, "--port", (char *)NULL)) {
+      cct->_conf.set_val("exporter_http_port", val);
+    } else if (ceph_argparse_witharg(args, i, &val, "--prio-limit", (char *)NULL)) {
+      cct->_conf.set_val("exporter_prio_limit", val);
+    } else if (ceph_argparse_witharg(args, i, &val, "--stats-period", (char *)NULL)) {
+      cct->_conf.set_val("exporter_stats_period", val);
+    } else {
+      ++i;
+    }
+  }
+  common_init_finish(g_ceph_context);
+
+  boost::thread server_thread(http_server_thread_entrypoint);
+  DaemonMetricCollector &collector = collector_instance();
+  collector.main();
+  server_thread.join();
+}
diff --git a/src/exporter/http_server.cc b/src/exporter/http_server.cc
new file mode 100644
index 00000000000..317d877e88c
--- /dev/null
+++ b/src/exporter/http_server.cc
@@ -0,0 +1,169 @@
+#include "http_server.h"
+#include "common/debug.h"
+#include "common/hostname.h"
+#include "global/global_init.h"
+#include "global/global_context.h"
+#include "exporter/DaemonMetricCollector.h"
+
+#include <boost/asio.hpp>
+#include <boost/beast/core.hpp>
+#include <boost/beast/http.hpp>
+#include <boost/beast/version.hpp>
+#include <boost/thread/thread.hpp>
+#include <chrono>
+#include <cstdlib>
+#include <ctime>
+#include <iostream>
+#include <map>
+#include <memory>
+#include <string>
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_ceph_exporter
+
+namespace beast = boost::beast;   // from <boost/beast.hpp>
+namespace http = beast::http;     // from <boost/beast/http.hpp>
+namespace net = boost::asio;      // from <boost/asio.hpp>
+using tcp = boost::asio::ip::tcp; // from <boost/asio/ip/tcp.hpp>
+
+class http_connection : public std::enable_shared_from_this<http_connection> {
+public:
+  http_connection(tcp::socket socket) : socket_(std::move(socket)) {}
+
+  // Initiate the asynchronous operations associated with the connection.
+  void start() {
+    read_request();
+    check_deadline();
+  }
+
+private:
+  tcp::socket socket_;
+  beast::flat_buffer buffer_{8192};
+  http::request<http::dynamic_body> request_;
+  http::response<http::string_body> response_;
+
+  net::steady_timer deadline_{socket_.get_executor(), std::chrono::seconds(60)};
+
+  // Asynchronously receive a complete request message.
+  void read_request() {
+    auto self = shared_from_this();
+
+    http::async_read(socket_, buffer_, request_,
+                     [self](beast::error_code ec, std::size_t bytes_transferred) {
+                       boost::ignore_unused(bytes_transferred);
+                       if (ec) {
+                         dout(1) << "ERROR: " << ec.message() << dendl;
+                         return;
+                       }
+                       else {
+                         self->process_request();
+                       }
+                     });
+  }
+
+  // Determine what needs to be done with the request message.
+  void process_request() {
+    response_.version(request_.version());
+    response_.keep_alive(request_.keep_alive());
+
+    switch (request_.method()) {
+    case http::verb::get:
+      response_.result(http::status::ok);
+      create_response();
+      break;
+
+    default:
+      // We return responses indicating an error if
+      // we do not recognize the request method.
+      response_.result(http::status::method_not_allowed);
+      response_.set(http::field::content_type, "text/plain");
+      std::string body("Invalid request-method '" +
+                       std::string(request_.method_string()) + "'");
+      response_.body() = body;
+      break;
+    }
+
+    write_response();
+  }
+
+  // Construct a response message based on the program state.
+  void create_response() {
+    if (request_.target() == "/") {
+      response_.set(http::field::content_type, "text/html; charset=utf-8");
+      std::string body("<html>\n"
+                       "<head><title>Ceph Exporter</title></head>\n"
+                       "<body>\n"
+                       "<h1>Ceph Exporter</h1>\n"
+                       "<p><a href='/metrics'>Metrics</a></p>"
+                       "</body>\n"
+                       "</html>\n");
+      response_.body() = body;
+    } else if (request_.target() == "/metrics") {
+      response_.set(http::field::content_type, "text/plain; charset=utf-8");
+      DaemonMetricCollector &collector = collector_instance();
+      std::string metrics = collector.get_metrics();
+      response_.body() = metrics;
+    } else {
+      response_.result(http::status::method_not_allowed);
+      response_.set(http::field::content_type, "text/plain");
+      response_.body() = "File not found \n";
+    }
+  }
+
+  // Asynchronously transmit the response message.
+  void write_response() {
+    auto self = shared_from_this();
+
+    response_.prepare_payload();
+
+    http::async_write(socket_, response_,
+                      [self](beast::error_code ec, std::size_t) {
+                        self->socket_.shutdown(tcp::socket::shutdown_send, ec);
+                        self->deadline_.cancel();
+                        if (ec) {
+                          dout(1) << "ERROR: " << ec.message() << dendl;
+                          return;
+                        }
+                      });
+  }
+
+  // Check whether we have spent enough time on this connection.
+  void check_deadline() {
+    auto self = shared_from_this();
+
+    deadline_.async_wait([self](beast::error_code ec) {
+      if (!ec) {
+        // Close socket to cancel any outstanding operation.
+        self->socket_.close(ec);
+      }
+    });
+  }
+};
+
+// "Loop" forever accepting new connections.
+void http_server(tcp::acceptor &acceptor, tcp::socket &socket) {
+  acceptor.async_accept(socket, [&](beast::error_code ec) {
+    if (!ec)
+      std::make_shared<http_connection>(std::move(socket))->start();
+    http_server(acceptor, socket);
+  });
+}
+
+void http_server_thread_entrypoint() {
+  try {
+    std::string exporter_addr = g_conf().get_val<std::string>("exporter_addr");
+    auto const address = net::ip::make_address(exporter_addr);
+    unsigned short port = g_conf().get_val<int64_t>("exporter_http_port");
+
+    net::io_context ioc{1};
+
+    tcp::acceptor acceptor{ioc, {address, port}};
+    tcp::socket socket{ioc};
+    http_server(acceptor, socket);
+    dout(1) << "Http server running on " << exporter_addr << ":" << port << dendl;
+    ioc.run();
+  } catch (std::exception const &e) {
+    dout(1) << "Error: " << e.what() << dendl;
+    exit(EXIT_FAILURE);
+  }
+}
diff --git a/src/exporter/http_server.h b/src/exporter/http_server.h
new file mode 100644
index 00000000000..0d0502f57c8
--- /dev/null
+++ b/src/exporter/http_server.h
@@ -0,0 +1,5 @@
+#pragma once
+
+#include <string>
+
+void http_server_thread_entrypoint();
diff --git a/src/exporter/util.cc b/src/exporter/util.cc
new file mode 100644
index 00000000000..0ae190cc642
--- /dev/null
+++ b/src/exporter/util.cc
@@ -0,0 +1,48 @@
+#include "util.h"
+#include "common/debug.h"
+#include <boost/algorithm/string/classification.hpp>
+#include <cctype>
+#include <chrono>
+#include <fstream>
+#include <iostream>
+#include <sstream>
+
+#define dout_context g_ceph_context
+#define dout_subsys ceph_subsys_ceph_exporter
+
+BlockTimer::BlockTimer(std::string file, std::string function)
+	: file(file), function(function), stopped(false) {
+	t1 = std::chrono::high_resolution_clock::now();
+}
+BlockTimer::~BlockTimer() {
+  dout(20) << file << ":" << function << ": " << ms.count() << "ms" << dendl;
+}
+
+// useful with stop
+double BlockTimer::get_ms() {
+	return ms.count();
+}
+
+// Manually stop the timer as you might want to get the time
+void BlockTimer::stop() {
+	if (!stopped) {
+		stopped = true;
+		t2 = std::chrono::high_resolution_clock::now();
+		ms = t2 - t1;
+	}
+}
+
+bool string_is_digit(std::string s) {
+	size_t i = 0;
+	while (std::isdigit(s[i]) && i < s.size()) {
+		i++;
+	}
+	return i >= s.size();
+}
+
+std::string read_file_to_string(std::string path) {
+	std::ifstream is(path);
+	std::stringstream buffer;
+	buffer << is.rdbuf();
+	return buffer.str();
+}
diff --git a/src/exporter/util.h b/src/exporter/util.h
new file mode 100644
index 00000000000..b1fb83ad813
--- /dev/null
+++ b/src/exporter/util.h
@@ -0,0 +1,22 @@
+#include "common/hostname.h"
+#include <chrono>
+#include <string>
+
+#define TIMED_FUNCTION() BlockTimer timer(__FILE__, __FUNCTION__) 
+
+class BlockTimer {
+ public:
+	BlockTimer(std::string file, std::string function);
+	~BlockTimer();
+	void stop();
+	double get_ms();
+ private:
+	std::chrono::duration<double, std::milli> ms;
+	std::string file, function;
+	bool stopped;
+	std::chrono::time_point<std::chrono::high_resolution_clock> t1, t2;
+};
+
+bool string_is_digit(std::string s);
+std::string read_file_to_string(std::string path);
+std::string get_hostname(std::string path);
-- 
2.39.5