[metric][feat]improve metrics (#692)

include/ylt/metric.hpp

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2024, Alibaba Group Holding Limited;
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#pragma once
+#define CINATRA_ENABLE_METRIC_JSON
+#include "metric/gauge.hpp"
+#include "metric/histogram.hpp"
+#include "metric/metric.hpp"
+#include "metric/summary.hpp"
+#include "ylt/struct_json/json_writer.h"

include/ylt/metric/counter.hpp

@@ -4,13 +4,23 @@
 
 #include "metric.hpp"
 
-namespace ylt {
+namespace ylt::metric {
 enum class op_type_t { INC, DEC, SET };
-struct counter_sample {
-  op_type_t op_type;
-  std::vector<std::string> labels_value;
-  double value;
+
+#ifdef CINATRA_ENABLE_METRIC_JSON
+struct json_counter_metric_t {
+  std::unordered_multimap<std::string, std::string> labels;
+  int64_t value;
+};
+REFLECTION(json_counter_metric_t, labels, value);
+struct json_counter_t {
+  std::string name;
+  std::string help;
+  std::string type;
+  std::vector<json_counter_metric_t> metrics;
 };
+REFLECTION(json_counter_t, name, help, type, metrics);
+#endif
 
 class counter_t : public metric_t {
  public:
@@ -23,12 +33,8 @@ class counter_t : public metric_t {
   // static labels value, contains a map with atomic value.
   counter_t(std::string name, std::string help,
             std::map<std::string, std::string> labels)
-      : metric_t(MetricType::Counter, std::move(name), std::move(help)) {
-    for (auto &[k, v] : labels) {
-      labels_name_.push_back(k);
-      labels_value_.push_back(v);
-    }
-
+      : metric_t(MetricType::Counter, std::move(name), std::move(help),
+                 std::move(labels)) {
     atomic_value_map_.emplace(labels_value_, 0);
     use_atomic_ = true;
   }
@@ -56,7 +62,7 @@ class counter_t : public metric_t {
 
   std::map<std::vector<std::string>, double,
            std::less<std::vector<std::string>>>
-  value_map() {
+  value_map() override {
     std::map<std::vector<std::string>, double,
              std::less<std::vector<std::string>>>
         map;
@@ -97,6 +103,44 @@ class counter_t : public metric_t {
     }
   }
 
+#ifdef CINATRA_ENABLE_METRIC_JSON
+  void serialize_to_json(std::string &str) override {
+    std::string s;
+    if (labels_name_.empty()) {
+      if (default_lable_value_ == 0) {
+        return;
+      }
+      json_counter_t counter{name_, help_, std::string(metric_name())};
+      int64_t value = default_lable_value_;
+      counter.metrics.push_back({{}, value});
+      iguana::to_json(counter, str);
+      return;
+    }
+
+    json_counter_t counter{name_, help_, std::string(metric_name())};
+    if (use_atomic_) {
+      to_json(counter, atomic_value_map_, str);
+    }
+    else {
+      to_json(counter, value_map_, str);
+    }
+  }
+
+  template <typename T>
+  void to_json(json_counter_t &counter, T &map, std::string &str) {
+    for (auto &[k, v] : map) {
+      json_counter_metric_t metric;
+      size_t index = 0;
+      for (auto &label_value : k) {
+        metric.labels.emplace(labels_name_[index++], label_value);
+      }
+      metric.value = (int64_t)v;
+      counter.metrics.push_back(std::move(metric));
+    }
+    iguana::to_json(counter, str);
+  }
+#endif
+
   void inc(double val = 1) {
     if (val < 0) {
       throw std::invalid_argument("the value is less than zero");
@@ -255,4 +299,4 @@ class counter_t : public metric_t {
            std::less<std::vector<std::string>>>
       value_map_;
 };
-}  // namespace ylt
+}  // namespace ylt::metric

include/ylt/metric/detail/ckms_quantiles.hpp

@@ -5,7 +5,7 @@
 
 // https://github.com/jupp0r/prometheus-cpp/blob/master/core/include/prometheus/detail/ckms_quantiles.h
 
-namespace ylt {
+namespace ylt::metric {
 class CKMSQuantiles {
  public:
   struct Quantile {
@@ -172,4 +172,4 @@ class CKMSQuantiles {
   std::array<double, 500> buffer_;
   std::size_t buffer_count_;
 };
-}  // namespace ylt
+}  // namespace ylt::metric

include/ylt/metric/detail/time_window_quantiles.hpp

@@ -2,7 +2,7 @@
 #include "ckms_quantiles.hpp"
 // https://github.com/jupp0r/prometheus-cpp/blob/master/core/include/prometheus/detail/time_window_quantiles.h
 
-namespace ylt {
+namespace ylt::metric {
 class TimeWindowQuantiles {
   using Clock = std::chrono::steady_clock;
 
@@ -49,4 +49,4 @@ class TimeWindowQuantiles {
   mutable Clock::time_point last_rotation_;
   const Clock::duration rotation_interval_;
 };
-}  // namespace ylt
+}  // namespace ylt::metric

include/ylt/metric/gauge.hpp

@@ -3,7 +3,7 @@
 
 #include "counter.hpp"
 
-namespace ylt {
+namespace ylt::metric {
 class gauge_t : public counter_t {
  public:
   gauge_t(std::string name, std::string help)
@@ -49,4 +49,4 @@ class gauge_t : public counter_t {
     }
   }
 };
-}  // namespace ylt
+}  // namespace ylt::metric