[exporters/prometheus] More namespace cleanup

exporters/prometheus/include/opentelemetry/exporters/prometheus/collector.h

@@ -12,8 +12,6 @@
 #include "opentelemetry/exporters/prometheus/exporter_utils.h"
 #include "opentelemetry/sdk/metrics/metric_reader.h"
 
-namespace prometheus_client = ::prometheus;
-
 OPENTELEMETRY_BEGIN_NAMESPACE
 namespace exporter
 {
@@ -22,7 +20,7 @@ namespace metrics
 /**
  * The Prometheus Collector maintains the intermediate collection in Prometheus Exporter
  */
-class PrometheusCollector : public prometheus_client::Collectable
+class PrometheusCollector : public ::prometheus::Collectable
 {
 public:
   /**
@@ -38,7 +36,7 @@ class PrometheusCollector : public prometheus_client::Collectable
    *
    * @return all metrics in the metricsToCollect snapshot
    */
-  std::vector<prometheus_client::MetricFamily> Collect() const override;
+  std::vector<::prometheus::MetricFamily> Collect() const override;
 
 private:
   sdk::metrics::MetricReader *reader_;

exporters/prometheus/src/collector.cc

@@ -4,9 +4,11 @@
 #include "opentelemetry/exporters/prometheus/collector.h"
 #include "opentelemetry/sdk/common/global_log_handler.h"
 
-namespace metric_sdk = opentelemetry::sdk::metrics;
 
 OPENTELEMETRY_BEGIN_NAMESPACE
+
+namespace metric_sdk = sdk::metrics;
+
 namespace exporter
 {
 namespace metrics
@@ -24,7 +26,7 @@ PrometheusCollector::PrometheusCollector(sdk::metrics::MetricReader *reader) : r
  *
  * @return all metrics in the metricsToCollect snapshot
  */
-std::vector<prometheus_client::MetricFamily> PrometheusCollector::Collect() const
+std::vector<::prometheus::MetricFamily> PrometheusCollector::Collect() const
 {
   if (reader_->IsShutdown())
   {
@@ -35,7 +37,7 @@ std::vector<prometheus_client::MetricFamily> PrometheusCollector::Collect() cons
   }
   collection_lock_.lock();
 
-  std::vector<prometheus_client::MetricFamily> result;
+  std::vector<::prometheus::MetricFamily> result;
   reader_->Collect([&result](sdk::metrics::ResourceMetrics &metric_data) {
     auto prometheus_metric_data = TranslateToPrometheus(metric_data);
     for (auto &data : prometheus_metric_data)

exporters/prometheus/src/exporter_utils.cc

@@ -12,10 +12,10 @@
 
 #include "opentelemetry/sdk/common/global_log_handler.h"
 
-namespace prometheus_client = ::prometheus;
-namespace metric_sdk        = opentelemetry::sdk::metrics;
-
 OPENTELEMETRY_BEGIN_NAMESPACE
+
+namespace metric_sdk = sdk::metrics;
+
 namespace exporter
 {
 namespace metrics
@@ -47,28 +47,28 @@ metric_sdk::AggregationType getAggregationType(const metric_sdk::PointType &poin
 /**
  * Translate the OTel metric type to Prometheus metric type
  */
-prometheus_client::MetricType TranslateType(metric_sdk::AggregationType kind, bool is_monotonic)
+::prometheus::MetricType TranslateType(metric_sdk::AggregationType kind, bool is_monotonic)
 {
   switch (kind)
   {
     case metric_sdk::AggregationType::kSum:
       if (!is_monotonic)
       {
-        return prometheus_client::MetricType::Gauge;
+        return ::prometheus::MetricType::Gauge;
       }
       else
       {
-        return prometheus_client::MetricType::Counter;
+        return ::prometheus::MetricType::Counter;
       }
       break;
     case metric_sdk::AggregationType::kHistogram:
-      return prometheus_client::MetricType::Histogram;
+      return ::prometheus::MetricType::Histogram;
       break;
     case metric_sdk::AggregationType::kLastValue:
-      return prometheus_client::MetricType::Gauge;
+      return ::prometheus::MetricType::Gauge;
       break;
     default:
-      return prometheus_client::MetricType::Untyped;
+      return ::prometheus::MetricType::Untyped;
   }
 }
 
@@ -184,7 +184,7 @@ struct ClientMetricWrapper
    * Handle Counter.
    */
   template <typename T>
-  void SetValue(const std::vector<T> &values, prometheus_client::MetricType type)
+  void SetValue(const std::vector<T> &values, ::prometheus::MetricType type)
   {
     double value          = 0.0;
     const auto &value_var = values[0];
@@ -199,15 +199,15 @@ struct ClientMetricWrapper
 
     switch (type)
     {
-      case prometheus_client::MetricType::Counter: {
+      case ::prometheus::MetricType::Counter: {
         metric.counter.value = value;
         break;
       }
-      case prometheus_client::MetricType::Gauge: {
+      case ::prometheus::MetricType::Gauge: {
         metric.gauge.value = value;
         break;
       }
-      case prometheus_client::MetricType::Untyped: {
+      case ::prometheus::MetricType::Untyped: {
         metric.untyped.value = value;
         break;
       }
@@ -226,18 +226,18 @@ struct ClientMetricWrapper
     metric.histogram.sample_sum   = values[0];
     metric.histogram.sample_count = values[1];
     int cumulative                = 0;
-    std::vector<prometheus_client::ClientMetric::Bucket> buckets;
+    std::vector<::prometheus::ClientMetric::Bucket> buckets;
     uint32_t idx = 0;
     for (const auto &boundary : boundaries)
     {
-      prometheus_client::ClientMetric::Bucket bucket;
+      ::prometheus::ClientMetric::Bucket bucket;
       cumulative += counts[idx];
       bucket.cumulative_count = cumulative;
       bucket.upper_bound      = boundary;
       buckets.emplace_back(bucket);
       ++idx;
     }
-    prometheus_client::ClientMetric::Bucket bucket;
+    ::prometheus::ClientMetric::Bucket bucket;
     cumulative += counts[idx];
     bucket.cumulative_count = cumulative;
     bucket.upper_bound      = std::numeric_limits<double>::infinity();
@@ -268,12 +268,12 @@ struct MetricFamilyWrapper
  * @param records a collection of metrics in OpenTelemetry
  * @return a collection of translated metrics that is acceptable by Prometheus
  */
-std::vector<prometheus_client::MetricFamily> TranslateToPrometheus(
+std::vector<::prometheus::MetricFamily> TranslateToPrometheus(
     const sdk::metrics::ResourceMetrics &data)
 {
 
   // initialize output vector
-  std::vector<prometheus_client::MetricFamily> output;
+  std::vector<::prometheus::MetricFamily> output;
 
   for (const auto &instrumentation_info : data.scope_metric_data_)
   {
@@ -282,7 +282,7 @@ std::vector<prometheus_client::MetricFamily> TranslateToPrometheus(
       auto origin_name = metric_data.instrument_descriptor.name_;
       auto unit        = metric_data.instrument_descriptor.unit_;
       auto sanitized   = SanitizeNames(origin_name);
-      prometheus_client::MetricFamily metric_family;
+      ::prometheus::MetricFamily metric_family;
       metric_family.name = sanitized + "_" + unit;
       metric_family.help = metric_data.instrument_descriptor.description_;
       for (const auto &point_data_attr : metric_data.point_data_attr_)
@@ -294,10 +294,10 @@ std::vector<prometheus_client::MetricFamily> TranslateToPrometheus(
           is_monotonic =
               nostd::get<sdk::metrics::SumPointData>(point_data_attr.point_data).is_monotonic_;
         }
-        const prometheus_client::MetricType type = TranslateType(kind, is_monotonic);
-        metric_family.type                       = type;
+        const ::prometheus::MetricType type = TranslateType(kind, is_monotonic);
+        metric_family.type                  = type;
         MetricFamilyWrapper wrapper{metric_family};
-        if (type == prometheus_client::MetricType::Histogram)  // Histogram
+        if (type == ::prometheus::MetricType::Histogram)  // Histogram
         {
           auto histogram_point_data =
               nostd::get<sdk::metrics::HistogramPointData>(point_data_attr.point_data);
@@ -316,7 +316,7 @@ std::vector<prometheus_client::MetricFamily> TranslateToPrometheus(
               .SetValue(std::vector<double>{sum, (double)histogram_point_data.count_}, boundaries,
                         counts);
         }
-        else if (type == prometheus_client::MetricType::Gauge)
+        else if (type == ::prometheus::MetricType::Gauge)
         {
           if (nostd::holds_alternative<sdk::metrics::LastValuePointData>(
                   point_data_attr.point_data))

exporters/prometheus/test/collector_test.cc

@@ -11,11 +11,13 @@
 #include <map>
 #include <thread>
 
-using opentelemetry::exporter::metrics::PrometheusCollector;
-using opentelemetry::sdk::metrics::ResourceMetrics;
-namespace metric_api      = opentelemetry::metrics;
-namespace metric_sdk      = opentelemetry::sdk::metrics;
-namespace metric_exporter = opentelemetry::exporter::metrics;
+OPENTELEMETRY_BEGIN_NAMESPACE
+
+using exporter::metrics::PrometheusCollector;
+using sdk::metrics::ResourceMetrics;
+namespace metric_api      = metrics;
+namespace metric_sdk      = sdk::metrics;
+namespace metric_exporter = exporter::metrics;
 
 class MockMetricProducer : public opentelemetry::sdk::metrics::MetricProducer
 {
@@ -82,3 +84,5 @@ TEST(PrometheusCollector, BasicTests)
   delete reader;
   delete producer;
 }
+
+OPENTELEMETRY_END_NAMESPACE

exporters/prometheus/test/exporter_test.cc

@@ -9,18 +9,21 @@
 #include "opentelemetry/version.h"
 #include "prometheus_test_helper.h"
 
+OPENTELEMETRY_BEGIN_NAMESPACE
+
 /**
  * PrometheusExporterTest is a friend class of PrometheusExporter.
  * It has access to a private constructor that does not take in
  * an exposer as an argument, and instead takes no arguments; this
  * private constructor is only to be used here for testing
  */
 
-using opentelemetry::exporter::metrics::PrometheusCollector;
-using opentelemetry::exporter::metrics::PrometheusExporter;
-using opentelemetry::exporter::metrics::PrometheusExporterOptions;
-using opentelemetry::sdk::metrics::AggregationTemporality;
-using opentelemetry::sdk::metrics::InstrumentType;
+using exporter::metrics::PrometheusCollector;
+using exporter::metrics::PrometheusExporter;
+using exporter::metrics::PrometheusExporterOptions;
+using sdk::metrics::AggregationTemporality;
+using sdk::metrics::InstrumentType;
+
 /**
  * When a PrometheusExporter is initialized,
  * isShutdown should be false.
@@ -77,3 +80,5 @@ TEST(PrometheusExporter, CheckAggregationTemporality)
   ASSERT_EQ(exporter.GetAggregationTemporality(InstrumentType::kUpDownCounter),
             AggregationTemporality::kCumulative);
 }
+
+OPENTELEMETRY_END_NAMESPACE

exporters/prometheus/test/exporter_utils_test.cc

@@ -13,13 +13,12 @@ OPENTELEMETRY_BEGIN_NAMESPACE
 using exporter::metrics::TranslateToPrometheus;
 namespace metric_sdk        = sdk::metrics;
 namespace metric_api        = metrics;
-namespace prometheus_client = ::prometheus;
 
 template <typename T>
-void assert_basic(prometheus_client::MetricFamily &metric,
+void assert_basic(::prometheus::MetricFamily &metric,
                   const std::string &sanitized_name,
                   const std::string &description,
-                  prometheus_client::MetricType type,
+                  ::prometheus::MetricType type,
                   int label_num,
                   std::vector<T> vals)
 {
@@ -38,23 +37,23 @@ void assert_basic(prometheus_client::MetricFamily &metric,
 
   switch (type)
   {
-    case prometheus_client::MetricType::Counter: {
+    case ::prometheus::MetricType::Counter: {
       ASSERT_DOUBLE_EQ(metric_data.counter.value, vals[0]);
       break;
     }
-    case prometheus_client::MetricType::Histogram: {
+    case ::prometheus::MetricType::Histogram: {
       ASSERT_DOUBLE_EQ(metric_data.histogram.sample_count, vals[0]);
       ASSERT_DOUBLE_EQ(metric_data.histogram.sample_sum, vals[1]);
       auto buckets = metric_data.histogram.bucket;
       ASSERT_EQ(buckets.size(), vals[2]);
       break;
     }
-    case prometheus_client::MetricType::Gauge: {
+    case ::prometheus::MetricType::Gauge: {
       ASSERT_DOUBLE_EQ(metric_data.gauge.value, vals[0]);
       break;
     }
     break;
-    case prometheus_client::MetricType::Summary:
+    case ::prometheus::MetricType::Summary:
       // Summary and Info type not supported
       ASSERT_TRUE(false);
       break;
@@ -65,7 +64,7 @@ void assert_basic(prometheus_client::MetricFamily &metric,
   }
 }
 
-void assert_histogram(prometheus_client::MetricFamily &metric,
+void assert_histogram(::prometheus::MetricFamily &metric,
                       std::list<double> boundaries,
                       std::vector<int> correct)
 {
@@ -105,7 +104,7 @@ TEST(PrometheusExporterUtils, TranslateToPrometheusIntegerCounter)
 
   auto metric1          = translated[0];
   std::vector<int> vals = {10};
-  assert_basic(metric1, "library_name", "description", prometheus_client::MetricType::Counter, 1,
+  assert_basic(metric1, "library_name", "description", ::prometheus::MetricType::Counter, 1,
                vals);
 }
 
@@ -119,7 +118,7 @@ TEST(PrometheusExporterUtils, TranslateToPrometheusIntegerLastValue)
 
   auto metric1          = translated[0];
   std::vector<int> vals = {10};
-  assert_basic(metric1, "library_name", "description", prometheus_client::MetricType::Gauge, 1,
+  assert_basic(metric1, "library_name", "description", ::prometheus::MetricType::Gauge, 1,
                vals);
 }
 
@@ -133,7 +132,7 @@ TEST(PrometheusExporterUtils, TranslateToPrometheusHistogramNormal)
 
   auto metric              = translated[0];
   std::vector<double> vals = {3, 900.5, 4};
-  assert_basic(metric, "library_name", "description", prometheus_client::MetricType::Histogram, 1,
+  assert_basic(metric, "library_name", "description", ::prometheus::MetricType::Histogram, 1,
                vals);
   assert_histogram(metric, std::list<double>{10.1, 20.2, 30.2}, {200, 300, 400, 500});
 }

exporters/prometheus/test/prometheus_test_helper.h

@@ -5,16 +5,18 @@
 
 #include "opentelemetry/version.h"
 
-namespace metric_sdk      = opentelemetry::sdk::metrics;
-namespace nostd           = opentelemetry::nostd;
-namespace exportermetrics = opentelemetry::exporter::metrics;
+OPENTELEMETRY_BEGIN_NAMESPACE
+
+namespace metric_sdk      = sdk::metrics;
+namespace nostd           = nostd;
+namespace exportermetrics = exporter::metrics;
 
 namespace
 {
 
-using opentelemetry::sdk::instrumentationscope::InstrumentationScope;
-using opentelemetry::sdk::resource::Resource;
-using opentelemetry::sdk::resource::ResourceAttributes;
+using sdk::instrumentationscope::InstrumentationScope;
+using sdk::resource::Resource;
+using sdk::resource::ResourceAttributes;
 
 struct TestDataPoints
 {
@@ -123,7 +125,6 @@ struct TestDataPoints
 };
 }  // namespace
 
-OPENTELEMETRY_BEGIN_NAMESPACE
 namespace sdk
 {
 namespace metrics