[PoC] Implement Metric Producer specification

docs/apidiffs/current_vs_latest/opentelemetry-sdk-metrics.txt

@@ -1,2 +1,21 @@
 Comparing source compatibility of  against 
-No changes.
++++  NEW INTERFACE: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.metrics.data.ScopeMetricData  (not serializable)
+	+++  CLASS FILE FORMAT VERSION: 52.0 <- n.a.
+	+++  NEW SUPERCLASS: java.lang.Object
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.metrics.data.Data<?> getData()
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) java.lang.String getDescription()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.GaugeData<io.opentelemetry.sdk.metrics.data.DoublePointData> getDoubleGaugeData()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.SumData<io.opentelemetry.sdk.metrics.data.DoublePointData> getDoubleSumData()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.ExponentialHistogramData getExponentialHistogramData()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.HistogramData getHistogramData()
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.common.InstrumentationScopeInfo getInstrumentationScopeInfo()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.GaugeData<io.opentelemetry.sdk.metrics.data.LongPointData> getLongGaugeData()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.SumData<io.opentelemetry.sdk.metrics.data.LongPointData> getLongSumData()
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) java.lang.String getName()
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.data.SummaryData getSummaryData()
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) io.opentelemetry.sdk.metrics.data.MetricDataType getType()
+	+++  NEW METHOD: PUBLIC(+) ABSTRACT(+) java.lang.String getUnit()
+	+++  NEW METHOD: PUBLIC(+) boolean isEmpty()
+***  MODIFIED CLASS: PUBLIC FINAL io.opentelemetry.sdk.metrics.export.PeriodicMetricReaderBuilder  (not serializable)
+	===  CLASS FILE FORMAT VERSION: 52.0 <- 52.0
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.metrics.export.PeriodicMetricReaderBuilder addMetricProducer(io.opentelemetry.sdk.metrics.internal.export.MetricProducer)

docs/apidiffs/current_vs_latest/opentelemetry-sdk-testing.txt

@@ -1,2 +1,17 @@
 Comparing source compatibility of  against 
-No changes.
+***  MODIFIED CLASS: PUBLIC FINAL io.opentelemetry.sdk.testing.assertj.OpenTelemetryAssertions  (not serializable)
+	===  CLASS FILE FORMAT VERSION: 52.0 <- 52.0
+	+++  NEW METHOD: PUBLIC(+) STATIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert assertThat(io.opentelemetry.sdk.metrics.data.ScopeMetricData)
++++  NEW CLASS: PUBLIC(+) FINAL(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert  (not serializable)
+	+++  CLASS FILE FORMAT VERSION: 52.0 <- n.a.
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasDescription(java.lang.String)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasDoubleGaugeSatisfying(java.util.function.Consumer<io.opentelemetry.sdk.testing.assertj.DoubleGaugeAssert>)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasDoubleSumSatisfying(java.util.function.Consumer<io.opentelemetry.sdk.testing.assertj.DoubleSumAssert>)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasExponentialHistogramSatisfying(java.util.function.Consumer<io.opentelemetry.sdk.testing.assertj.ExponentialHistogramAssert>)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasHistogramSatisfying(java.util.function.Consumer<io.opentelemetry.sdk.testing.assertj.HistogramAssert>)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasInstrumentationScope(io.opentelemetry.sdk.common.InstrumentationScopeInfo)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasLongGaugeSatisfying(java.util.function.Consumer<io.opentelemetry.sdk.testing.assertj.LongGaugeAssert>)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasLongSumSatisfying(java.util.function.Consumer<io.opentelemetry.sdk.testing.assertj.LongSumAssert>)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasName(java.lang.String)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasSummarySatisfying(java.util.function.Consumer<io.opentelemetry.sdk.testing.assertj.SummaryAssert>)
+	+++  NEW METHOD: PUBLIC(+) io.opentelemetry.sdk.testing.assertj.ScopeMetricAssert hasUnit(java.lang.String)

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServer.java

@@ -22,7 +22,10 @@
 import io.opentelemetry.sdk.metrics.data.MetricData;
 import io.opentelemetry.sdk.metrics.export.CollectionRegistration;
 import io.opentelemetry.sdk.metrics.export.MetricReader;
+import io.opentelemetry.sdk.metrics.internal.data.ImmutableMetricData;
 import io.opentelemetry.sdk.metrics.internal.export.MetricProducer;
+import io.opentelemetry.sdk.metrics.internal.export.SdkMetricProducer;
+import io.opentelemetry.sdk.resources.Resource;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.io.UncheckedIOException;
@@ -42,6 +45,7 @@
 import java.util.function.Supplier;
 import java.util.logging.Level;
 import java.util.logging.Logger;
+import java.util.stream.Collectors;
 import java.util.zip.GZIPOutputStream;
 import javax.annotation.Nullable;
 
@@ -59,7 +63,8 @@ public final class PrometheusHttpServer implements MetricReader {
 
   private final HttpServer server;
   private final ExecutorService executor;
-  private volatile MetricProducer metricProducer = MetricProducer.noop();
+  private volatile SdkMetricProducer sdkMetricProducer = SdkMetricProducer.noop();
+  private final List<MetricProducer> registeredProducers;
 
   /**
    * Returns a new {@link PrometheusHttpServer} which can be registered to an {@link
@@ -75,25 +80,37 @@ public static PrometheusHttpServerBuilder builder() {
     return new PrometheusHttpServerBuilder();
   }
 
-  PrometheusHttpServer(String host, int port, ExecutorService executor) {
+  PrometheusHttpServer(
+      String host, int port, ExecutorService executor, List<MetricProducer> registeredProducers) {
     try {
       server = HttpServer.create(new InetSocketAddress(host, port), 3);
     } catch (IOException e) {
       throw new UncheckedIOException("Could not create Prometheus HTTP server", e);
     }
-    MetricsHandler metricsHandler =
-        new MetricsHandler(() -> getMetricProducer().collectAllMetrics());
+    MetricsHandler metricsHandler = new MetricsHandler(() -> getMetricData());
     server.createContext("/", metricsHandler);
     server.createContext("/metrics", metricsHandler);
     server.createContext("/-/healthy", HealthHandler.INSTANCE);
     this.executor = executor;
     server.setExecutor(executor);
+    this.registeredProducers = registeredProducers;
 
     start();
   }
 
-  private MetricProducer getMetricProducer() {
-    return metricProducer;
+  private Collection<MetricData> getMetricData() {
+    Collection<MetricData> metricData = sdkMetricProducer.collectAllMetrics();
+    Resource resource = sdkMetricProducer.getResource();
+    for (MetricProducer metricProducer : registeredProducers) {
+      metricData.addAll(
+          metricProducer.produce().stream()
+              .map(
+                  scopeMetricData -> {
+                    return ImmutableMetricData.createFromScopeMetricData(resource, scopeMetricData);
+                  })
+              .collect(Collectors.toList()));
+    }
+    return metricData;
   }
 
   private void start() {
@@ -114,7 +131,7 @@ private void start() {
 
   @Override
   public void register(CollectionRegistration registration) {
-    this.metricProducer = MetricProducer.asMetricProducer(registration);
+    this.sdkMetricProducer = SdkMetricProducer.asSdkMetricProducer(registration);
   }
 
   @Override

exporters/prometheus/src/main/java/io/opentelemetry/exporter/prometheus/PrometheusHttpServerBuilder.java

@@ -9,6 +9,10 @@
 import static java.util.Objects.requireNonNull;
 
 import io.opentelemetry.sdk.internal.DaemonThreadFactory;
+import io.opentelemetry.sdk.metrics.internal.export.MetricProducer;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import javax.annotation.Nullable;
@@ -24,6 +28,8 @@ public final class PrometheusHttpServerBuilder {
 
   @Nullable private ExecutorService executor;
 
+  private final List<MetricProducer> registeredProducers = new ArrayList<>();
+
   /** Sets the host to bind to. If unset, defaults to {@value #DEFAULT_HOST}. */
   public PrometheusHttpServerBuilder setHost(String host) {
     requireNonNull(host, "host");
@@ -46,6 +52,13 @@ public PrometheusHttpServerBuilder setExecutor(ExecutorService executor) {
     return this;
   }
 
+  /** Adds a {@link MetricProducer} to schedule reads on. */
+  public PrometheusHttpServerBuilder addMetricProducer(MetricProducer producer) {
+    Objects.requireNonNull(producer, "producer");
+    this.registeredProducers.add(producer);
+    return this;
+  }
+
   /**
    * Returns a new {@link PrometheusHttpServer} with the configuration of this builder which can be
    * registered with a {@link io.opentelemetry.sdk.metrics.SdkMeterProvider}.
@@ -55,7 +68,7 @@ public PrometheusHttpServer build() {
     if (executorService == null) {
       executorService = getDefaultExecutor();
     }
-    return new PrometheusHttpServer(host, port, executorService);
+    return new PrometheusHttpServer(host, port, executorService, registeredProducers);
   }
 
   PrometheusHttpServerBuilder() {}