Add Telemetry metrics framework

Signed-off-by: Gagan Juneja <[email protected]>

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/Counter.java

@@ -0,0 +1,31 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.metrics;
+
+import org.opensearch.telemetry.tracing.attributes.Attributes;
+
+/**
+ * Counter adds the value to the existing metric.
+ */
+public interface Counter {
+
+    /**
+     * add value.
+     * @param value value to be added.
+     */
+    void add(double value);
+
+    /**
+     * add value along with the attributes.
+     * @param value value to be added.
+     * @param attributes attributes/dimensions of the metric.
+     */
+    void add(double value, Attributes attributes);
+
+}

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/DefaultMetricsRegistry.java

@@ -0,0 +1,42 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.metrics;
+
+import java.io.Closeable;
+import java.io.IOException;
+
+/**
+ * Default implementation for {@link MetricsRegistry}
+ */
+public class DefaultMetricsRegistry implements MetricsRegistry {
+    private final MetricsTelemetry metricsTelemetry;
+
+    /**
+     * Constructor
+     * @param metricsTelemetry metrics telemetry.
+     */
+    public DefaultMetricsRegistry(MetricsTelemetry metricsTelemetry) {
+        this.metricsTelemetry = metricsTelemetry;
+    }
+
+    @Override
+    public Counter createCounter(String name, String description, String unit) {
+        return metricsTelemetry.createCounter(name, description, unit);
+    }
+
+    @Override
+    public Counter createUpDownCounter(String name, String description, String unit) {
+        return metricsTelemetry.createUpDownCounter(name, description, unit);
+    }
+
+    @Override
+    public void close() throws IOException {
+        ((Closeable) metricsTelemetry).close();
+    }
+}

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/MetricsRegistry.java

@@ -0,0 +1,35 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.metrics;
+
+import java.io.Closeable;
+
+/**
+ * MetricsRegistry helps in creating the metric instruments.
+ */
+public interface MetricsRegistry extends Closeable {
+
+    /**
+     * Creates the counter.
+     * @param name name of the counter.
+     * @param description any description about the metric.
+     * @param unit unit of the metric.
+     * @return counter.
+     */
+    Counter createCounter(String name, String description, String unit);
+
+    /**
+     * Creates the upDown counter.
+     * @param name name of the upDown counter.
+     * @param description any description about the metric.
+     * @param unit unit of the metric.
+     * @return counter.
+     */
+    Counter createUpDownCounter(String name, String description, String unit);
+}

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/MetricsTelemetry.java

@@ -10,12 +10,31 @@
 
 import org.opensearch.common.annotation.ExperimentalApi;
 
+import java.io.Closeable;
+
 /**
  * Interface for metrics telemetry providers
   *
  * @opensearch.experimental
  */
 @ExperimentalApi
-public interface MetricsTelemetry {
+public interface MetricsTelemetry extends Closeable {
+
+    /**
+     * Creates the counter.
+     * @param name name of the counter.
+     * @param description any description about the metric.
+     * @param unit unit of the metric.
+     * @return counter
+     */
+    Counter createCounter(String name, String description, String unit);
 
+    /**
+     * Creates the upDown counter.
+     * @param name name of the upDown counter.
+     * @param description any description about the metric.
+     * @param unit unit of the metric.
+     * @return upDownCounter.
+     */
+    Counter createUpDownCounter(String name, String description, String unit);
 }

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/noop/NoopCounter.java

@@ -0,0 +1,35 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.metrics.noop;
+
+import org.opensearch.telemetry.metrics.Counter;
+import org.opensearch.telemetry.tracing.attributes.Attributes;
+
+/**
+ * No-op {@link Counter}
+ */
+public class NoopCounter implements Counter {
+
+    /**
+     * No-op Counter instance
+     */
+    public final static NoopCounter INSTANCE = new NoopCounter();
+
+    private NoopCounter() {}
+
+    @Override
+    public void add(double value) {
+
+    }
+
+    @Override
+    public void add(double value, Attributes attributes) {
+
+    }
+}

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/noop/NoopMetricsRegistry.java

@@ -0,0 +1,42 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.metrics.noop;
+
+import org.opensearch.telemetry.metrics.Counter;
+import org.opensearch.telemetry.metrics.MetricsRegistry;
+
+import java.io.IOException;
+
+/**
+ *No-op {@link MetricsRegistry}
+ */
+public class NoopMetricsRegistry implements MetricsRegistry {
+
+    /**
+     * No-op Meter instance
+     */
+    public final static NoopMetricsRegistry INSTANCE = new NoopMetricsRegistry();
+
+    private NoopMetricsRegistry() {}
+
+    @Override
+    public Counter createCounter(String name, String description, String unit) {
+        return NoopCounter.INSTANCE;
+    }
+
+    @Override
+    public Counter createUpDownCounter(String name, String description, String unit) {
+        return NoopCounter.INSTANCE;
+    }
+
+    @Override
+    public void close() throws IOException {
+
+    }
+}

libs/telemetry/src/main/java/org/opensearch/telemetry/metrics/noop/package-info.java

@@ -0,0 +1,12 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+/**
+ * Contains metrics related classes
+ */
+package org.opensearch.telemetry.metrics.noop;

libs/telemetry/src/test/java/org/opensearch/telemetry/metrics/DefaultMetricsRegistryTests.java

@@ -0,0 +1,51 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.telemetry.metrics;
+
+import org.opensearch.test.OpenSearchTestCase;
+
+import static org.mockito.ArgumentMatchers.any;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.when;
+
+public class DefaultMetricsRegistryTests extends OpenSearchTestCase {
+
+    private MetricsTelemetry metricsTelemetry;
+    private DefaultMetricsRegistry defaultMeterRegistry;
+
+    @Override
+    public void setUp() throws Exception {
+        super.setUp();
+        metricsTelemetry = mock(MetricsTelemetry.class);
+        defaultMeterRegistry = new DefaultMetricsRegistry(metricsTelemetry);
+    }
+
+    public void testCounter() {
+        Counter mockCounter = mock(Counter.class);
+        when(defaultMeterRegistry.createCounter(any(String.class), any(String.class), any(String.class))).thenReturn(mockCounter);
+        Counter counter = defaultMeterRegistry.createCounter(
+            "org.opensearch.telemetry.metrics.DefaultMeterRegistryTests.testCounter",
+            "test counter",
+            "1"
+        );
+        assertSame(mockCounter, counter);
+    }
+
+    public void testUpDownCounter() {
+        Counter mockCounter = mock(Counter.class);
+        when(defaultMeterRegistry.createUpDownCounter(any(String.class), any(String.class), any(String.class))).thenReturn(mockCounter);
+        Counter counter = defaultMeterRegistry.createUpDownCounter(
+            "org.opensearch.telemetry.metrics.DefaultMeterRegistryTests.testUpDownCounter",
+            "test up-down counter",
+            "1"
+        );
+        assertSame(mockCounter, counter);
+    }
+
+}

plugins/telemetry-otel/build.gradle

@@ -37,6 +37,7 @@ dependencies {
   runtimeOnly "com.squareup.okhttp3:okhttp:4.11.0"
   runtimeOnly "com.squareup.okio:okio-jvm:3.5.0"
   runtimeOnly "io.opentelemetry:opentelemetry-exporter-sender-okhttp:${versions.opentelemetry}"
+  api "io.opentelemetry:opentelemetry-extension-incubator:${versions.opentelemetry}-alpha"
   testImplementation "io.opentelemetry:opentelemetry-sdk-testing:${versions.opentelemetry}"
 }
 
@@ -80,29 +81,12 @@ thirdPartyAudit {
     'io.opentelemetry.api.events.EventEmitter',
     'io.opentelemetry.api.events.EventEmitterBuilder',
     'io.opentelemetry.api.events.EventEmitterProvider',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedDoubleHistogramBuilder',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedLongHistogramBuilder',
     'io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties',
     'io.opentelemetry.sdk.autoconfigure.spi.logs.ConfigurableLogRecordExporterProvider',
     'io.opentelemetry.sdk.autoconfigure.spi.metrics.ConfigurableMetricExporterProvider',
     'io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider',
-    'io.opentelemetry.extension.incubator.metrics.DoubleCounterAdviceConfigurer',
-    'io.opentelemetry.extension.incubator.metrics.DoubleGauge',
-    'io.opentelemetry.extension.incubator.metrics.DoubleGaugeAdviceConfigurer',
-    'io.opentelemetry.extension.incubator.metrics.DoubleHistogramAdviceConfigurer',
-    'io.opentelemetry.extension.incubator.metrics.DoubleUpDownCounterAdviceConfigurer',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedDoubleCounterBuilder',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedDoubleGaugeBuilder',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedDoubleUpDownCounterBuilder',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedLongCounterBuilder',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedLongGaugeBuilder',
-    'io.opentelemetry.extension.incubator.metrics.ExtendedLongUpDownCounterBuilder',
-    'io.opentelemetry.extension.incubator.metrics.LongCounterAdviceConfigurer',
-    'io.opentelemetry.extension.incubator.metrics.LongGauge',
-    'io.opentelemetry.extension.incubator.metrics.LongGaugeAdviceConfigurer',
-    'io.opentelemetry.extension.incubator.metrics.LongHistogramAdviceConfigurer',
-    'io.opentelemetry.extension.incubator.metrics.LongUpDownCounterAdviceConfigurer',
-    'kotlin.io.path.PathsKt'
+    'kotlin.io.path.PathsKt',
+    'io.opentelemetry.sdk.autoconfigure.spi.traces.ConfigurableSpanExporterProvider'
   )
 }
 

plugins/telemetry-otel/licenses/opentelemetry-extension-incubator-1.30.1-alpha.jar.sha1

@@ -0,0 +1 @@
+bfcea9bd71f97dd4e8a4f92c15ba5659fb07ff05