Add tracing support to send information to the WebJobs extension

[bachuv]

Issue describing the changes in this PR

This PR adds distributed tracing support to send traceparent and tracestate information to the WebJobs extension.Customers can create a new span in their client function and set that as the current span. In scheduleNewOrchestrationInstance() we read the current span and add the traceparent and tracestate to the CreateInstanceRequest protobuf property.

I followed the instructions at https://learn.microsoft.com/en-us/azure/azure-functions/opentelemetry-howto?tabs=app-insights&pivots=programming-language-java to test.

Sample Durable Functions code:

package com.function;

import java.util.Optional;
import java.util.logging.Level;

import com.azure.monitor.opentelemetry.exporter.AzureMonitorExporterBuilder;
import com.microsoft.azure.functions.ExecutionContext;
import com.microsoft.azure.functions.HttpMethod;
import com.microsoft.azure.functions.HttpRequestMessage;
import com.microsoft.azure.functions.HttpResponseMessage;
import com.microsoft.azure.functions.annotation.AuthorizationLevel;
import com.microsoft.azure.functions.annotation.FunctionName;
import com.microsoft.azure.functions.annotation.HttpTrigger;
import com.microsoft.durabletask.DurableTaskClient;
import com.microsoft.durabletask.NewOrchestrationInstanceOptions;
import com.microsoft.durabletask.TaskOrchestrationContext;
import com.microsoft.durabletask.azurefunctions.DurableActivityTrigger;
import com.microsoft.durabletask.azurefunctions.DurableClientContext;
import com.microsoft.durabletask.azurefunctions.DurableClientInput;
import com.microsoft.durabletask.azurefunctions.DurableOrchestrationTrigger;

import io.opentelemetry.api.common.AttributeKey;
import io.opentelemetry.api.common.Attributes;
import io.opentelemetry.api.trace.Span;
import io.opentelemetry.api.trace.SpanKind;
import io.opentelemetry.api.trace.Tracer;
import io.opentelemetry.context.Scope;
import io.opentelemetry.sdk.OpenTelemetrySdk;
import io.opentelemetry.sdk.resources.Resource;
import io.opentelemetry.sdk.trace.SdkTracerProvider;
import io.opentelemetry.sdk.trace.export.BatchSpanProcessor;
import io.opentelemetry.sdk.trace.export.SpanExporter;

@FunctionName("StartOrchestration")
    public HttpResponseMessage startOrchestration(
            @HttpTrigger(name = "req", methods = {HttpMethod.GET, HttpMethod.POST}, authLevel = AuthorizationLevel.ANONYMOUS) HttpRequestMessage<Optional<String>> request,
            @DurableClientInput(name = "durableContext") DurableClientContext durableContext,
            final ExecutionContext context) {
        context.getLogger().info("Java HTTP trigger processed a request.");

        Tracer tracer = initTracer();
        Span span = tracer.spanBuilder("StartOrchestration").setSpanKind(SpanKind.CLIENT).startSpan();
    
        try (Scope scope = span.makeCurrent()) {
            context.getLogger().info("Java HTTP trigger processed a request.");
           
            DurableTaskClient client = durableContext.getClient();
            String instanceId = client.scheduleNewOrchestrationInstance("Cities", options);
            context.getLogger().log(Level.INFO, "Created new Java orchestration with instance ID = {0}", instanceId);
            return durableContext.createCheckStatusResponse(request, instanceId);
        } finally {
            span.end();
        }
    }

  /**
     * This is the orchestrator function, which can schedule activity functions, create durable timers,
     * or wait for external events in a way that's completely fault-tolerant.
     */
    @FunctionName("Cities")
    public String citiesOrchestrator(
            @DurableOrchestrationTrigger(name = "ctx") TaskOrchestrationContext ctx) {
        String result = "";
        result += ctx.callActivity("Capitalize", "Tokyo", String.class).await() + ", ";
        result += ctx.callActivity("Capitalize", "London", String.class).await() + ", ";
        result += ctx.callActivity("Capitalize", "Seattle", String.class).await() + ", ";
        result += ctx.callActivity("Capitalize", "Austin", String.class).await();
        return result;
    }

    /**
     * This is the activity function that gets invoked by the orchestration.
     */
    @FunctionName("Capitalize")
    public String capitalize(
            @DurableActivityTrigger(name = "name") String name,
            final ExecutionContext context) {
        context.getLogger().info("Capitalizing: " + name);
        return name.toUpperCase();
    }

   private static Tracer initTracer() {
        String connectionString = System.getenv("APPLICATIONINSIGHTS_CONNECTION_STRING");
    
        SpanExporter exporter = new AzureMonitorExporterBuilder()
            .connectionString(connectionString)
            .buildTraceExporter();
    
        SdkTracerProvider tracerProvider = SdkTracerProvider.builder()
        .addSpanProcessor(BatchSpanProcessor.builder(exporter).build())
        .setResource(Resource.create(
            Attributes.of(AttributeKey.stringKey("service.name"), "java-functions")
        ))
        .build();
    
        return OpenTelemetrySdk.builder()
            .setTracerProvider(tracerProvider)
            .build()
            .getTracer("java-functions");
    }

pom.xml dependencies

<dependencies>
        <dependency>
            <groupId>com.microsoft.azure.functions</groupId>
            <artifactId>azure-functions-java-library</artifactId>
            <version>${azure.functions.java.library.version}</version>
        </dependency>
        <!-- Test -->
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter</artifactId>
            <version>5.4.2</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-core</artifactId>
            <version>2.23.4</version>
            <scope>test</scope>
        </dependency>

        <!-- Durable -->
        <dependency>
            <groupId>com.microsoft</groupId>
            <artifactId>durabletask-azure-functions</artifactId>
            <version>1.5.0</version>
        </dependency>

        <dependency>
            <groupId>com.microsoft</groupId>
            <artifactId>durabletask-client</artifactId>
            <version>1.5.0</version>
        </dependency>

        <!-- Jackson Core -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.15.3</version>
        </dependency>

        <!-- Jackson Databind -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>2.15.3</version>
        </dependency>

        <!-- Jackson Annotations -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>2.15.3</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-netty-shaded</artifactId>
            <version>1.59.0</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-protobuf</artifactId>
            <version>1.59.0</version>
        </dependency>

        <dependency>
            <groupId>io.grpc</groupId>
            <artifactId>grpc-stub</artifactId>
            <version>1.59.0</version>
        </dependency>

        <!-- Tracing -->

        <!-- OpenTelemetry API (core tracing API) -->
        <dependency>
            <groupId>io.opentelemetry</groupId>
            <artifactId>opentelemetry-api</artifactId>
            <version>1.34.0</version>
        </dependency>

        <!-- OpenTelemetry SDK (required for manual span creation and exporting) -->
        <dependency>
            <groupId>io.opentelemetry</groupId>
            <artifactId>opentelemetry-sdk</artifactId>
            <version>1.34.0</version>
        </dependency>

        <!-- OpenTelemetry Context Propagation -->
        <dependency>
            <groupId>io.opentelemetry</groupId>
            <artifactId>opentelemetry-context</artifactId>
            <version>1.34.0</version>
        </dependency>

        <!-- Azure Monitor Exporter for OpenTelemetry -->
        <dependency>
            <groupId>com.azure</groupId>
            <artifactId>azure-monitor-opentelemetry-exporter</artifactId>
            <version>1.0.0-beta.16</version>
        </dependency>

    </dependencies>

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes are added to the CHANGELOG.md
• I have added all required tests (Unit tests, E2E tests)

[cgillum]

Looks good except for the handling of trace state, which I had some questions on above.

[cgillum]