OpenTelemetry support for Google Cloud Trace

Quick start

Cargo.toml:

[dependencies]
opentelemetry-gcloud-trace = "0.19"

Compatibility matrix

Example:

let gcp_trace_exporter = GcpCloudTraceExporterBuilder::for_default_project_id().await?; // or GcpCloudTraceExporterBuilder::new(config_env_var("PROJECT_ID")?)

let tracer_provider = gcp_trace_exporter.create_provider().await?;
let tracer: opentelemetry_sdk::trace::Tracer = gcp_trace_exporter.install(&tracer_provider).await?;

opentelemetry::global::set_tracer_provider(tracer_provider.clone());

tracer.in_span("doing_work_parent", |cx| {
  // ...
});

tracer_provider.shutdown()?;

All examples are available at examples directory.

To run an example use with environment variables:

# PROJECT_ID=<your-google-project-id> cargo run --example enable-exporter

[dependencies]
opentelemetry = { version = "*", features = [] }
opentelemetry_sdk = { version = "*", features = ["rt-tokio"] }
opentelemetry-gcloud-trace = "*"

Configuration

You can specify trace configuration using with_tracer_provider_builder:

   let exporter = GcpCloudTraceExporterBuilder::new(google_project_id);
   let provider = exporter.create_provider_from_builder ( TracerProvider::builder()
         .with_sampler(Sampler::AlwaysOn)
         .with_id_generator(RandomIdGenerator::default())
   ));

Limitations

• This exporter doesn't support any other runtimes except Tokio.

Integration with logs

This crate intentionally doesn't export logs using API to avoid duplicate logs on GKE/GCE environments. You can use this crate in combination with tracing-stackdriver crate to produce JSON formatted logs and logs and traces will be correlated by trace_id and span_id fields automatically.

This is an example of this kind of configuration:

fn init_console_log(
    tracer: opentelemetry_sdk::trace::Tracer,
) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
    let telemetry = tracing_opentelemetry::layer().with_tracer(tracer);

    let subscriber = tracing_subscriber::registry::Registry::default()
        .with(tracing_subscriber::fmt::layer())
        .with(tracing_subscriber::EnvFilter::from_str(
            "gcloud_sdk=debug",
        )?)
        .with(telemetry);

    tracing::subscriber::set_global_default(subscriber)?;

    Ok(())
}

fn init_stackdriver_log(
    gcp_project_id: &str,
    tracer: opentelemetry_sdk::trace::Tracer,
) -> Result<(), BoxedError> {
    let telemetry_layer = tracing_opentelemetry::layer().with_tracer(tracer);

    let stackdriver_layer = tracing_stackdriver::layer().with_cloud_trace(
        tracing_stackdriver::CloudTraceConfiguration {
            project_id: gcp_project_id.to_string(),
        },
    );

    let subscriber = tracing_subscriber::Registry::default()
        .with(telemetry_layer)
        .with(stackdriver_layer)
        .with(tracing_subscriber::EnvFilter::from_str(
            "gcloud_sdk=debug",
        )?);
    tracing::subscriber::set_global_default(subscriber)
        .expect("Could not set up global logger");

    Ok(())
}

async fn init_tracing(app_mode: &GlobalAppMode,
                      tracer: GcpCloudTraceExporter,
                      gcp_project_id: &str) -> Result<(), BoxedError> {
    match app_mode {
        GlobalAppMode::Production => init_stackdriver_log(gcp_project_id, tracer),
        GlobalAppMode::Development => init_console_log(tracer),
    }
}

#[tokio::main]
async fn main() -> Result<(), BoxedError> {
    let gcp_project_id = "my-gcp-project-id";
    let exporter = GcpCloudTraceExporterBuilder::new(gcp_project_id.into());
    let tracer_provider = gcp_trace_exporter.create_provider().await?;
    let tracer: opentelemetry_sdk::trace::Tracer = gcp_trace_exporter.install(&tracer_provider).await?;
    let app_mode = GlobalAppMode::Development;

    opentelemetry::global::set_tracer_provider(tracer_provider.clone());
    
    init_tracing(&app_mode, tracer, gcp_project_id).await?;
    
    // ...

    tracer_provider.shutdown()?;
}

TLS related features

Cargo provides support for different TLS features for dependencies:

• tls-roots: default feature to support native TLS roots
• tls-webpki-roots: feature to switch to webpki crate roots

Licence

Apache Software License (ASL)

Author

Abdulla Abdurakhmanov