tracing-gcloud-layer

A robust and configurable tracing layer for Rust, delivering logs from the tracing ecosystem directly to Google Cloud Logging (Stackdriver).

🚀 Features

• Seamless integration with Rust’s tracing ecosystem.
• Structured logs delivered to Google Cloud Logging (Stackdriver) using service account authentication.
• Asynchronous, batched log delivery for improved efficiency.
• Log formatting and enrichment customizable via the LogMapper trait.
• Basic support for trace ID and severity metadata propagation.

📦 Installation

Add to your Cargo.toml:

cargo add tracing-gcloud-layer

🛠️ Quickstart

1. Generate a Google Cloud service account with the "Logs Writer" role and download the JSON key.

2. Initialize the tracing layer:

use tracing_gcloud_layer::DefaultGCloudLayerConfigBuilder;
use tracing_subscriber::Registry;

let (layer, _runtime) = DefaultGCloudLayerConfigBuilder::default()
    .log_name("my-service")
    .logger_credential(include_bytes!("../gcp-service-account.json"))
    .build()
    .expect("Invalid config")
    .build_layer();

tracing_subscriber::registry()
    .with(layer)
    .init();

3. Emit logs in your application:

tracing::info!(user_id = 42, "User logged in");

Logs will appear in Google Cloud Logging under the configured log name

⚙️ Configuration

• log_name: Log stream name in GCP (e.g., "stdout", "my-app").
• logger_credential: Service account credentials (as bytes).
• config: Batching, timeouts, and writer options.
• log_mapper: Plug in your own LogMapper to customize log transformation.

Example: Custom Log Mapper

use tracing_gcloud_layer::{GCloudLayerConfigBuilder, LogContext, LogMapper};

#[derive(Clone, Default)]
pub struct CustomLogMapper;

impl LogMapper for CustomLogMapper {
    fn map(&self, context: LogContext, log_entry: serde_json::Value) -> serde_json::Value {
        todo!("Custom mapping logic here")
    }
}

let (layer, _runtime) = GCloudLayerConfigBuilder::<CustomLogMapper>::default()
    .log_name("custom-logs")
    .logger_credential(include_bytes!("../gcp.json"))
    .log_mapper(CustomLogMapper)
    .build()
    .expect("Invalid config")
    .build_layer();