tracing-stackdriver

A tracing Subscriber for communicating Stackdriver-formatted logs

tracing is a scoped, structured logging and diagnostic system based on emitting Events in the context of potentially-nested Spans across asynchronous await points. These properties make tracing ideal for use with Google Cloud Operations Suite structured logging (formerly Stackdriver). This crate provides a Layer for use with a tracing Registry that formats tracing Spans and Events into properly-structured JSON for consumption by Google Operations Logging through the jsonPayload field. This includes the following behaviors and enhancements:

1. rfc3339-formatted timestamps for all Events
2. severity (in LogSeverity format) derived from tracing Level
3. target derived from the Event target Metadata
4. Span name and custom fields included under a span key
5. automatic nesting of http_request.-prefixed event fields
6. automatic camelCase-ing of all field keys (e.g. http_request -> httpRequest)

Examples

Basic setup:

```rust use tracingsubscriber::{layer::SubscriberExt, Registry}; use tracingstackdriver::Stackdriver;

fn main() { let stackdriver = Stackdriver::default(); // writes to std::io::Stdout let subscriber = Registry::default().with(stackdriver);

tracing::subscriber::set_global_default(subscriber).expect("Could not set up global logger");

} ```

Custom write location:

```rust use tracingsubscriber::{layer::SubscriberExt, Registry}; use tracingstackdriver::Stackdriver;

fn main() { let makewriter = || std::io::Stderr; let stackdriver = Stackdriver::withwriter(make_writer); // writes to std::io::Stderr let subscriber = Registry::default().with(stackdriver);

tracing::subscriber::set_global_default(subscriber).expect("Could not set up global logger");

} ```

With httpRequest fields:

See all available fields here

```rust // requires working global setup (see above examples)

use hyper::Request;

fn handle_request(request: Request) { let method = &request.method(); let uri = &request.uri();

tracing::info!( httprequest.requestmethod = %method, httprequest.requesturl = %uri, "Request received" );

// jsonPayload formatted as: // { // "time": "some-timestamp" // "severity": "INFO", // "httpRequest": { // "requestMethod": "GET", // "requestUrl": "/some/url/from/request" // }, // "message": "Request received" // } } ```

Roadmap:

1. type-safe http_requests derived from Google's REST v2 spec
2. distributing tracing data in Cloud Trace format