Macro make_request_spanner 

macro_rules! make_request_spanner {
    ($fn:ident($name:literal, $level:expr)) => { ... };
    ($fn:ident($name:literal, $level:expr, $($fields:tt)*)) => { ... };
}

Declares fn function compatible with MakeSpan using provided parameters

Span fields

Following fields are declared when span is created:

• http.method
• http.url
• http.request_id - Inherited from request ‘X-Request-Id’ or random uuid
• http.user_agent - Only populated if user agent header is present
• http.version
• http.headers - Optional. Populated if more than 1 header specified via layer config
• protocol - Either http or grpc depending on content-type
• http.client.ip - Optionally added if IP extractor is specified via layer config
• http.status_code - Semantics of this code depends on protocol
• error.message - Populated with Display content of the error, returned by underlying service, after processing request.

Usage

use tower_http_tracing::make_request_spanner;

make_request_spanner!(make_my_request_span("my_request", tracing::Level::INFO));
make_request_spanner!(make_my_service_request_span("my_request", tracing::Level::INFO, service_name = "<your name>"));

let span = make_my_request_span();
span.record("http.url", "I can override span field");