History

Robert Collins 07d154cadf Custom otel names (#65 ) * Breaking change(macros): require explicit name for tracing middleware Closes: #52 This is suggested by the Opentelemetry spec, which requires "Therefore, HTTP client spans SHOULD be using conservative, low cardinality names formed from the available parameters of an HTTP request, such as "HTTP {METHOD_NAME}". Instrumentation MUST NOT default to using URI path as span name, but MAY provide hooks to allow custom logic to override the default span name. " * Permit customisation of otel span names via OtelName		2022-11-07 13:07:23 +00:00
..
src	Custom otel names (#65 )	2022-11-07 13:07:23 +00:00
CHANGELOG.md	Custom otel names (#65 )	2022-11-07 13:07:23 +00:00
Cargo.toml	Opentelemetry 0.18 (#58 )	2022-09-20 16:07:32 +03:00
README.md	Add missing dep in reqwest-tracing README (#61 )	2022-10-05 14:56:46 +01:00

README.md

reqwest-tracing

Opentracing middleware implementation for reqwest-middleware.

Overview

Attach TracingMiddleware to your client to automatically trace HTTP requests:

# Cargo.toml
# ...
[dependencies]
opentelemetry = "0.18"
reqwest = "0.11"
reqwest-middleware = "0.1.1"
reqwest-retry = "0.1.1"
reqwest-tracing = { version = "0.3.1", features = ["opentelemetry_0_18"] }
tokio = { version = "1.12.0", features = ["macros", "rt-multi-thread"] }
tracing = "0.1"
tracing-opentelemetry = "0.18"
tracing-subscriber = "0.3"
task-local-extensions = "0.1.0"

use reqwest_tracing::{default_on_request_end, reqwest_otel_span, ReqwestOtelSpanBackend, TracingMiddleware};
use opentelemetry::sdk::export::trace::stdout;
use reqwest::{Request, Response};
use reqwest_middleware::{ClientBuilder, Result};
use std::time::Instant;
use task_local_extensions::Extensions;
use tracing::Span;
use tracing_subscriber::layer::SubscriberExt;
use tracing_subscriber::Registry;

pub struct TimeTrace;

impl ReqwestOtelSpanBackend for TimeTrace {
    fn on_request_start(req: &Request, extension: &mut Extensions) -> Span {
        extension.insert(Instant::now());
        reqwest_otel_span!(req, time_elapsed = tracing::field::Empty)
    }

    fn on_request_end(span: &Span, outcome: &Result<Response>, extension: &mut Extensions) {
        let time_elapsed = extension.get::<Instant>().unwrap().elapsed().as_millis() as i64;
        default_on_request_end(span, outcome);
        span.record("time_elapsed", &time_elapsed);
    }
}

#[tokio::main]
async fn main() {
    let tracer = stdout::new_pipeline().install_simple();
    let telemetry = tracing_opentelemetry::layer().with_tracer(tracer);
    let subscriber = Registry::default().with(telemetry);
    tracing::subscriber::set_global_default(subscriber).unwrap();

    run().await;
}

async fn run() {
    let client = ClientBuilder::new(reqwest::Client::new())
        .with(TracingMiddleware::<TimeTrace>::new())
        .build();

    client.get("https://truelayer.com").send().await.unwrap();
}

$ cargo run
SpanData { span_context: SpanContext { trace_id: ...

See the tracing crate for more information on how to set up a tracing subscriber to make use of the spans.

How to install

Add reqwest-tracing to your dependencies. Optionally enable opentelemetry integration by enabling an opentelemetry version feature:

[dependencies]
# ...
reqwest-tracing = { version = "0.3.1", features = ["opentelemetry_0_18"] }

Available opentelemetry features are opentelemetry_0_18, opentelemetry_0_17, opentelemetry_0_16, opentelemetry_0_15, opentelemetry_0_14 and opentelemetry_0_13.

License

^{Licensed under either of Apache License, Version
2.0 or MIT license at your option.}
_{Unless you explicitly state otherwise, any contribution intentionally submitted
for inclusion in the work by you, as defined in the Apache-2.0 license, shall be
dual licensed as above, without any additional terms or conditions.}