axum-insights

An Azure Application Insights exporter for axum via tracing.

Usage

This library is meant to be used as a layer for axum. It will automatically instrument your axum application, and send telemetry to Azure Application Insights. As the ecosystem matures, more features will be added.

Example

The following example is a "complete" example, which means that it includes all of the optional features of this library.

```rust use serde::{Serialize, Deserialize}; use axum::Router; use axuminsights::AppInsights; use axuminsights::AppInsightsError; use tracing_subscriber::filter::LevelFilter; use std::collections::HashMap;

[derive(Default, Serialize, Deserialize, Clone)]

struct WebError { message: String, }

impl AppInsightsError for WebError { fn message(&self) -> Option { Some(self.message.clone()) }

fn backtrace(&self) -> Option<String> {
    None
}

}

let telemetrylayer = AppInsights::default() .withconnectionstring(None) // Accepts an optional connection string. If None, then no telemetry is sent. .withserviceconfig("namespace", "name") // Sets the service namespace and name. Default is empty. .withclient(reqwest::Client::new()) // Sets the HTTP client to use for sending telemetry. Default is reqwest async client. .withsamplerate(1.0) // Sets the sample rate for telemetry. Default is 1.0. .withminimumlevel(LevelFilter::INFO) // Sets the minimum level for telemetry. Default is INFO. .withsubscriber(tracingsubscriber::registry()) // Sets the subscriber to use for telemetry. Default is a new subscriber. .withruntime(opentelemetry::runtime::Tokio) // Sets the runtime to use for telemetry. Default is Tokio. .withcatchpanic(true) // Sets whether or not to catch panics, and emit a trace for them. Default is false. .withfieldmapper(|parts| { // Sets a function to extract extra fields from the request. Default is no extra fields. let mut map = HashMap::new(); map.insert("extrafield".toowned(), "extravalue".toowned()); map }) .withpanicmapper(|panic| { // Sets a function to extract extra fields from a panic. Default is a default error. (500, WebError { message: panic }) }) .witherrortype::() .buildandsetglobal_default() .unwrap() .layer();

// You likely will not need to specify Router<()> in your implementation. This is just for the example. let app: Router<()> = Router::new() // ... .layer(telemetry_layer);

// Then, in a handler, you would use the tracing macros to emit telemetry.

use axum::response::IntoResponse; use axum::Json; use tracing::{instrument, debug, error, info, warn};

[instrument]

async fn handler(Json(body): Json) -> Result { debug!("Debug message"); info!("Info message"); warn!("Warn message"); error!("Error message");

if body == "error" {
    return Err(WebError { message: "Error".to_owned() });
}

Ok(())

} ```

Acknowledgements

This library depends on individual efforts of other maintainers such as: * opentelemetry-application-insights by @frigus02. * appinsights-rs by @dmolokanov.

Test

bash cargo test --features web