Tracing with axum/tower_http via layer

Cargo.lock

@@ -814,11 +814,9 @@ dependencies = [
  "minijinja",
  "notify",
  "pathdiff",
- "redact",
  "serde",
  "thiserror",
  "tokio",
- "tower",
  "tower-http",
  "tower-livereload",
  "tracing",
@@ -1123,15 +1121,6 @@ dependencies = [
  "proc-macro2",
 ]
 
-[[package]]
-name = "redact"
-version = "0.1.9"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b7301863b5e5486c9f18320ccc1aedce9a5fdf3056ae89fa021933d6f054430f"
-dependencies = [
- "serde",
-]
-
 [[package]]
 name = "redox_syscall"
 version = "0.4.1"

Cargo.toml

@@ -19,20 +19,18 @@ panic = "abort"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-axum = { version = "0.7.5", features = ["macros", "tokio"] }
-clap = { version = "4.5.4", features = ["derive"] }
+axum = { version = "0.7.5", features = ["macros", "tokio", "tracing"] }
+clap = { version = "4.5.4", features = ["derive", "env"] }
 color-eyre = "0.6.3"
 config = "0.14.0"
 futures = "0.3.30"
 minijinja = { version = "2.0.1", features = ["loader"] }
 notify = "6.1.1"
 pathdiff = "0.2.1"
-redact = { version = "0.1.9", features = ["serde"] }
 serde = "1.0.201"
 thiserror = "1.0.60"
 tokio = { version = "1.37.0", features = ["full"] }
-tower = "0.4.13"
-tower-http = { version = "0.5.2", features = ["fs"] }
+tower-http = { version = "0.5.2", features = ["fs", "trace"] }
 tower-livereload = "0.9.2"
 tracing = "0.1.40"
 tracing-subscriber = { version = "0.3.18", features = ["env-filter"] }

src/cli.rs

@@ -1,4 +1,4 @@
-use crate::{prelude::*, router::NewRouterError};
+use crate::{observe, prelude::*, router::NewRouterError};
 use prelude::*;
 use thiserror::Error;
 
@@ -13,6 +13,9 @@ mod prelude {
 pub struct Cli {
     #[command(subcommand)]
     command: Commands,
+
+    #[arg(global = true, long, value_enum, default_value = "info,lyrs=trace")]
+    log_env_filter: String,
 }
 
 #[derive(Subcommand)]
@@ -64,10 +67,14 @@ pub fn cli() -> Cli {
 pub enum ExecError {
     #[error("run error: {0}")]
     Run(#[from] RunError),
+
+    #[error("{0}")]
+    Eyre(#[from] color_eyre::Report),
 }
 
 impl Cli {
     pub async fn exec(self) -> Result<(), ExecError> {
+        observe::setup_logging(&self.log_env_filter)?;
         match self.command {
             Commands::Run(args) => Ok(args.run().await?),
         }

src/observe.rs

@@ -1,11 +1,23 @@
-pub fn setup_logging() {
-    color_eyre::install().expect("Failed to install color_eyre");
+use crate::prelude::*;
+
+pub fn setup_logging(env_filter: &str) -> Result<(), color_eyre::Report> {
+    color_eyre::install()?;
 
     let filter = tracing_subscriber::EnvFilter::builder()
         .with_default_directive(<tracing_subscriber::filter::Directive>::from(
             tracing::level_filters::LevelFilter::TRACE,
         ))
-        .parse_lossy("info,lyrs=trace");
+        .parse_lossy(env_filter);
 
     tracing_subscriber::fmt().with_env_filter(filter).init();
+
+    let filter = tracing_subscriber::EnvFilter::builder()
+        .with_default_directive(<tracing_subscriber::filter::Directive>::from(
+            tracing::level_filters::LevelFilter::TRACE,
+        ))
+        .parse_lossy(env_filter);
+
+    info!("{filter}");
+
+    Ok(())
 }

src/router.rs

@@ -1,3 +1,5 @@
+use std::time::Duration;
+
 use crate::{
     file_watcher::FileWatcher,
     prelude::*,
@@ -5,16 +7,19 @@ use crate::{
     static_files,
 };
 use axum::{
-    extract::State,
-    http::StatusCode,
+    body::Bytes,
+    extract::{MatchedPath, State},
+    http::{HeaderMap, Request, Response, StatusCode},
     response::{Html, IntoResponse},
     routing::get,
     Router,
 };
 use minijinja::context;
+use tower_http::{classify::ServerErrorsFailureClass, trace::TraceLayer};
 use tower_livereload::LiveReloadLayer;
 
 use thiserror::Error;
+use tracing::{info_span, Span};
 
 #[derive(Error, Debug)]
 pub enum NewRouterError {
@@ -71,6 +76,52 @@ pub async fn router(
         .route("/", get(index))
         .route("/about", get(about))
         .nest_service("/static", static_file_service)
+        // `TraceLayer` is provided by tower-http so you have to add that as a dependency.
+        // It provides good defaults but is also very customizable.
+        //
+        // See https://docs.rs/tower-http/0.1.1/tower_http/trace/index.html for more details.
+        //
+        // If you want to customize the behavior using closures here is how.
+        .layer(
+            TraceLayer::new_for_http()
+                .make_span_with(|request: &Request<_>| {
+                    // Log the matched route's path (with placeholders not filled in).
+                    // Use request.uri() or OriginalUri if you want the real path.
+                    let matched_path = request
+                        .extensions()
+                        .get::<MatchedPath>()
+                        .map(MatchedPath::as_str);
+
+                    info_span!(
+                        "http_request",
+                        method = ?request.method(),
+                        matched_path,
+                        some_other_field = tracing::field::Empty,
+                    )
+                })
+                .on_request(|_request: &Request<_>, _span: &Span| {
+                    // You can use `_span.record("some_other_field", value)` in one of these
+                    // closures to attach a value to the initially empty field in the info_span
+                    // created above.
+                })
+                .on_response(|response: &Response<_>, latency: Duration, _span: &Span| {
+                    trace!("on_response: {response:?} in {latency:?}");
+                })
+                .on_body_chunk(|_chunk: &Bytes, _latency: Duration, _span: &Span| {
+                    // ...
+                })
+                .on_eos(
+                    |_trailers: Option<&HeaderMap>, _stream_duration: Duration, _span: &Span| {
+                        // ...
+                    },
+                )
+                .on_failure(
+                    |error: ServerErrorsFailureClass, latency: Duration, _span: &Span| {
+                        error!("on_failure: {error:?} in {latency:?}");
+                        // ...
+                    },
+                ),
+        )
         .with_state(state.clone());
 
     if let Some(lr) = live_reload_layer {
@@ -82,6 +133,7 @@ pub async fn router(
     Ok((result, watchers))
 }
 
+#[instrument(skip(state))]
 async fn index(State(state): State<AppState>) -> ReqResult<Html<String>> {
     Ok(Html(
         state
@@ -90,6 +142,8 @@ async fn index(State(state): State<AppState>) -> ReqResult<Html<String>> {
             .await?,
     ))
 }
+
+#[instrument(skip(state))]
 async fn about(State(state): State<AppState>) -> ReqResult<Html<String>> {
     Ok(Html(
         state