Make logging level configurable

Read initial log level from config file if present. Once the server is
running the level can be changed via a POST request to /loglevel/{level}
where level is one of info, debug or trace.

Author: tpoliaw

src/config.rs

@@ -10,6 +10,8 @@ pub struct GlazedConfig {
     pub bind_address: SocketAddr,
     pub public_address: Option<Url>,
     pub tiled_client: TiledClientConfig,
+    #[serde(default)]
+    pub log_level: LogLevel,
 }
 impl GlazedConfig {
     pub fn from_file(path: &Path) -> Result<Self, ConfigError> {
@@ -24,6 +26,7 @@ impl GlazedConfig {
             tiled_client: TiledClientConfig {
                 address: Url::parse("http://localhost:8000").expect("Static URL is valid"),
             },
+            log_level: LogLevel::Info,
         }
     }
 }
@@ -32,3 +35,24 @@ impl GlazedConfig {
 pub struct TiledClientConfig {
     pub address: Url,
 }
+
+#[derive(Debug, Default, Deserialize, Clone, Copy)]
+pub enum LogLevel {
+    #[default]
+    #[serde(alias = "info")]
+    Info,
+    #[serde(alias = "debug")]
+    Debug,
+    #[serde(alias = "trace")]
+    Trace,
+}
+
+impl From<LogLevel> for tracing::level_filters::LevelFilter {
+    fn from(value: LogLevel) -> Self {
+        match value {
+            LogLevel::Info => Self::INFO,
+            LogLevel::Debug => Self::DEBUG,
+            LogLevel::Trace => Self::TRACE,
+        }
+    }
+}

src/main.rs

@@ -1,4 +1,5 @@
 use async_graphql::{EmptyMutation, EmptySubscription, Schema};
+use axum::extract::Path;
 use axum::http::StatusCode;
 use axum::response::{Html, IntoResponse};
 use axum::routing::{get, post};
@@ -18,17 +19,24 @@ use serde_json::json;
 use tokio::select;
 use tokio::signal::unix::{SignalKind, signal};
 use tracing::info;
+use tracing::level_filters::LevelFilter;
+use tracing_subscriber::layer::SubscriberExt as _;
+use tracing_subscriber::util::SubscriberInitExt;
+use tracing_subscriber::{Registry, fmt, reload};
 use url::Url;
 
 use crate::clients::TiledClient;
-use crate::config::GlazedConfig;
+use crate::config::{GlazedConfig, LogLevel};
 use crate::handlers::{download_handler, graphiql_handler, graphql_handler};
 use crate::model::TiledQuery;
 
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
-    let subscriber = tracing_subscriber::FmtSubscriber::new();
-    tracing::subscriber::set_global_default(subscriber)?;
+    let (filter, filter_reload) = reload::Layer::new(LevelFilter::INFO);
+    tracing_subscriber::registry()
+        .with(filter)
+        .with(fmt::Layer::default())
+        .init();
 
     let cli = Cli::init();
     let config;
@@ -41,15 +49,21 @@ async fn main() -> Result<(), Box<dyn std::error::Error>> {
         info!("Using default config");
         config = GlazedConfig::default();
     }
+    filter_reload
+        .modify(|f| *f = config.log_level.into())
+        .unwrap();
     match cli.command {
-        Commands::Serve => serve(config).await,
+        Commands::Serve => serve(config, filter_reload).await,
     }
 }
 
 #[derive(Clone)]
 pub struct RootAddress(Url);
 
-async fn serve(config: GlazedConfig) -> Result<(), Box<dyn std::error::Error>> {
+async fn serve(
+    config: GlazedConfig,
+    reload: reload::Handle<LevelFilter, Registry>,
+) -> Result<(), Box<dyn std::error::Error>> {
     let client = TiledClient::new(config.tiled_client.address);
     let public_address = config
         .public_address
@@ -72,6 +86,12 @@ async fn serve(config: GlazedConfig) -> Result<(), Box<dyn std::error::Error>> {
             get(Json(json!({"version": env!("CARGO_PKG_VERSION")}))),
         )
         .route("/asset/{run}/{stream}/{det}/{id}", get(download_handler))
+        .route(
+            "/loglevel/{level}",
+            post(|level: Path<LogLevel>| async move {
+                reload.clone().modify(|f| *f = level.0.into()).unwrap();
+            }),
+        )
         .with_state(client)
         .fallback((
             StatusCode::NOT_FOUND,

src/model.rs

@@ -10,7 +10,7 @@ use std::collections::HashMap;
 
 use async_graphql::{Context, Object, Result, Union};
 use serde_json::Value;
-use tracing::{info, instrument};
+use tracing::instrument;
 
 use crate::RootAddress;
 use crate::clients::{ClientError, TiledClient};
@@ -174,7 +174,6 @@ impl TableData {
             .map(|s| s.as_str())
             .collect::<Vec<_>>()
             .join("/");
-        info!("path: {:?}", p);
 
         let table_data = client.table_full(&p, columns, headers).await?;
         Ok(table_data)