Improve logging in the Rust part (#1215)

* `agama-web-server` writes now to the stdout if it is not connected to
journald.
* `agama-dbus-server` uses
[tracing](https://github.com/tokio-rs/tracing).
* The stdout logger now includes the file/line. They were already
included in the journal logs.

```
2024-05-15T15:30:42.816878Z  WARN agama_server::network::nm::client: agama-server/src/network/nm/client.rs:155: Ignoring network device on path /org/freedesktop/NetworkManager/Devices/1
2024-05-15T15:30:42.845629Z  INFO agama_server::web::service: agama-server/src/web/service.rs:91: Serving static files from /usr/share/agama/web_ui
2024-05-15T15:30:42.901972Z  INFO agama_web_server: agama-server/src/agama-web-server.rs:253: Starting Agama web server at 0.0.0.0:443
2024-05-15T15:30:42.901993Z  INFO agama_web_server: agama-server/src/agama-web-server.rs:253: Starting Agama web server at 0.0.0.0:80
```

rust/agama-server/Cargo.toml

@@ -11,8 +11,6 @@ anyhow = "1.0"
 agama-locale-data = { path = "../agama-locale-data" }
 agama-lib = { path = "../agama-lib" }
 log = "0.4"
-simplelog = "0.12.1"
-systemd-journal-logger = "1.0"
 zbus = { version = "3", default-features = false, features = ["tokio"] }
 zbus_macros = "3"
 uuid = { version = "1.3.4", features = ["v4"] }
@@ -53,7 +51,10 @@ openssl = "0.10.64"
 hyper = "1.2.0"
 hyper-util = "0.1.3"
 tokio-openssl = "0.6.4"
-futures-util = { version = "0.3.30", default-features = false, features = ["alloc"] }
+futures-util = { version = "0.3.30", default-features = false, features = [
+  "alloc",
+] }
+libsystemd = "0.7.0"
 
 [[bin]]
 name = "agama-dbus-server"

rust/agama-server/src/agama-dbus-server.rs

@@ -1,11 +1,11 @@
 use agama_server::{
     l10n::{self, helpers},
+    logs::init_logging,
     questions,
 };
 
 use agama_lib::connection_to;
 use anyhow::Context;
-use log::{self, LevelFilter};
 use std::future::pending;
 
 const ADDRESS: &str = "unix:path=/run/agama/bus";
@@ -14,23 +14,7 @@ const SERVICE_NAME: &str = "org.opensuse.Agama1";
 #[tokio::main]
 async fn main() -> Result<(), Box<dyn std::error::Error>> {
     let locale = helpers::init_locale()?;
-
-    // be smart with logging and log directly to journal if connected to it
-    if systemd_journal_logger::connected_to_journal() {
-        // unwrap here is intentional as we are sure no other logger is active yet
-        systemd_journal_logger::JournalLog::default()
-            .install()
-            .unwrap();
-        log::set_max_level(LevelFilter::Info); // log only info for journal logger
-    } else {
-        simplelog::TermLogger::init(
-            LevelFilter::Info, // lets use info, trace provides too much output from libraries
-            simplelog::Config::default(),
-            simplelog::TerminalMode::Stderr, // only stderr output for easier filtering
-            simplelog::ColorChoice::Auto,
-        )
-        .unwrap(); // unwrap here as we are sure no other logger active
-    }
+    init_logging().context("Could not initialize the logger")?;
 
     let connection = connection_to(ADDRESS)
         .await

rust/agama-server/src/agama-web-server.rs

@@ -10,6 +10,7 @@ use std::{
 use agama_lib::connection_to;
 use agama_server::{
     l10n::helpers,
+    logs::init_logging,
     web::{self, generate_token, run_monitor},
 };
 use anyhow::Context;
@@ -27,7 +28,6 @@ use openssl::ssl::{Ssl, SslAcceptor, SslFiletype, SslMethod};
 use tokio::sync::broadcast::channel;
 use tokio_openssl::SslStream;
 use tower::Service;
-use tracing_subscriber::prelude::*;
 use utoipa::OpenApi;
 
 const DEFAULT_WEB_UI_DIR: &str = "/usr/share/agama/web_ui";
@@ -292,8 +292,7 @@ async fn start_server(address: String, service: Router, ssl_acceptor: SslAccepto
 /// Start serving the API.
 /// `options`: command-line arguments.
 async fn serve_command(args: ServeArgs) -> anyhow::Result<()> {
-    let journald = tracing_journald::layer().context("could not connect to journald")?;
-    tracing_subscriber::registry().with(journald).init();
+    init_logging().context("Could not initialize the logger")?;
 
     let (tx, _) = channel(16);
     run_monitor(tx.clone()).await?;

rust/agama-server/src/lib.rs

@@ -2,6 +2,7 @@ pub mod cert;
 pub mod dbus;
 pub mod error;
 pub mod l10n;
+pub mod logs;
 pub mod manager;
 pub mod network;
 pub mod questions;

rust/agama-server/src/logs.rs

@@ -0,0 +1,23 @@
+//! Functions to work with logs.
+
+use anyhow::Context;
+use libsystemd::logging;
+use tracing_subscriber::prelude::*;
+
+/// Initializes the logging mechanism.
+///
+/// It is based on [Tracing](https://github.com/tokio-rs/tracing), part of the Tokio ecosystem.
+pub fn init_logging() -> anyhow::Result<()> {
+    if logging::connected_to_journal() {
+        let journald = tracing_journald::layer().context("could not connect to journald")?;
+        tracing_subscriber::registry().with(journald).init();
+    } else {
+        let subscriber = tracing_subscriber::fmt()
+            .with_file(true)
+            .with_line_number(true)
+            .compact()
+            .finish();
+        tracing::subscriber::set_global_default(subscriber)?;
+    }
+    Ok(())
+}

rust/package/agama.changes

@@ -1,3 +1,13 @@
+-------------------------------------------------------------------
+Wed May 15 15:21:30 UTC 2024 - Imobach Gonzalez Sosa <igonzalezsosa@suse.com>
+
+- Improve logging in the D-Bus and web servers
+  (gh#openSUSE/agama#1215):
+  - Write to the stdout if they are not connected to
+    systemd-journald.
+  - The stdout logger includes the file/line (it was already
+    included when logging to systemd-journald).
+
 -------------------------------------------------------------------
 Wed May 15 14:08:26 UTC 2024 - Imobach Gonzalez Sosa <igonzalezsosa@suse.com>