[PATCH proxmox 1/5] log: replace per layer filtering by one global filter

[Thomas Ellmenreich <t.ellmenreich@proxmox.com>]

Instead of filtering with the global filter on every layer, provide one
global filter once, as described here: [0]

This is also in preparation for filters that either have to be cloned or
cannot be cloned at all, like EnvFilters* [1].

* EnvFilter can be cloned from tracing_subscriber version 0.3.20 onwards.

[0]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/layer/index.html#global-filtering
[1]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/filter/struct.EnvFilter.html

Signed-off-by: Thomas Ellmenreich <t.ellmenreich@proxmox.com>
---
 proxmox-log/src/builder.rs            | 48 +++++++++------------------
 proxmox-log/src/pve_task_formatter.rs |  2 +-
 2 files changed, 17 insertions(+), 33 deletions(-)

diff --git a/proxmox-log/src/builder.rs b/proxmox-log/src/builder.rs
index 6fcf1cc9..3108ea29 100644
--- a/proxmox-log/src/builder.rs
+++ b/proxmox-log/src/builder.rs
@@ -1,8 +1,9 @@
 use tracing::Level;
 use tracing::Metadata;
 use tracing::level_filters::LevelFilter;
-use tracing_log::{AsLog, LogTracer};
+use tracing_log::LogTracer;
 use tracing_subscriber::Layer;
+use tracing_subscriber::Registry;
 use tracing_subscriber::layer::Context;
 use tracing_subscriber::layer::Filter;
 use tracing_subscriber::layer::SubscriberExt;
@@ -55,9 +56,7 @@ impl<S> Filter<S> for NoWorkerTask {
 /// ```
 pub struct Logger {
     global_log_level: LevelFilter,
-    layer: Vec<
-        Box<dyn tracing_subscriber::Layer<tracing_subscriber::Registry> + Send + Sync + 'static>,
-    >,
+    layer: Vec<Box<dyn Layer<Registry> + Send + Sync + 'static>>,
 }
 
 impl Logger {
@@ -76,11 +75,7 @@ impl Logger {
     ///
     /// If the journal cannot be opened, print to stderr instead.
     pub fn journald(mut self) -> Logger {
-        self.layer.push(
-            journald_or_stderr_layer()
-                .with_filter(self.global_log_level)
-                .boxed(),
-        );
+        self.layer.push(journald_or_stderr_layer().boxed());
         self
     }
 
@@ -90,12 +85,8 @@ impl Logger {
     /// no LogContext exists – which means we are not in a PBS workertask – or the level of the
     /// log message is 'ERROR'.
     pub fn journald_on_no_workertask(mut self) -> Logger {
-        self.layer.push(
-            journald_or_stderr_layer()
-                .with_filter(NoWorkerTask)
-                .with_filter(self.global_log_level)
-                .boxed(),
-        );
+        self.layer
+            .push(journald_or_stderr_layer().with_filter(NoWorkerTask).boxed());
         self
     }
 
@@ -103,8 +94,7 @@ impl Logger {
     ///
     /// Check if a LogContext exists and if it does, print to the corresponding task log file.
     pub fn tasklog_pbs(mut self) -> Logger {
-        self.layer
-            .push(TasklogLayer {}.with_filter(self.global_log_level).boxed());
+        self.layer.push(TasklogLayer.boxed());
         self
     }
 
@@ -112,11 +102,7 @@ impl Logger {
     ///
     /// Prints all the events to stderr with the compact format (no level, no timestamp).
     pub fn stderr(mut self) -> Logger {
-        self.layer.push(
-            plain_stderr_layer()
-                .with_filter(self.global_log_level)
-                .boxed(),
-        );
+        self.layer.push(plain_stderr_layer().boxed());
         self
     }
 
@@ -126,12 +112,8 @@ impl Logger {
     /// triggered if no workertask could be found (no LogContext exists) or the event level is
     /// `ERROR`.
     pub fn stderr_on_no_workertask(mut self) -> Logger {
-        self.layer.push(
-            plain_stderr_layer()
-                .with_filter(NoWorkerTask)
-                .with_filter(self.global_log_level)
-                .boxed(),
-        );
+        self.layer
+            .push(plain_stderr_layer().with_filter(NoWorkerTask).boxed());
         self
     }
 
@@ -141,9 +123,8 @@ impl Logger {
     /// e.g.: `DEBUG: event message`.
     pub fn stderr_pve(mut self) -> Logger {
         let layer = tracing_subscriber::fmt::layer()
-            .event_format(PveTaskFormatter {})
+            .event_format(PveTaskFormatter)
             .with_writer(std::io::stderr)
-            .with_filter(self.global_log_level)
             .boxed();
         self.layer.push(layer);
         self
@@ -153,10 +134,13 @@ impl Logger {
     ///
     /// Also configures the `LogTracer` which will convert all `log` events to tracing events.
     pub fn init(self) -> Result<(), anyhow::Error> {
-        let registry = tracing_subscriber::registry().with(self.layer);
+        let registry = tracing_subscriber::registry()
+            .with(self.layer)
+            .with(self.global_log_level);
+
         tracing::subscriber::set_global_default(registry)?;
 
-        LogTracer::init_with_filter(self.global_log_level.as_log())?;
+        LogTracer::init()?;
         Ok(())
     }
 }
diff --git a/proxmox-log/src/pve_task_formatter.rs b/proxmox-log/src/pve_task_formatter.rs
index e9866a4b..12bc33c8 100644
--- a/proxmox-log/src/pve_task_formatter.rs
+++ b/proxmox-log/src/pve_task_formatter.rs
@@ -8,7 +8,7 @@ use tracing_subscriber::registry::LookupSpan;
 /// This custom formatter outputs logs as they are visible in the PVE task log.
 ///
 /// e.g.: "DEBUG: sample message"
-pub struct PveTaskFormatter {}
+pub struct PveTaskFormatter;
 
 impl<C, N> FormatEvent<C, N> for PveTaskFormatter
 where
-- 
2.47.3