From ba4009170bcfa3ecaeb182ef1744aa9c7ebe8508 Mon Sep 17 00:00:00 2001
From: Michael-F-Bryan <michael@wasmer.io>
Date: Fri, 9 Jun 2023 15:26:11 +0800
Subject: [PATCH] Disable logging unless the $RUST_LOG variable is set

---
 Cargo.lock                  |  1 -
 lib/cli/Cargo.toml          |  1 -
 lib/cli/src/cli.rs          |  2 ++
 lib/cli/src/commands/run.rs |  5 -----
 lib/cli/src/logging.rs      | 20 ++++----------------
 5 files changed, 6 insertions(+), 23 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 03d32af84e7..b8aeb1b7c6f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -5633,7 +5633,6 @@ dependencies = [
  "cfg-if 1.0.0",
  "chrono",
  "clap 4.3.2",
- "clap-verbosity-flag",
  "colored 2.0.0",
  "dialoguer",
  "dirs",
diff --git a/lib/cli/Cargo.toml b/lib/cli/Cargo.toml
index 2bbc529f89c..62167fb5007 100644
--- a/lib/cli/Cargo.toml
+++ b/lib/cli/Cargo.toml
@@ -91,7 +91,6 @@ object = "0.30.0"
 wasm-coredump-builder = { version = "0.1.11", optional = true }
 tracing = { version = "0.1" }
 tracing-subscriber = { version = "0.3", features = [ "env-filter", "fmt" ] }
-clap-verbosity-flag = "2"
 async-trait = "0.1.68"
 tokio = { version = "1.28.1", features = ["macros", "rt-multi-thread"] }
 once_cell = "1.17.1"
diff --git a/lib/cli/src/cli.rs b/lib/cli/src/cli.rs
index d8734a17556..8cd828a3f98 100644
--- a/lib/cli/src/cli.rs
+++ b/lib/cli/src/cli.rs
@@ -218,6 +218,8 @@ pub fn wasmer_main() {
 }
 
 fn wasmer_main_inner() -> Result<(), anyhow::Error> {
+    crate::logging::set_up_logging();
+
     // We try to run wasmer with the normal arguments.
     // Eg. `wasmer <SUBCOMMAND>`
     // In case that fails, we fallback trying the Run subcommand directly.
diff --git a/lib/cli/src/commands/run.rs b/lib/cli/src/commands/run.rs
index 85505b18da1..f2dea753a1d 100644
--- a/lib/cli/src/commands/run.rs
+++ b/lib/cli/src/commands/run.rs
@@ -16,7 +16,6 @@ use std::{
 
 use anyhow::{Context, Error};
 use clap::Parser;
-use clap_verbosity_flag::WarnLevel;
 use once_cell::sync::Lazy;
 use sha2::{Digest, Sha256};
 use tempfile::NamedTempFile;
@@ -58,8 +57,6 @@ static WASMER_HOME: Lazy<PathBuf> = Lazy::new(|| {
 /// The unstable `wasmer run` subcommand.
 #[derive(Debug, Parser)]
 pub struct Run {
-    #[clap(flatten)]
-    verbosity: clap_verbosity_flag::Verbosity<WarnLevel>,
     /// The Wasmer home directory.
     #[clap(long = "wasmer-dir", env = "WASMER_DIR", default_value = WASMER_HOME.as_os_str())]
     wasmer_dir: PathBuf,
@@ -92,7 +89,6 @@ impl Run {
     }
 
     fn execute_inner(&self) -> Result<(), Error> {
-        crate::logging::set_up_logging(self.verbosity.log_level_filter());
         let runtime = tokio::runtime::Builder::new_multi_thread()
             .enable_all()
             .build()?;
@@ -360,7 +356,6 @@ impl Run {
         };
         let store = StoreOptions::default();
         Ok(Run {
-            verbosity: clap_verbosity_flag::Verbosity::new(0, 0),
             wasmer_dir: WASMER_HOME.clone(),
             store,
             wasi: Wasi::for_binfmt_interpreter()?,
diff --git a/lib/cli/src/logging.rs b/lib/cli/src/logging.rs
index 54ce76c6275..987c3fa6446 100644
--- a/lib/cli/src/logging.rs
+++ b/lib/cli/src/logging.rs
@@ -1,11 +1,12 @@
 //! Logging functions for the debug feature.
 
 use tracing_subscriber::{
-    filter::Directive, fmt, layer::SubscriberExt, util::SubscriberInitExt, EnvFilter,
+    fmt, layer::SubscriberExt, util::SubscriberInitExt, EnvFilter,
 };
 
-/// Subroutine to instantiate the loggers
-pub fn set_up_logging(level: log::LevelFilter) {
+/// Initialize logging based on the `$RUST_LOG` environment variable. Logs will
+/// be disabled when `$RUST_LOG` isn't set.
+pub fn set_up_logging() {
     let fmt_layer = fmt::layer()
         .with_target(true)
         .with_span_events(fmt::format::FmtSpan::CLOSE)
@@ -15,7 +16,6 @@ pub fn set_up_logging(level: log::LevelFilter) {
         .compact();
 
     let filter_layer = EnvFilter::builder()
-        .with_default_directive(log_directive(level))
         .from_env_lossy();
 
     tracing_subscriber::registry()
@@ -34,15 +34,3 @@ fn should_emit_colors() -> bool {
     isatty::stderr_isatty() && std::env::var_os("NO_COLOR").is_none()
 }
 
-fn log_directive(level: log::LevelFilter) -> Directive {
-    let tracing_level = match level {
-        log::LevelFilter::Off => tracing::level_filters::LevelFilter::OFF,
-        log::LevelFilter::Error => tracing::level_filters::LevelFilter::ERROR,
-        log::LevelFilter::Warn => tracing::level_filters::LevelFilter::WARN,
-        log::LevelFilter::Info => tracing::level_filters::LevelFilter::INFO,
-        log::LevelFilter::Debug => tracing::level_filters::LevelFilter::DEBUG,
-        log::LevelFilter::Trace => tracing::level_filters::LevelFilter::TRACE,
-    };
-
-    tracing_level.into()
-}