From fe5d6d59e6989dfc4e76586a1f8b142a1305a901 Mon Sep 17 00:00:00 2001
From: Pat Hickey <pat@moreproductive.org>
Date: Tue, 1 Sep 2020 14:34:12 -0700
Subject: [PATCH] wasi example: theres lots of useful tracing messages for
 debugging

---
 Cargo.lock            | 2 ++
 Cargo.toml            | 2 ++
 examples/wasi/main.rs | 5 +++++
 3 files changed, 9 insertions(+)

diff --git a/Cargo.lock b/Cargo.lock
index b2acc2ea90..c79c06601b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2419,6 +2419,8 @@ dependencies = [
  "target-lexicon",
  "tempfile",
  "test-programs",
+ "tracing",
+ "tracing-subscriber",
  "wasi-common",
  "wasmtime",
  "wasmtime-cache",
diff --git a/Cargo.toml b/Cargo.toml
index ba36d92e89..666f918b14 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -51,6 +51,8 @@ tempfile = "3.1.0"
 test-programs = { path = "crates/test-programs" }
 wasmtime-fuzzing = { path = "crates/fuzzing" }
 wasmtime-runtime = { path = "crates/runtime" }
+tracing = "0.1.12"
+tracing-subscriber = "0.2.0"
 
 [build-dependencies]
 anyhow = "1.0.19"
diff --git a/examples/wasi/main.rs b/examples/wasi/main.rs
index 35cb948135..5769069443 100644
--- a/examples/wasi/main.rs
+++ b/examples/wasi/main.rs
@@ -8,6 +8,11 @@ use wasmtime::*;
 use wasmtime_wasi::{Wasi, WasiCtx};
 
 fn main() -> Result<()> {
+    tracing_subscriber::FmtSubscriber::builder()
+        .with_env_filter(tracing_subscriber::EnvFilter::from_default_env())
+        .with_ansi(true)
+        .init();
+
     let store = Store::default();
     let mut linker = Linker::new(&store);