WASI support

.github/workflows/CI.yml

@@ -148,15 +148,18 @@ jobs:
     - name: Run doctests
       run: cargo test --doc --workspace
 
-  test-build-wasm:
-    name: build tests (wasm)
+  test-build-across-targets:
+    name: build tests (${{ matrix.target }})
     needs: check
+    strategy:
+      matrix:
+        target: [wasm32-unknown-unknown, wasm32-wasi]
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4
     - uses: dtolnay/rust-toolchain@stable
       with:
-        target: wasm32-unknown-unknown
+        target: ${{ matrix.target }}
     - name: build all tests
       run: cargo test --no-run
 
@@ -169,7 +172,7 @@ jobs:
       - style
       - cargo-hack
       - check-msrv
-      - test-build-wasm
+      - test-build-across-targets
       - test
     steps:
       - run: exit 0

src/layer.rs

@@ -7,7 +7,7 @@ use opentelemetry::{
 use std::fmt;
 use std::marker;
 use std::thread;
-#[cfg(not(target_arch = "wasm32"))]
+#[cfg(not(all(target_arch = "wasm32", not(target_os = "wasi"))))]
 use std::time::Instant;
 use std::{any::TypeId, borrow::Cow};
 use tracing_core::span::{self, Attributes, Id, Record};
@@ -17,7 +17,7 @@ use tracing_log::NormalizeEvent;
 use tracing_subscriber::layer::Context;
 use tracing_subscriber::registry::LookupSpan;
 use tracing_subscriber::Layer;
-#[cfg(target_arch = "wasm32")]
+#[cfg(all(target_arch = "wasm32", not(target_os = "wasi")))]
 use web_time::Instant;
 
 const SPAN_NAME_FIELD: &str = "otel.name";

src/lib.rs

@@ -154,12 +154,12 @@ pub struct OtelData {
 pub(crate) mod time {
     use std::time::SystemTime;
 
-    #[cfg(not(target_arch = "wasm32"))]
+    #[cfg(not(all(target_arch = "wasm32", not(target_os = "wasi"))))]
     pub(crate) fn now() -> SystemTime {
         SystemTime::now()
     }
 
-    #[cfg(target_arch = "wasm32")]
+    #[cfg(all(target_arch = "wasm32", not(target_os = "wasi")))]
     pub(crate) fn now() -> SystemTime {
         SystemTime::UNIX_EPOCH + std::time::Duration::from_millis(js_sys::Date::now() as u64)
     }