fix: use explicit extension-module features

Cargo.toml

@@ -8,7 +8,7 @@ thiserror = "1.0.57"
 serde = { version = "1.0.145", features = ["derive"] }
 opentelemetry = { version = "0.23.0" }
 opentelemetry_sdk = { version = "0.23.0" }
-pyo3 = { version = "0.20.0", features = ["macros", "extension-module"] }
+pyo3 = { version = "0.20.0", features = ["macros"] }
 pyo3-asyncio = { version = "0.20.0", features = ["tokio-runtime"] }
 pyo3-build-config = "0.20.0"
 rstest = "0.17.0"

crates/opentelemetry/Cargo.toml

@@ -26,4 +26,6 @@ tracing-opentelemetry = { workspace = true }
 tracing-subscriber = { workspace = true }
 
 [features]
+extension-module = ["pyo3/extension-module"]
+default = ["extension-module"]
 

crates/tracing-subscriber/Cargo.toml

@@ -12,13 +12,13 @@ rust-version = "1.67.0"
 
 [dependencies]
 handlebars = { version = "4.4.0", optional = true }
-pyo3 = { workspace = true }
+pyo3 = { workspace = true, optional = true }
 opentelemetry = { workspace = true }
 opentelemetry-otlp = { version = "0.16.0", features = ["grpc-tonic", "trace", "tls-roots"], optional = true }
 opentelemetry-proto = { version = "0.6.0", optional = true, features = ["tonic"] }
 opentelemetry-stdout = { version = "0.4.0", optional = true, features = ["trace"] }
 opentelemetry_sdk = { workspace = true, features = ["rt-tokio", "rt-tokio-current-thread"] }
-pyo3-asyncio = { workspace = true, features = ["tokio-runtime"] }
+pyo3-asyncio = { workspace = true, features = ["tokio-runtime"], optional = true }
 serde = { workspace = true }
 thiserror = { workspace = true }
 tokio = { workspace = true, features = ["rt-multi-thread"] }
@@ -31,6 +31,9 @@ tracing-subscriber = { workspace = true, features = ["env-filter", "fmt", "json"
 layer-otel-otlp = ["dep:opentelemetry-otlp", "dep:opentelemetry-proto", "dep:tonic"]
 layer-otel-otlp-file = ["dep:opentelemetry-stdout"]
 stubs = ["dep:handlebars"]
+pyo3 = ["dep:pyo3", "dep:pyo3-asyncio"]
+extension-module = ["pyo3", "pyo3/extension-module"]
+default = ["extension-module"]
 
 [dev-dependencies]
 rstest = { workspace = true }

crates/tracing-subscriber/src/lib.rs

@@ -62,9 +62,11 @@
 //!
 //! # Features
 //!
+//! * `pyo3` - enables the Python bindings for the tracing subscriber. This feature is enabled by default.
+//! * `extension-module` - enables the Python extension module for the tracing subscriber. This feature is enabled by default.
 //! * `layer-otel-otlp-file` - exports trace data with `opentelemetry-stdout`. See `crate::layers::otel_otlp_file`.
 //! * `layer-otel-otlp` - exports trace data with `opentelemetry-otlp`. See `crate::layers::otel_otlp`.
-//! * `stubs` - supports writing stub files in your Python source code from your Rust build scripts. See `crates::stubs`
+//! * `stubs` - supports writing stub files in your Python source code from your Rust build scripts. See `crates::stubs`. This should only be used in build scripts with default features disabled.
 //!
 //! # Requirements and Limitations
 //!
@@ -110,7 +112,8 @@
 //!
 //! async main():
 //!     async with Tracing():
-//!         # do stuff
+//!      
+//!      # do stuff
 //!         pass
 //!
 //!
@@ -121,22 +124,31 @@
 //! # Related Crates
 //!
 //! * `pyo3-opentelemetry` - propagates `OpenTelemetry` contexts from Python into Rust.
+#[cfg(feature = "pyo3")]
 use pyo3::{types::PyModule, PyResult, Python};
 
+#[cfg(feature = "pyo3")]
 use self::{
     contextmanager::{CurrentThreadTracingConfig, GlobalTracingConfig, TracingContextManagerError},
     export_process::{BatchConfig, SimpleConfig, TracingShutdownError, TracingStartError},
 };
+#[cfg(feature = "pyo3")]
 pub use contextmanager::Tracing;
 
+#[cfg(feature = "pyo3")]
 pub(crate) mod common;
+#[cfg(feature = "pyo3")]
 mod contextmanager;
+#[cfg(feature = "pyo3")]
 mod export_process;
+#[cfg(feature = "pyo3")]
 pub(crate) mod layers;
 #[cfg(feature = "stubs")]
 pub mod stubs;
+#[cfg(feature = "pyo3")]
 pub(crate) mod subscriber;
 
+#[cfg(feature = "pyo3")]
 create_init_submodule! {
     classes: [
         Tracing,
@@ -152,6 +164,7 @@ create_init_submodule! {
     ],
 }
 
+#[cfg(feature = "pyo3")]
 /// Add the tracing submodule to the given module. This will add the submodule to the `sys.modules`
 /// dictionary so that it can be imported from Python.
 ///

examples/pyo3-opentelemetry-lib/Cargo.toml

@@ -31,6 +31,6 @@ tracing-subscriber = { version = "0.3.17", features = ["env-filter"], optional =
 [features]
 
 [build-dependencies]
-pyo3-tracing-subscriber = { path = "../../crates/tracing-subscriber", features = ["layer-otel-otlp-file", "layer-otel-otlp", "stubs"] }
+pyo3-tracing-subscriber = { path = "../../crates/tracing-subscriber", features = ["layer-otel-otlp-file", "layer-otel-otlp", "stubs"], default-features = false }
 pyo3-build-config.workspace = true