opt out for vortex-python _lib

Signed-off-by: blaginin <github@blaginin.me>

Author: blaginin

vortex-python/Cargo.toml

@@ -21,6 +21,13 @@ workspace = true
 [lib]
 crate-type = ["rlib", "cdylib"]
 
+[features]
+default = ["extension-module"]
+# Enable this feature when building the standalone Python extension.
+# Disable it when using vortex-python as a library dependency to avoid
+# duplicate PyInit__lib symbols.
+extension-module = []
+
 [dependencies]
 arrow-array = { workspace = true }
 arrow-data = { workspace = true }

vortex-python/src/lib.rs

@@ -47,6 +47,7 @@ static SESSION: LazyLock<VortexSession> =
     LazyLock::new(|| VortexSession::default().with_handle(RUNTIME.handle()));
 
 /// Vortex is an Apache Arrow-compatible toolkit for working with compressed array data.
+#[cfg(feature = "extension-module")]
 #[pymodule]
 fn _lib(py: Python, m: &Bound<PyModule>) -> PyResult<()> {
     Python::attach(|py| -> PyResult<()> {