README.md

About

Helper crate for linking to the pre-built libpython from Webassembly Language Runtimes.

Features

build

This feature is intended for usage in build.rs scripts. It will download all needed pre-built static libraries for wasm32-wasi and configure the linker to use them.

To use this feature add this to your Cargo.toml

[build-dependencies]
wlr-libpy = { git = "https://github.com/vmware-labs/webassembly-language-runtimes.git", features = ["build"] }

Then, in the build.rs file of your project you only need to call configure_static_libs().unwrap().emit_link_flags() like this:

fn main() {
    // ...
    use wlr_libpy::bld_cfg::configure_static_libs;
    configure_static_libs().unwrap().emit_link_flags();
    // ...
}

Here is a list of the pre-built wasm32-wasi static libraries:

• wasi-sysroot-20.0.tar.gz provides some POSIX emulations
• libclang_rt.builtins-wasm32-wasi-20.0.tar.gz provides some built-ins which may be required by code built via clang (like the libpython that we publish)
• libpython-3.11.4-wasi-sdk-20.0.tar provides our pre-built version of libpython

py_main

This feature is a helper, if you want to wrap the Python interpreter and call it's Py_Main method. This is useful when you want to add some python modules defined in Rust as builtin modules (e.g. via PyImport_AppendInittab) and then call on the standard Python code. A typical use case would be whenever you want to provide Python bindings for Wasm host functions.

To use this feature add this to your Cargo.toml

[dependencies]
...
wlr-libpy = { git = "https://github.com/vmware-labs/webassembly-language-runtimes.git", features = ["py_main"] }

Then to call on the Py_Main method just do this:

fn main() {
    use wlr_libpy::py_main::py_main;
    py_main(std::env::args().collect());
}