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node-api: deprecate napi_module_register based registration

Rodrigo Muino Tomonari requested to merge github/fork/vmoroz/dev/vmoroz/PR/deprecate_napi_module_register into main

Summary

Change NAPI_MODULE and NAPI_MODULE_INIT macros to use symbol-based module registration. Symbol-based registration was added in PR #20161 and used by Node-API modules written in non-C++ languages. It is much simpler and requires no work on module library load.

Details

Currently ABI-safe Node-API modules have two ways to register modules:

  • Create napi_module struct and call napi_module_register on module library (.so or .dll) load.
  • Define napi_register_module_v1 function which is called on-demand to initialize module exports.

Node.JS module binding loads module library and then

  • if it finds registered napi_module struct, then it uses its nm_register_func to initialize module exports,
  • otherwise, it tries to find the napi_register_module_v1 and calls it to initialize module exports.

The first registration method is the original Node-API (NAPI) module registration. The second method (aka symbol-based registration) was added in PR #20161 on Apr 23, 2018, and available in Node.JS from version 10.

It is interesting to see that all Node-API bindings written in other languages (Rust, Go, etc.) they all use the symbol-based registration. Even the C/C++ WASM bindings use the symbol-based registration. It is easier to implement, and it does not need calling code on module library load.

In this PR we align C/C++ Node-API registration with registration in other languages to use the symbol-based registration. The NAPI_MODULE and NAPI_MODULE_INIT macros are changed to define the napi_register_module_v1 function instead of calling napi_module_register. It effectively deprecates the napi_module_register function, but since no changes are made to the Node.JS binding mechanism, all previously compiled modules must continue to work.

The test_null_init is removed because new macros fail to compile if the NULL parameter is given to the NAPI_MODULE macro.

This PR is a "spin off" from the PR #45715 to keep it focused on the new versioning approach.

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